Single turbo vs V8 need help
02-21-14, 08:12 PM
#26
Just take the blue pill..
I'll chime in and say I have plans to LSX an Fc. But, I had my FD with rotary and GT35R tuned by Steve Kan and as long as I stay below ~5psi under cruise and light load I easily see ~25mpg highway and ~17mpg city. Last dyno showed roughly 390whp (mustang) @ 15psi. The car is extremely reliable haven't had an issue with it in over two years. With rotaries, it's all in the tune and attention to detail while building it. You CAN have cake and eat it too.
02-22-14, 11:32 AM
#27
As it seems you already made a choice I'm going to post this for posterity. The long of the short is I have an ls1 sitting in my fc, running, but not quite on the road yet and wish I hadn't done the swap, and this is far from my first swap/large project.
If money is a concern for you I highly suggest doing a detailed cost analysis. To do an engine swap that isn't half-assed and is reliable takes a good deal more time and money than most people realize. Miscellaneous nuts, bolts, consumables, etc. will cost hundreds of dollars by the time you're done. Even buying a kit that will have most of what you need (to put only the engine/trans in) will have unforeseen ancillary costs.
Which LSx motor you chose will greatly affect the end cost and reliability. For instance, ls1's aren't as ubiquitous now and the ones you will find are often the worst examples; make sure you do a compression test before handing over money. Want an ls2? Pay more. Want a truck motor? Pay about the same as an ls1 because you need many parts off an ls1 to get it to fit, all the while tacking on another 100lbs or so on top of what an ls1 weighs. Can you live without power steering or a/c? Adapting those systems will add money and keep the weight up.
Which harness will you use? Going to splice the stock harnesses? Better do a damn good job or you'll have electrical gremlins. If you think you'll do it yourself, are you sure? This is often the biggest stumbling point of any swap. Buying a premade harness? More money and they better be reputable or you'll still be chasing electrical gremlins.
But mostly, is your car in good enough shape, mechanically or electrically to even consider a single turbo or v8?
Fully dressed ls1 weighs ~500 lbs. Fully dressed 13bt ~400lbs. Fully dressed 13b-rew ~420lbs. Stock 5 speed rx7 trans is a good bit lighter than a t56. Stock rear in an rx7 is lighter than an 8.8 IRS. An ls1 WILL place a portion of its engine in front of the front drive line along with all of its accessories. An ls1 is taller and wider and its shape moves its weight higher and then further from the center line. If you don't think this affects performance then put a 50lb battery next to each shock tower and take your car for a spin.
Those fully dressed weights are with the stock cast iron manifolds, arguably one of the worst features of the stock rotary engine due to the thermal properties of iron. Switching to a single turbo setup will not only lighten the car further but also improve its handling and reliability.
If money is a concern for you I highly suggest doing a detailed cost analysis. To do an engine swap that isn't half-assed and is reliable takes a good deal more time and money than most people realize. Miscellaneous nuts, bolts, consumables, etc. will cost hundreds of dollars by the time you're done. Even buying a kit that will have most of what you need (to put only the engine/trans in) will have unforeseen ancillary costs.
Which LSx motor you chose will greatly affect the end cost and reliability. For instance, ls1's aren't as ubiquitous now and the ones you will find are often the worst examples; make sure you do a compression test before handing over money. Want an ls2? Pay more. Want a truck motor? Pay about the same as an ls1 because you need many parts off an ls1 to get it to fit, all the while tacking on another 100lbs or so on top of what an ls1 weighs. Can you live without power steering or a/c? Adapting those systems will add money and keep the weight up.
Which harness will you use? Going to splice the stock harnesses? Better do a damn good job or you'll have electrical gremlins. If you think you'll do it yourself, are you sure? This is often the biggest stumbling point of any swap. Buying a premade harness? More money and they better be reputable or you'll still be chasing electrical gremlins.
But mostly, is your car in good enough shape, mechanically or electrically to even consider a single turbo or v8?
Those fully dressed weights are with the stock cast iron manifolds, arguably one of the worst features of the stock rotary engine due to the thermal properties of iron. Switching to a single turbo setup will not only lighten the car further but also improve its handling and reliability.
02-22-14, 11:16 PM
#28
Full Member
Thread Starter
Join Date: Nov 2013
Location: United States
Posts: 124
Likes: 0
Received 0 Likes
on
0 Posts
As it seems you already made a choice I'm going to post this for posterity. The long of the short is I have an ls1 sitting in my fc, running, but not quite on the road yet and wish I hadn't done the swap, and this is far from my first swap/large project.
If money is a concern for you I highly suggest doing a detailed cost analysis. To do an engine swap that isn't half-assed and is reliable takes a good deal more time and money than most people realize. Miscellaneous nuts, bolts, consumables, etc. will cost hundreds of dollars by the time you're done. Even buying a kit that will have most of what you need (to put only the engine/trans in) will have unforeseen ancillary costs.
Which LSx motor you chose will greatly affect the end cost and reliability. For instance, ls1's aren't as ubiquitous now and the ones you will find are often the worst examples; make sure you do a compression test before handing over money. Want an ls2? Pay more. Want a truck motor? Pay about the same as an ls1 because you need many parts off an ls1 to get it to fit, all the while tacking on another 100lbs or so on top of what an ls1 weighs. Can you live without power steering or a/c? Adapting those systems will add money and keep the weight up.
Which harness will you use? Going to splice the stock harnesses? Better do a damn good job or you'll have electrical gremlins. If you think you'll do it yourself, are you sure? This is often the biggest stumbling point of any swap. Buying a premade harness? More money and they better be reputable or you'll still be chasing electrical gremlins.
But mostly, is your car in good enough shape, mechanically or electrically to even consider a single turbo or v8?
Fully dressed ls1 weighs ~500 lbs. Fully dressed 13bt ~400lbs. Fully dressed 13b-rew ~420lbs. Stock 5 speed rx7 trans is a good bit lighter than a t56. Stock rear in an rx7 is lighter than an 8.8 IRS. An ls1 WILL place a portion of its engine in front of the front drive line along with all of its accessories. An ls1 is taller and wider and its shape moves its weight higher and then further from the center line. If you don't think this affects performance then put a 50lb battery next to each shock tower and take your car for a spin.
Those fully dressed weights are with the stock cast iron manifolds, arguably one of the worst features of the stock rotary engine due to the thermal properties of iron. Switching to a single turbo setup will not only lighten the car further but also improve its handling and reliability.
If money is a concern for you I highly suggest doing a detailed cost analysis. To do an engine swap that isn't half-assed and is reliable takes a good deal more time and money than most people realize. Miscellaneous nuts, bolts, consumables, etc. will cost hundreds of dollars by the time you're done. Even buying a kit that will have most of what you need (to put only the engine/trans in) will have unforeseen ancillary costs.
Which LSx motor you chose will greatly affect the end cost and reliability. For instance, ls1's aren't as ubiquitous now and the ones you will find are often the worst examples; make sure you do a compression test before handing over money. Want an ls2? Pay more. Want a truck motor? Pay about the same as an ls1 because you need many parts off an ls1 to get it to fit, all the while tacking on another 100lbs or so on top of what an ls1 weighs. Can you live without power steering or a/c? Adapting those systems will add money and keep the weight up.
Which harness will you use? Going to splice the stock harnesses? Better do a damn good job or you'll have electrical gremlins. If you think you'll do it yourself, are you sure? This is often the biggest stumbling point of any swap. Buying a premade harness? More money and they better be reputable or you'll still be chasing electrical gremlins.
But mostly, is your car in good enough shape, mechanically or electrically to even consider a single turbo or v8?
Fully dressed ls1 weighs ~500 lbs. Fully dressed 13bt ~400lbs. Fully dressed 13b-rew ~420lbs. Stock 5 speed rx7 trans is a good bit lighter than a t56. Stock rear in an rx7 is lighter than an 8.8 IRS. An ls1 WILL place a portion of its engine in front of the front drive line along with all of its accessories. An ls1 is taller and wider and its shape moves its weight higher and then further from the center line. If you don't think this affects performance then put a 50lb battery next to each shock tower and take your car for a spin.
Those fully dressed weights are with the stock cast iron manifolds, arguably one of the worst features of the stock rotary engine due to the thermal properties of iron. Switching to a single turbo setup will not only lighten the car further but also improve its handling and reliability.
02-24-14, 07:36 AM
#29
FWIW, my LS1 car gets just about 30 mpg highway, 18 mpg city, and that's on E85 with 750+ RWHP. It's really all about tuning as far as that goes. A big nasty heads/cam car will get worse fuel mileage, but not terrifically so. A 450 RWHP heads/cam car should be able to pull 25+ mpg highway without issue.
As far as what is best, as said, it's really all about preference. I will say if you're aren't ready to do a lot of work, which requires patience, money and skill, leave the rotary in, it's way more fun with a rotary than it is on jack stands.
As far as what is best, as said, it's really all about preference. I will say if you're aren't ready to do a lot of work, which requires patience, money and skill, leave the rotary in, it's way more fun with a rotary than it is on jack stands.
03-05-14, 10:17 PM
#30
Senior Member
iTrader: (49)
Join Date: May 2011
Location: Bay Area -> California
Posts: 338
Likes: 0
Received 0 Likes
on
0 Posts
I'll chime in here with a low mileage chassis...
I had 28k on my FD before I pulled my engine.... and NOT because of necessity.
I simply wanted more power and reliability.
I have all the creature comfort minus cruise control, but neither does an R1 model.
My car is a '95 PEP with A/C that weighed in on a corner balance at 2904 with full spare, tools and a full tank (with 20 miles of highway driving).
People will argue what's heavier and what's lighter but let's be honest, most of us WON'T be able to tell which is heavier by driving the car. Even at a 100lb difference, lighter or heavier, I would go with an LS swap. The main selling point would have to be the aftermarket support. Parts are easy to source and are typically not too expensive. Don't forget, power is pretty easy to make.
I had 28k on my FD before I pulled my engine.... and NOT because of necessity.
I simply wanted more power and reliability.
I have all the creature comfort minus cruise control, but neither does an R1 model.
My car is a '95 PEP with A/C that weighed in on a corner balance at 2904 with full spare, tools and a full tank (with 20 miles of highway driving).
People will argue what's heavier and what's lighter but let's be honest, most of us WON'T be able to tell which is heavier by driving the car. Even at a 100lb difference, lighter or heavier, I would go with an LS swap. The main selling point would have to be the aftermarket support. Parts are easy to source and are typically not too expensive. Don't forget, power is pretty easy to make.
03-20-14, 09:16 PM
#31
Triangles and Cats
I hate to see rotaries ripped out of RX7s, so due to my bias I'd say keep that bay free of pistons. But that's just my opinion. I'm not gonna go so far as to say that V8 swaps are for lazy people, because that's ignorant, but in my opinion if you bought an RX7 in the first place you should respect the beautiful piece of engineering marvel it was built with, and build on that if you want more power.
Just my two cents.
Just my two cents.
03-21-14, 11:28 AM
#32
How is that ignorant? Many people who do v8 swaps often quote a desire for more reliability. Rotaries are more unreliable than piston engines when neglected and abused (i.e. they're too lazy to do reliability mods and basic maintenance). And baring examples like digitalsolo who make fairly large amounts of power most who desire the swap will stay within power levels close to those attainable by a dual-rotor. This isn't to say there aren't many reasons a person might do such a swap, but they are typically personal, and power/reliability are used to make the list longer and sound better.
Speak for yourself. I can easily tell the difference in power/handling with a full tank vs half tank vs empty tank. And there is no argument about which is lighter/heavier. All other things being equal, a rotary is lighter. End of discussion.
People will argue what's heavier and what's lighter but let's be honest, most of us WON'T be able to tell which is heavier by driving the car. Even at a 100lb difference, lighter or heavier, I would go with an LS swap. The main selling point would have to be the aftermarket support. Parts are easy to source and are typically not too expensive. Don't forget, power is pretty easy to make.
05-01-14, 02:20 PM
#35
There are valid arguments to doing both. It all boils down to what puts a smile on your face, how deep your wallet is, how much spare time you have and what resources you have around you to utilize. If you're on the original engine with original seals, they're old and tired, so don't expect to last forever if you push the car hard. But there are many apex seals today that can put up with a LOT of abuse even if the tune is half a**ed. All else being equal a properly built rotary will probably never last as long as a built LSX since it is working 30% harder to make the same power but if it lasts you 5+ years of excitement, rebuilding them is quite simple and can be very cheap as long as there's no catastrophic damage. I'm slightly biased to a rotary in an Rotary Xperiment car but I've been in both and can say that if I closed my eyes in the LS FD I was in, I would have thought I was in a corvette. Great torque, and power, but the balance of the car was off in comparison to the smooth power delievery of a rotary. Either way, you have a great chassis that will perform great with practically any powertrain.
EDIT:
Turbo rotaries in comparison to LS motors don't last a long time, they really don't. If you get 120k miles out of an engine that's modified you're doing great, but this is something a rotary owner has to accept...it is a VERY small, compact engine that is forced to make power with engines several times its size. You have to be a little forgiving when you think about how much you ask a 13B to do. It has taken me 6 years to drive 100k miles on my DD (Saturn) and I drive out of state almost every weekend and travel for work. My FC has gone 30k miles since 2006 and I have beat that car very hard and it never gives up, so if you put that into perspective rotaries do have a long lifetime IF it's not your DD...which I highly would not recommend. But for a car that you crank up on a nice day and enjoy the smooth power delivery of the engine and whistle of the turbos, I've never experienced a better car.
EDIT:
Turbo rotaries in comparison to LS motors don't last a long time, they really don't. If you get 120k miles out of an engine that's modified you're doing great, but this is something a rotary owner has to accept...it is a VERY small, compact engine that is forced to make power with engines several times its size. You have to be a little forgiving when you think about how much you ask a 13B to do. It has taken me 6 years to drive 100k miles on my DD (Saturn) and I drive out of state almost every weekend and travel for work. My FC has gone 30k miles since 2006 and I have beat that car very hard and it never gives up, so if you put that into perspective rotaries do have a long lifetime IF it's not your DD...which I highly would not recommend. But for a car that you crank up on a nice day and enjoy the smooth power delivery of the engine and whistle of the turbos, I've never experienced a better car.
05-07-14, 03:50 PM
#36
If you are even considering an LS swap, then I would do it now. Here is why,... the swap really isn't cheap but rotary power isn't either. When I first went single turbo, I looked at a LS swap in comparison. I considered doing it then, but I really talked myself out of it because I never had a high HP rotary and I told myself that I had to at least try it. Being a rotary owner for over 15 years, it made sense. I spent $9k going single turbo. I did it the right way and bought new quality parts. I could have done it for a little less, but it was a nice GT35R with Vmount, fuel, and all the goodies. I hypothetically added up a LS1 swap and it had me sitting at around $11k. Again, all quality parts. My 35R setup yielded 386whp, and the LS1 with the considered mods would have done the same. I upgraded my setup a few times after that, but always spending more money to make more power. Each time I considered the swap, I thought it was silly since I already had gone that direction. When I finally decided to do a LS, I had a blown engine and pile of parts. Oh the money I would have saved....
You now have a good engine and drivetrain that is worth good money. In completely stock form with low mileage, you have a leg up for a few reasons. You haven't done a bunch of work to the car, and you have a nice pot of cash sitting in your bay to start funding the swap.
As others have said, it really is personal preference. I prefer a turbo rotary, but we all know it costs more to squeeze big power from a small engine. It's simple physics and there is no denying it. If you think you will start going down that rabbit hole, I would consider the swap now. Put a nice LS3 or stroker motor in there and enjoy.
For me, it came down to power and cost. I love the rotary, and always will. But no matter how much voodoo you pump into it, it is still a 1.3 liter. Mid 300's with E85/AI and the rotary will do very well. But the point came that I had mid 400's and still wanted more....
My power addiction surpassed my rotary addiction. Life happened and I just got tired of working on the car. I looked at my future and saw a fresh engine every few years, and that was if nothing else inadvertently failed to cause engine failure. Unfortunately, that is another downfall to the little Doritto. It seams that everything causes catastrophic failure, and it spits seals at your nice expensive turbo on the way. In the mid 500whp power range, things of reliability go out the window with the rotary and it's factory drivetrain. Of course, NOTHING against the engine or the design of the drivetrain, it just wasn't built to handle that kind of power. I can build a forged LS engine, make 600hp in NA form, 100k reliable miles, 25mpg, and keep smiling. Use a Tremec T56 Magnum rated for 700ftlbs, and a Cobra IRS 8.8 rear. A bulletproof drivetrain built to handle whatever I could throw at it. And that is what I planned to do....
Ultimately, I probably should have bought a Vette. But after all the blood and sweat I put into my car I couldn't let it go. I just had it painted, and FINALLY the exterior was exactly the way I wanted it. Thus, my reason to swap a LS7.
And of course, there lies another option; to pass on your car to an enthusiast, and purchase a good example of an already swapped car.
You now have a good engine and drivetrain that is worth good money. In completely stock form with low mileage, you have a leg up for a few reasons. You haven't done a bunch of work to the car, and you have a nice pot of cash sitting in your bay to start funding the swap.
As others have said, it really is personal preference. I prefer a turbo rotary, but we all know it costs more to squeeze big power from a small engine. It's simple physics and there is no denying it. If you think you will start going down that rabbit hole, I would consider the swap now. Put a nice LS3 or stroker motor in there and enjoy.
For me, it came down to power and cost. I love the rotary, and always will. But no matter how much voodoo you pump into it, it is still a 1.3 liter. Mid 300's with E85/AI and the rotary will do very well. But the point came that I had mid 400's and still wanted more....
My power addiction surpassed my rotary addiction. Life happened and I just got tired of working on the car. I looked at my future and saw a fresh engine every few years, and that was if nothing else inadvertently failed to cause engine failure. Unfortunately, that is another downfall to the little Doritto. It seams that everything causes catastrophic failure, and it spits seals at your nice expensive turbo on the way. In the mid 500whp power range, things of reliability go out the window with the rotary and it's factory drivetrain. Of course, NOTHING against the engine or the design of the drivetrain, it just wasn't built to handle that kind of power. I can build a forged LS engine, make 600hp in NA form, 100k reliable miles, 25mpg, and keep smiling. Use a Tremec T56 Magnum rated for 700ftlbs, and a Cobra IRS 8.8 rear. A bulletproof drivetrain built to handle whatever I could throw at it. And that is what I planned to do....
Ultimately, I probably should have bought a Vette. But after all the blood and sweat I put into my car I couldn't let it go. I just had it painted, and FINALLY the exterior was exactly the way I wanted it. Thus, my reason to swap a LS7.
And of course, there lies another option; to pass on your car to an enthusiast, and purchase a good example of an already swapped car.
05-07-14, 05:32 PM
#37
All out Track Freak!
iTrader: (263)
Join Date: Jul 2001
Location: Charlottesville VA 22901
Posts: 10,672
Received 416 Likes
on
252 Posts
If you are even considering an LS swap, then I would do it now. Here is why,... the swap really isn't cheap but rotary power isn't either. When I first went single turbo, I looked at a LS swap in comparison. I considered doing it then, but I really talked myself out of it because I never had a high HP rotary and I told myself that I had to at least try it. Being a rotary owner for over 15 years, it made sense. I spent $9k going single turbo. I did it the right way and bought new quality parts. I could have done it for a little less, but it was a nice GT35R with Vmount, fuel, and all the goodies. I hypothetically added up a LS1 swap and it had me sitting at around $11k. Again, all quality parts. My 35R setup yielded 386whp, and the LS1 with the considered mods would have done the same. I upgraded my setup a few times after that, but always spending more money to make more power. Each time I considered the swap, I thought it was silly since I already had gone that direction. When I finally decided to do a LS, I had a blown engine and pile of parts. Oh the money I would have saved....
You now have a good engine and drivetrain that is worth good money. In completely stock form with low mileage, you have a leg up for a few reasons. You haven't done a bunch of work to the car, and you have a nice pot of cash sitting in your bay to start funding the swap.
As others have said, it really is personal preference. I prefer a turbo rotary, but we all know it costs more to squeeze big power from a small engine. It's simple physics and there is no denying it. If you think you will start going down that rabbit hole, I would consider the swap now. Put a nice LS3 or stroker motor in there and enjoy.
For me, it came down to power and cost. I love the rotary, and always will. But no matter how much voodoo you pump into it, it is still a 1.3 liter. Mid 300's with E85/AI and the rotary will do very well. But the point came that I had mid 400's and still wanted more....
My power addiction surpassed my rotary addiction. Life happened and I just got tired of working on the car. I looked at my future and saw a fresh engine every few years, and that was if nothing else inadvertently failed to cause engine failure. Unfortunately, that is another downfall to the little Doritto. It seams that everything causes catastrophic failure, and it spits seals at your nice expensive turbo on the way. In the mid 500whp power range, things of reliability go out the window with the rotary and it's factory drivetrain. Of course, NOTHING against the engine or the design of the drivetrain, it just wasn't built to handle that kind of power. I can build a forged LS engine, make 600hp in NA form, 100k reliable miles, 25mpg, and keep smiling. Use a Tremec T56 Magnum rated for 700ftlbs, and a Cobra IRS 8.8 rear. A bulletproof drivetrain built to handle whatever I could throw at it. And that is what I planned to do....
Ultimately, I probably should have bought a Vette. But after all the blood and sweat I put into my car I couldn't let it go. I just had it painted, and FINALLY the exterior was exactly the way I wanted it. Thus, my reason to swap a LS7.
And of course, there lies another option; to pass on your car to an enthusiast, and purchase a good example of an already swapped car.
You now have a good engine and drivetrain that is worth good money. In completely stock form with low mileage, you have a leg up for a few reasons. You haven't done a bunch of work to the car, and you have a nice pot of cash sitting in your bay to start funding the swap.
As others have said, it really is personal preference. I prefer a turbo rotary, but we all know it costs more to squeeze big power from a small engine. It's simple physics and there is no denying it. If you think you will start going down that rabbit hole, I would consider the swap now. Put a nice LS3 or stroker motor in there and enjoy.
For me, it came down to power and cost. I love the rotary, and always will. But no matter how much voodoo you pump into it, it is still a 1.3 liter. Mid 300's with E85/AI and the rotary will do very well. But the point came that I had mid 400's and still wanted more....
My power addiction surpassed my rotary addiction. Life happened and I just got tired of working on the car. I looked at my future and saw a fresh engine every few years, and that was if nothing else inadvertently failed to cause engine failure. Unfortunately, that is another downfall to the little Doritto. It seams that everything causes catastrophic failure, and it spits seals at your nice expensive turbo on the way. In the mid 500whp power range, things of reliability go out the window with the rotary and it's factory drivetrain. Of course, NOTHING against the engine or the design of the drivetrain, it just wasn't built to handle that kind of power. I can build a forged LS engine, make 600hp in NA form, 100k reliable miles, 25mpg, and keep smiling. Use a Tremec T56 Magnum rated for 700ftlbs, and a Cobra IRS 8.8 rear. A bulletproof drivetrain built to handle whatever I could throw at it. And that is what I planned to do....
Ultimately, I probably should have bought a Vette. But after all the blood and sweat I put into my car I couldn't let it go. I just had it painted, and FINALLY the exterior was exactly the way I wanted it. Thus, my reason to swap a LS7.
And of course, there lies another option; to pass on your car to an enthusiast, and purchase a good example of an already swapped car.
If you want big power and you just like the look and handling of the FD go V8
If you just want big economical power go VETTE and you'll have a much better performing car to boot.
If you really want to have fun and fall in love with the greatest sports car ever built get to know the lady just as she is which will be well worth your time and will also provide endless smiles for many many miles
add a catback (notice about 10 more HP and love the new sound of back fires etc..)
add a nice intake (notice another 10 HP) and listen to those magical twins
add some cool coilovers and learn how controllable the car is as you slide it around
add some sways and have even more fun
add a PFC smic bigger inj etc... and get another 50 HP
blah blah
The engine and the way it loves to be modded and tinkered with is a BIG part of this car and the relationship you and it will have together. If you pass that up you are missing one of this cars greatest gifts.
05-07-14, 06:41 PM
#38
Having owned both and in many various:
Bolt-ons(cai, cat delete, PFC) @13psi so around 340hp, I got 16 at best highway average cruising speed 80-90.
LS3 + ported heads and a turbo cam but n/a (450whp) I got 22 mpg at 95mph(stock rear t56).
Both full interior cars.
Bolt-ons(cai, cat delete, PFC) @13psi so around 340hp, I got 16 at best highway average cruising speed 80-90.
LS3 + ported heads and a turbo cam but n/a (450whp) I got 22 mpg at 95mph(stock rear t56).
Both full interior cars.
05-07-14, 08:14 PM
#39
All out Track Freak!
iTrader: (263)
Join Date: Jul 2001
Location: Charlottesville VA 22901
Posts: 10,672
Received 416 Likes
on
252 Posts
I won't be at all surprised if I'm driving an LSX FD at some point because it just makes soooo much damn sense which only goes to show how much love I have for the rotary LOL.
05-08-14, 05:21 AM
#40
.Bottom line is this. If you have the BIG cheap power bug, can't beat an LS. But I'd recommend keeping your rotary in and just buying a piston car that's already know to make good power. I just sold an e46 m3, but there are kits out there now that are making 660+ rwhp at just 11 psi and over 1000+ rwhp at 25 psi, a 2 rotor will NEVER do that reliably, so you better believe when I get that bug for more power I'm not going to drop an s54 engine in my FD, I'm going to buy a beat up e46 m3 chassis and turbo that beast.
05-08-14, 08:07 AM
#41
Senior Member
iTrader: (6)
Join Date: Mar 2004
Location: Columbia, SC
Posts: 523
Likes: 0
Received 0 Likes
on
0 Posts
Really? I haven't calculated my FD but my FC that I tuned myself would get well over 20+ mpg on the highway. Tune the AFR's to be in the 16's while cruising and worked like a charm. Also had a friend of ours driving to the dragon that had a similar tune in his FD. He drove from Charlotte to the Dragon, drove around for the weekend and didn't fill up until we left on Sunday, I on the other hand filled up 2 times and we cruised together everywhere we went, so it's really all in the tune .
Bottom line is this. If you have the BIG cheap power bug, can't beat an LS. But I'd recommend keeping your rotary in and just buying a piston car that's already know to make good power. I just sold an e46 m3, but there are kits out there now that are making 660+ rwhp at just 11 psi and over 1000+ rwhp at 25 psi, a 2 rotor will NEVER do that reliably, so you better believe when I get that bug for more power I'm not going to drop an s54 engine in my FD, I'm going to buy a beat up e46 m3 chassis and turbo that beast.
.Bottom line is this. If you have the BIG cheap power bug, can't beat an LS. But I'd recommend keeping your rotary in and just buying a piston car that's already know to make good power. I just sold an e46 m3, but there are kits out there now that are making 660+ rwhp at just 11 psi and over 1000+ rwhp at 25 psi, a 2 rotor will NEVER do that reliably, so you better believe when I get that bug for more power I'm not going to drop an s54 engine in my FD, I'm going to buy a beat up e46 m3 chassis and turbo that beast.
05-08-14, 09:52 AM
#42
Really? I haven't calculated my FD but my FC that I tuned myself would get well over 20+ mpg on the highway. Tune the AFR's to be in the 16's while cruising and worked like a charm. Also had a friend of ours driving to the dragon that had a similar tune in his FD. He drove from Charlotte to the Dragon, drove around for the weekend and didn't fill up until we left on Sunday, I on the other hand filled up 2 times and we cruised together everywhere we went, so it's really all in the tune .
Bottom line is this. If you have the BIG cheap power bug, can't beat an LS. But I'd recommend keeping your rotary in and just buying a piston car that's already know to make good power. I just sold an e46 m3, but there are kits out there now that are making 660+ rwhp at just 11 psi and over 1000+ rwhp at 25 psi, a 2 rotor will NEVER do that reliably, so you better believe when I get that bug for more power I'm not going to drop an s54 engine in my FD, I'm going to buy a beat up e46 m3 chassis and turbo that beast.
.Bottom line is this. If you have the BIG cheap power bug, can't beat an LS. But I'd recommend keeping your rotary in and just buying a piston car that's already know to make good power. I just sold an e46 m3, but there are kits out there now that are making 660+ rwhp at just 11 psi and over 1000+ rwhp at 25 psi, a 2 rotor will NEVER do that reliably, so you better believe when I get that bug for more power I'm not going to drop an s54 engine in my FD, I'm going to buy a beat up e46 m3 chassis and turbo that beast.
I never drive my fast cars slow. The rotary dealing with constant decel/recel got terrible mileage but the same chassis with a ls going an average higher speed got better mileage. I know people getting over 26 on e85 on ls turbo car cruising, but thats cruising at the speed limit there is always a story of someone getting XYZ. I can tell you what I got from running the same path, same chassis, same weight, same driver, removes a lot of variables. I have no problem in making a rotary go fast, just the consumables at the power levels we are going to be competing at soon we would have to be running a 20b and a turbo ls is a fraction of that price.
05-08-14, 02:55 PM
#43
Just take the blue pill..
To the OP Maybe this can sway your decision to go to the dark side lol:
https://www.rx7club.com/non-rotary-a...s-etc-1062257/
https://www.rx7club.com/non-rotary-a...s-etc-1062257/
05-08-14, 03:15 PM
#44
Full Member
Join Date: Feb 2013
Location: Iowa
Posts: 134
Likes: 0
Received 0 Likes
on
0 Posts
To the OP Maybe this can sway your decision to go to the dark side lol:
https://www.rx7club.com/non-rotary-a...s-etc-1062257/
https://www.rx7club.com/non-rotary-a...s-etc-1062257/
?
05-13-14, 11:28 AM
#46
Unmatched Power and Fury
If you are even considering an LS swap, then I would do it now. Here is why,... the swap really isn't cheap but rotary power isn't either. When I first went single turbo, I looked at a LS swap in comparison. I considered doing it then, but I really talked myself out of it because I never had a high HP rotary and I told myself that I had to at least try it. Being a rotary owner for over 15 years, it made sense. I spent $9k going single turbo. I did it the right way and bought new quality parts. I could have done it for a little less, but it was a nice GT35R with Vmount, fuel, and all the goodies. I hypothetically added up a LS1 swap and it had me sitting at around $11k. Again, all quality parts. My 35R setup yielded 386whp, and the LS1 with the considered mods would have done the same. I upgraded my setup a few times after that, but always spending more money to make more power. Each time I considered the swap, I thought it was silly since I already had gone that direction. When I finally decided to do a LS, I had a blown engine and pile of parts. Oh the money I would have saved....
You now have a good engine and drivetrain that is worth good money. In completely stock form with low mileage, you have a leg up for a few reasons. You haven't done a bunch of work to the car, and you have a nice pot of cash sitting in your bay to start funding the swap.
As others have said, it really is personal preference. I prefer a turbo rotary, but we all know it costs more to squeeze big power from a small engine. It's simple physics and there is no denying it. If you think you will start going down that rabbit hole, I would consider the swap now. Put a nice LS3 or stroker motor in there and enjoy.
For me, it came down to power and cost. I love the rotary, and always will. But no matter how much voodoo you pump into it, it is still a 1.3 liter. Mid 300's with E85/AI and the rotary will do very well. But the point came that I had mid 400's and still wanted more....
My power addiction surpassed my rotary addiction. Life happened and I just got tired of working on the car. I looked at my future and saw a fresh engine every few years, and that was if nothing else inadvertently failed to cause engine failure. Unfortunately, that is another downfall to the little Doritto. It seams that everything causes catastrophic failure, and it spits seals at your nice expensive turbo on the way. In the mid 500whp power range, things of reliability go out the window with the rotary and it's factory drivetrain. Of course, NOTHING against the engine or the design of the drivetrain, it just wasn't built to handle that kind of power. I can build a forged LS engine, make 600hp in NA form, 100k reliable miles, 25mpg, and keep smiling. Use a Tremec T56 Magnum rated for 700ftlbs, and a Cobra IRS 8.8 rear. A bulletproof drivetrain built to handle whatever I could throw at it. And that is what I planned to do....
Ultimately, I probably should have bought a Vette. But after all the blood and sweat I put into my car I couldn't let it go. I just had it painted, and FINALLY the exterior was exactly the way I wanted it. Thus, my reason to swap a LS7.
And of course, there lies another option; to pass on your car to an enthusiast, and purchase a good example of an already swapped car.
You now have a good engine and drivetrain that is worth good money. In completely stock form with low mileage, you have a leg up for a few reasons. You haven't done a bunch of work to the car, and you have a nice pot of cash sitting in your bay to start funding the swap.
As others have said, it really is personal preference. I prefer a turbo rotary, but we all know it costs more to squeeze big power from a small engine. It's simple physics and there is no denying it. If you think you will start going down that rabbit hole, I would consider the swap now. Put a nice LS3 or stroker motor in there and enjoy.
For me, it came down to power and cost. I love the rotary, and always will. But no matter how much voodoo you pump into it, it is still a 1.3 liter. Mid 300's with E85/AI and the rotary will do very well. But the point came that I had mid 400's and still wanted more....
My power addiction surpassed my rotary addiction. Life happened and I just got tired of working on the car. I looked at my future and saw a fresh engine every few years, and that was if nothing else inadvertently failed to cause engine failure. Unfortunately, that is another downfall to the little Doritto. It seams that everything causes catastrophic failure, and it spits seals at your nice expensive turbo on the way. In the mid 500whp power range, things of reliability go out the window with the rotary and it's factory drivetrain. Of course, NOTHING against the engine or the design of the drivetrain, it just wasn't built to handle that kind of power. I can build a forged LS engine, make 600hp in NA form, 100k reliable miles, 25mpg, and keep smiling. Use a Tremec T56 Magnum rated for 700ftlbs, and a Cobra IRS 8.8 rear. A bulletproof drivetrain built to handle whatever I could throw at it. And that is what I planned to do....
Ultimately, I probably should have bought a Vette. But after all the blood and sweat I put into my car I couldn't let it go. I just had it painted, and FINALLY the exterior was exactly the way I wanted it. Thus, my reason to swap a LS7.
And of course, there lies another option; to pass on your car to an enthusiast, and purchase a good example of an already swapped car.
06-18-14, 08:20 PM
#48
Registered User
A strung out rotary comes with a great many failure critical systems despite having few moving parts. Any problems with cooling (water pump, radiator, hoses etc), fuel (pump, filter, injectors, even just a bad tank of gas), air management (blowoff/wastegate, vacuum leaks), and the engine might be done. Rotaries can be awesome, but damn they are unforgiving. I personally found the rotary less fun to drive since I found never trusted it. We all understand that detonation will spit out apex seals, but I've never seen a good explanation for why coolant seals let go.
Then there's what you can "upgrade" to. IMHO, a single turbo rotary making good power (lets say 450+ rwhp) typically has a terrible torque curve which is pretty non-existent below 3500 rpm. The big single often leaves you driving on e85 or race fuel which is a PITA for many reasons. There's little to no margin in the tune if you want to make power, certainly no enough to tolerance any given component issues as mentioned above. Then, when the power comes in, it hits hard in a big rush, so feathering throttle is challenging. They're simply harder to drive fast. Can you? Absolutely yes. Is it easy? No.
A v8 on the other hand is all about instant gratification. The power is always there. It'll make more torque by 2500 rpm than most rotaries do at redline. Any heads cam setup winds out nicely. Literally my favorite comment from a rotary buddy after I took him for a ride was simply "you've ruined me". All the preconceived notions just fall away after you get a ride in one. It doesn't happen for everyone, some folks just like what they like, but if you're looking to make an objective evaluation of things you should find someone local and get a ride.
The simple fact is that when I did the swap, I quadrupled the displacement, I tripled my horsepower, and my gas mileage went up. I don't know how that doesn't defy physics but there it is.
My advice is that if you have a good running car, NOW is the best time to swap it, when all the goods you're about to take out are still worth top dollar to the purist who just blew up his stuff. Financially speaking and in terms of time committed to the build, the worst scenario you can have happen is that you do go single, then you blow it up, then sell your setup for pennies, and you THEN finally swap it.
If they made a corvette in 9/10ths scale I might be driving one. Until that happens a v8 rx7 is the next best thing.
Good luck!
Then there's what you can "upgrade" to. IMHO, a single turbo rotary making good power (lets say 450+ rwhp) typically has a terrible torque curve which is pretty non-existent below 3500 rpm. The big single often leaves you driving on e85 or race fuel which is a PITA for many reasons. There's little to no margin in the tune if you want to make power, certainly no enough to tolerance any given component issues as mentioned above. Then, when the power comes in, it hits hard in a big rush, so feathering throttle is challenging. They're simply harder to drive fast. Can you? Absolutely yes. Is it easy? No.
A v8 on the other hand is all about instant gratification. The power is always there. It'll make more torque by 2500 rpm than most rotaries do at redline. Any heads cam setup winds out nicely. Literally my favorite comment from a rotary buddy after I took him for a ride was simply "you've ruined me". All the preconceived notions just fall away after you get a ride in one. It doesn't happen for everyone, some folks just like what they like, but if you're looking to make an objective evaluation of things you should find someone local and get a ride.
The simple fact is that when I did the swap, I quadrupled the displacement, I tripled my horsepower, and my gas mileage went up. I don't know how that doesn't defy physics but there it is.
My advice is that if you have a good running car, NOW is the best time to swap it, when all the goods you're about to take out are still worth top dollar to the purist who just blew up his stuff. Financially speaking and in terms of time committed to the build, the worst scenario you can have happen is that you do go single, then you blow it up, then sell your setup for pennies, and you THEN finally swap it.
If they made a corvette in 9/10ths scale I might be driving one. Until that happens a v8 rx7 is the next best thing.
Good luck!
06-19-14, 12:15 PM
#50
Rotary Enthusiast
iTrader: (19)
Join Date: Apr 2002
Location: Colorado Springs, CO
Posts: 1,169
Likes: 0
Received 11 Likes
on
10 Posts
I think modern day turbo's are pretty good. The EFR series turbo's are great turbo's and can make good power at low boost.
I would run the rotary as it comes with the car and everything is designed for it. It's true that maintenance and upkeep are a huge deal with the rotary, running 2 cycle oil, dual oil coolers, upgraded water pump, radiator, etc. etc. Stay on top of the maintenance, run the car at 350WHP on lower boost set up inside the turbo's efficiency range, duct everything up and watch those air temps and water temps.
I love the rotary, I think the most likely cause of all these engine failures are people going over the limit of the engine or the drivetrain, the expectations are too high for the design. They sucked out all the margin of safety the engine had.....which leads to a very unforgiving engine. You can run a pretty nice single turbo set up for a pretty good price if you can find someone to help you select parts for the car. I am helping someone right now piece one together. He is almost done. We built the fuel lines ourselves, run EV14 injectors, bought an ebay intercooler for V-mount, modified a radiator already had, and I am tuning the car. We will be ducting it with .032" 6061 T6 AL. We also made the brackets for everything ourselves, pretty easy. I bet he only has 3-4K into this build. the car came with an upgraded radiator already, powerFC, better clutch, etc. We also dropped in a supra pump and rewired it, pieced the kit together ourselves.
I would run the rotary as it comes with the car and everything is designed for it. It's true that maintenance and upkeep are a huge deal with the rotary, running 2 cycle oil, dual oil coolers, upgraded water pump, radiator, etc. etc. Stay on top of the maintenance, run the car at 350WHP on lower boost set up inside the turbo's efficiency range, duct everything up and watch those air temps and water temps.
I love the rotary, I think the most likely cause of all these engine failures are people going over the limit of the engine or the drivetrain, the expectations are too high for the design. They sucked out all the margin of safety the engine had.....which leads to a very unforgiving engine. You can run a pretty nice single turbo set up for a pretty good price if you can find someone to help you select parts for the car. I am helping someone right now piece one together. He is almost done. We built the fuel lines ourselves, run EV14 injectors, bought an ebay intercooler for V-mount, modified a radiator already had, and I am tuning the car. We will be ducting it with .032" 6061 T6 AL. We also made the brackets for everything ourselves, pretty easy. I bet he only has 3-4K into this build. the car came with an upgraded radiator already, powerFC, better clutch, etc. We also dropped in a supra pump and rewired it, pieced the kit together ourselves.