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Just wondering if any of you guys have see any lfx swapped rx8's.
There is a shop reasonably close by doing swap kits but not a ton of info out there about him. Anyone familiar with Keisler Automation?
Seems like a decent guy but always smart to do some homework first
I'm about to pull the trigger. These are putting out 280-300 rwhp and their cheap. The torque curve is flat as a board. I think it's going to make a great track toy
I'm about to pull the trigger. These are putting out 280-300 rwhp and their cheap. The torque curve is flat as a board. I think it's going to make a great track toy
There is a guy on here doing one in an FC, I think his thread is in the other engine swaps subforum
I'm intrigued by the swap. Have thought about it for a couple of years, even though I love the rotary. V8roadsters has done some miata's. I talked to them a couple years ago about doing an RX7 swap but they were too busy at the time to tackle it. 330+ HP, 7000 rpm, integral exhaust manifold (only one pipe to route on each side. GM electronics and aftermarket support. Forced induction kits available. direct port injection..light weight..Junkyard availability at super cheap prices...what's not to love?
oh yeah...that ugly intake manifold and terrible gear spacing in the transmission.
Post it when you do it though...and bounce me a PM. I'm not on here often but am very interested in the outcome.
He actually finished it about 3 months ago and runs it as a street car, but hasn’t had time to make a vid. He’s on RX8Club with the same username. Nice guy.
How to not be cheesy? Not possible so Ill keep it short.
I was heavily involved in the SCCA in the San Francisco region, if any of you competed at Castle AFB when the Fresno chapter controlled the site I was probably there helping with some part of the event. It was reputedly the best site in the country! Ive always been a rotary guy and chose the first gen as my platform of choice and began a journey to fully build the car to the max of what was allowed in CSP at that time. For some crazy reason about 12 ish years ago I moved to Pensacola Florida and it was pretty much a disaster of a choice financially speaking and I couldn't pursue any kind of motorsports. Lifes been good to me and I'm able to enjoy getting in the driver's seat again. Getting an 85 rx7 to the nationals is not important anymore and I have just been having track day fun. Here's the sexy beast at NOLA motorsports park.The realization that this car is now a collectors item, the parts are rare, I’m also older now and it's a tiny hot car with caustic exhaust fumes. This all signaled it was time for an update.. The Rx8 is a smoking hot deal as far as chassis go right now. I have a good roller that I was going to build up with an NA street port 3 rotor. Did I mention I love the rotary? Then I realized how much more expensive the rotary had gotten in the years I'd been away from motorsports. My friends quickly convinced me that an LS swap was the way to go, I figured 12-18 months of spare time and I could have an engine swapped car but it's fairly expensive to purchase one and get it in any kind of shape to compete on track. It also had more power than I desired.. I follow the miata forums, those guys do everything and have a pretty wide knowedge base. I noticed some miatas were getting a GM v6 swap and started looking into that as an option.
7500rpm redline, awesome powerband, easily, affordably and reliably makes 320whp.
<insert dyno here>
Perfect! Exactly what I wanted. Now I have to figure out how to make this happen. After many many hours of googling things I decided to reach out to Kiesler Automation.
I first emailed Andrew in late September, then started heavily asking questions and pursuing the idea mid to late November.. After much back and forth Andrew and 3 options on the table. I decided to use a car Andrew had on site and have him do the entire build for me. Quite the opposite of the original plan and some 200 emails later on February 16 I flew to Knoxville, picked the car up and drove it home. Sounds pretty easy. To good to be true even! Its scary as hell handing over large sums of money to someone you dont know, have never heard of and don't even have a known good source from a forum vouching for him. Scary! I paid about 50% up front and was pretty sure I'd be fighting to get my money back. I ended up having a great experience
The build Did I mention I've never driven an rx8 and have no experience with them?
2004 rx8(no sunroof)
Kiesler’s willwood front brake kit (stock rotors better calipers)
Kieslers track pack
Lfx 3.6l
Jackfab intake manifold mods
Radium Catch can
Single exhaust. Andrew said duals wouldn't fit in an optimal way. I was doubtful about that till I saw it. Exhaust video
4.10 diff, clutch pack LSD (I prefer clutch style so hell yah!)
Spec aluminum flywheel/clutch
Penske double adjustable shocks and associated hardware
800/550 springs
Camero mv5 Transmission
Titan 7 tr10 18x10’s with federal 285/30 100tw tires
Impresions I spent 7 hours driving home. First leg of the trip was 2 hours though a national forest (mountains) the remainder was interstate. The trip was great and the car performed flawlessly.
I got 27mpg though the mountains and 29mpg on the interstate going 75mpg. Pretty crazy for a performance machine! I didnt plan on driving it much on the street as it was purchased primarily for track use but it is so much fun to drive that I have taken it to work a few times and when I have to run errands. Honestly it's the first time in a long time that I look for excuses to drive somewhere. I'm a huge fan. The power delivery is fantastic. It's not overwhelmly powerful feeling like a v8 car.
It's more like a well setup turbo 13b or a small supercharged engine.. There is torque everywhere. You never have to downshift to pass. The 4:10 gearing is an excellent choice. You can see the ratios and charts above.
Its perfectly manageable for street driving but was really chosen with track duty in mind. The pedal placement in this car is phenomenal! The car is loud. 105-113db on on my spl meter
Most of the peak spl readings are to be had under 4k rpms where you get that v6 rasp and the drone zone. If you live or race anywhere with sound restrictions spec out your own exhaust parts. If your old and just dont want the extra noise, spec out your own parts. I'll be changing mine up. To be fair to Andrew, exhausts are subjective and its really crapshoot of getting what you want out of what you bought. The exhaust sounds good most of the time and really good when going fast. The clutch
Personal preference item here, but I hate a clutch that engage/disengage at the top of the pedal throw. I just cant drive it smooth. Once I got the car home I adjusted the pedal/master pushrod to put the action at the bottom of the pedal. The rod is actually a little to long and I will eventually take it out and shorten it slightly. I was still able to adjust everything very close to ideal for me. Transmission
I had some trouble getting used to it. Combined with my clutch comments above I wasnt thrilled at first. Occasionally its hard to get into 1st. This seems to be a common complaint of this transmission. I initially thought i was missing the gate, or hitting reverse. I had severally really uncool moments at green lights feeling like an idiot that didnt know how to drive. Once I got the clutch adjusted the transmission also felt much better. I probably just got used to it. It feels pretty good now and under street conditions I can snick up an down the gears without issue. I dont notice the first gear issue often now either. When I do i just go to second then put it in first with no issues. Brakes
FANTASTIC. A friend of mine drove it on the street and it took a few for him to get used to the brakes. The car stops so fast that its very easy to stop early if your not accustomed to it.
The pedal feel is great, feel and ability to modulate are spot on. Unfortunately covid happened. I haven't had a chance to attend any sort of event and I haven't gotten the car on a Dyno to see what it's really putting down. Upcoming updates will be a wing and splitter.
I'm also looking into redoing the exhaust using burns/coastfab/profab parts.
I don't mind sharing. I would like to say I'm a fairly early adopter of this kit so the price may change over time but I don't expect the type of guy Andrew is to change so I suspect everyone will talk away feeling like they got a great deal.
I paid just under 23k for everything
Wheels were a separate purchase and not included in the price.
What are the advantages vs the ls platform ?
Looks like same weight, comparable redline, less aftermarket support, less power and a worse transmission, no ?
it can handle 7500rpm all day long an ls cant
Way more useable powerband
no need to build custom headers
It's about 100lbs less weight
3-4 inches shorter
It costs 400-600% less for the engine
the transmission is very good and also significantly cheaper.
e85 ready
only makes about a 100hp less than an ls
Power to weight makes this a perfect tt3 car that I could also use in SM
Another bonus is the swap is very well thought out.
For next to nothing more you could have ac, use this as a 300+ hp street car that gets 30mpg. It drives and behaves like a normal car. There are no quirk's.
it can handle 7500rpm all day long an ls cant
Way more useable powerband
no need to build custom headers
It's about 100lbs less weight
3-4 inches shorter
It costs 400-600% less for the engine
the transmission is very good and also significantly cheaper.
e85 ready
only makes about a 100hp less than an ls
Power to weight makes this a perfect tt3 car that I could also use in SM
Another bonus is the swap is very well thought out.
For next to nothing more you could have ac, use this as a 300+ hp street car that gets 30mpg. It drives and behaves like a normal car. There are no quirk's.
Your list looks a bit, optimistic.
-Most mild build ls’ shift at 7k.
-The ls has more power everywhere in the powerband, and is more linear.
-no headers and no leaky v- bands would be nice for sure
-the ls is 60 pounds heavier, both fully dressed.
-2.75” difference in length.
The big question here is does it eliminate the need to relocate the steering rack in an fd, and avoid the outboard bumpsteer correction that comes along with moving the rack ?
-you purchased an lfx for less than $500 ?
-e85 compatibility would be a bonus, but mainly if you were running fi, which is a liability on a track car anyways.
-A na build lfx manages around 300whp ( not much aftermarket, they are pretty optimized in na trim really ). An ls3 with a cam and supporting mods is 500whp. That’s a pretty big difference. The difference between getting positively dusted down the straights.
I don’t see the 60 pound weight difference and 2.75” block length negating that advantage.
I’m not being hypercritical here, just looking for accuracy and clarity. I’m actually trying to talk myself into something like this.
The heads/cam/intake ls in my fd is best described as excessive for what the car needs.
400whp would be the sweet spot. If the lfx could do that in na trim I’d be all in.
LS is 497lbs full dress weight.
LS is 24" from back of block to crank pulley and 27.5" to front of accessory pullies (alt, ps, ac overhang 24" crank pulley length).
LFX is 345lbs full dress weight.
LFX is 20.3" from back of block to front pulley and 26" to the front of the throttlebody (so plastic intake maifold and TB overhanging 20.3" crank length).
If you think 500hp will make your car better than 300hp by all means go LS.
Buy the Sikky LS swap kit because they figured out you just need a custom oil pan to use stock FD front subframe with stock steering rack location with an LS. No more hillbilly gokart v8 swaps necessary.
LFX in FD doesnt really make sense to me since 13B-REW is so cheap/easy to make 300rwhp reliably.
Makes sense in Miata or RX8 though where 13B-REW swap is very complicated (single turbo upgrade + swap).
LFX swap is for people who dont think much more than 300hp will make their car better, but anything to help chassis dynamics will.
Makes sense to me. Substantial weight difference, further back in the engine bay, packaging advantages aside. If more than 300 hp were needed I'm sure it would be easily available with forced induction.
Ntm are you trying to convince me I made the wrong choice?
320whp is easily obtainable on the stock engine. 340 with cams. Like I said, my power to weight ratio is perfect for tt3 so peak hp doesn't really matter to me. I can easily shed 100-200 lbs or pickup 20hp from where I'm at.
Peak torque at 2500 rpm and flat to redline. Very similar to driving a rotary. It's very easy to control.
You keep referring to a cammed lsx. That's not stock. Also if you want to rev it high regularly your going to be changing other parts but there is no point in doing that, 2500-6500 is a fine powerband if that's where your engine works. If you want it to survive high g sweepers road racing there is some more expense.
It's not that an ls cant be bad ***, but it's expensive, even more so if you want to beat it up in a racing environment. a used aluminum ls is 3000-6000 easily. 900 dollars for my lfx with 15k miles on it.
Anyways my choices won't be everyone's. I have no regrets with the route I took, all my check boxes got ticked.
Blue, I'm sure more than 300hp in an rx8 would be a blast.
its just not necessary in all cases. Bumping to say tt1 or tt2 would be expensive. More power, more speed, more tire, more brakes, more safety
Ntm are you trying to convince me I made the wrong choice?
320whp is easily obtainable on the stock engine. 340 with cams. Like I said, my power to weight ratio is perfect for tt3 so peak hp doesn't really matter to me. I can easily shed 100-200 lbs or pickup 20hp from where I'm at.
Peak torque at 2500 rpm and flat to redline. Very similar to driving a rotary. It's very easy to control.
You keep referring to a cammed lsx. That's not stock. Also if you want to rev it high regularly your going to be changing other parts but there is no point in doing that, 2500-6500 is a fine powerband if that's where your engine works. If you want it to survive high g sweepers road racing there is some more expense.
It's not that an ls cant be bad ***, but it's expensive, even more so if you want to beat it up in a racing environment. a used aluminum ls is 3000-6000 easily. 900 dollars for my lfx with 15k miles on it.
Anyways my choices won't be everyone's. I have no regrets with the route I took, all my check boxes got ticked.
Blue, I'm sure more than 300hp in an rx8 would be a blast.
its just not necessary in all cases. Bumping to say tt1 or tt2 would be expensive. More power, more speed, more tire, more brakes, more safety
Not at all, I’m trying to get you to convince me to do this swap 😁.
I like the performance of the ls, but it’s a bit over the top. Especially for a chassis like the fd.
It’s not smooth, it’s loud, with h/c/i it’s too much power, I find myself pulling timing at lower rpm to make the power more tractable.
Camming an ls is kind of a given since it’s so cheap to do, and easy with the engine out.
Blue- On ls weights, I actually weighed my ls1, fully dressed with ps and ac. I don’t know what you’d have to bolt to it to achieve 500 pounds.
Perhaps the factory manifolds are 60-70 pounds ?
And the bump steer correction isn’t a big deal as long as you actually take the time to measure it and correct as necessary. Most people do not, and a couple mm of vertical displacement has a large effect. Heck, just changing caster a little effects bump steer. Interestingly, the factory setup actually has a fair bit of bump steer/toe gain on an fd.
Sikky isn’t super popular because it mounts the engine slightly higher than the typical samberg style.
And you have to beat the hell out of the firewall to get it back enough to clear the hood.
Personally, I’m super interested to see just how well one of these lfx’s fits between the rack and firewall on an fd.
That's good to know, changes the discussion quite a bit.
I guess it depends on your goals. What are you going to do with the car? Maybe an ls is exactly what you need.
I think the LFX would be the perfect motor for one of my REPUs. There isn't a lot of room in a REPU. The aluminum block like I have in my 2017 Colorado would be a fun project.
That's good to know, changes the discussion quite a bit.
I guess it depends on your goals. What are you going to do with the car? Maybe an ls is exactly what you need.
Mainly just a weekend street car with 4-5 lapping days per year.
With the ls, it’s not the kind of car a guy would take on a long trip.
