twin turbo build for LT1 powered 89 RX7
03-11-13, 11:02 PM
#1
Trouble575
Thread Starter
Join Date: Feb 2009
Location: Texas
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
twin turbo build for LT1 powered 89 RX7
So I'm still sourcing materials and info but I'm getting ready to start building my twin turbo setup. I've had alot of people tell me I should be going super charged instead, but I've always wanted a turbo car and already had a supercharged car.
That being said I'm going to have to run remote mount turbos, I know I know turbo lag and I'm sure there will be tons of people saying I'm stupid for doing it this way. I'm not looking to make the fastest car out there, I'm doing this because I want something different.
Anyways I'll be posting pics throughout the project and would love to hear what you guys have to say, even if you hate it lol
That being said I'm going to have to run remote mount turbos, I know I know turbo lag and I'm sure there will be tons of people saying I'm stupid for doing it this way. I'm not looking to make the fastest car out there, I'm doing this because I want something different.
Anyways I'll be posting pics throughout the project and would love to hear what you guys have to say, even if you hate it lol
03-13-13, 10:29 AM
#3
2 things.
1. Why would you run remote mounted twins? Just run a single, there is no reason to add complexity.
2. Why do you "have to" rear mount it? You can put a turbo up front on an FC, no problem, I've put singles and twins in FDs and built a few single kits for FCs as well, which have more room than FDs, by a lot.
Here is an out of date picture of the location of one of my FC turbo kits. Would work a-ok with an LT1:
1. Why would you run remote mounted twins? Just run a single, there is no reason to add complexity.
2. Why do you "have to" rear mount it? You can put a turbo up front on an FC, no problem, I've put singles and twins in FDs and built a few single kits for FCs as well, which have more room than FDs, by a lot.
Here is an out of date picture of the location of one of my FC turbo kits. Would work a-ok with an LT1:
Last edited by digitalsolo; 03-13-13 at 10:31 AM.
03-13-13, 11:08 AM
#4
Trouble575
Thread Starter
Join Date: Feb 2009
Location: Texas
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
I'm running twins because thats what I want to run and it doesn't really complicate things any more than running a single, its just more work.
Im doing remote mounts because I don't see near enough room up front, and even if there was I can't find anyone near me that is willing to take on making the custom manifolds without charging me outrageous prices. Remote mounts solve that.
On top of that its my build and ill do it how I please
Im doing remote mounts because I don't see near enough room up front, and even if there was I can't find anyone near me that is willing to take on making the custom manifolds without charging me outrageous prices. Remote mounts solve that.
On top of that its my build and ill do it how I please
03-13-13, 10:18 PM
#6
nerd
Join Date: Aug 2009
Location: Lakeland Florida
Posts: 175
Likes: 0
Received 0 Likes
on
0 Posts
meh all you need is a sawzall, ball peen hammer and a cheap mig welder to cut/shape/tack your tubes together and then take it to a proper welder to seal it all up, belt sand the flanges and your all set.
remotes are a pita...fwiw.....
twins up front be lookin sexy and more responsive as well. just my opinion, i like twin turbo v8s...lt1 is a great engine to twin IMO, great torque already even in bone stock form will make huge power on a little +psi.
good luck though, we all need it at times
remotes are a pita...fwiw.....
twins up front be lookin sexy and more responsive as well. just my opinion, i like twin turbo v8s...lt1 is a great engine to twin IMO, great torque already even in bone stock form will make huge power on a little +psi.
good luck though, we all need it at times
03-14-13, 07:18 AM
#7
Junior Member
Join Date: Oct 2011
Location: ohio
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
My recommendation would be to put the engine in the bay first (with the radiator thats going to be in the car when complete) then judge how much room you would have to mount turbos and go from there.
Trending Topics
03-14-13, 01:01 PM
#8
Trouble575
Thread Starter
Join Date: Feb 2009
Location: Texas
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
Its not that I don't appreciate the advice/help but I am doing it the way I see fit. I already have my car built and running great, I initially wanted to do the twins up front but after looking at all my restriction with space I decided to go with remote mount instead. I already understand that everyone thinks it the "wrong" way to do it because of this and that, turbo lag being the biggest problem. I've actually seen a bunch of remote mounts done with zero lag.
03-14-13, 01:05 PM
#9
Trouble575
Thread Starter
Join Date: Feb 2009
Location: Texas
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
already done that, my car is complete as it is, I'm just adding turbos. I already know I don't have the room up front without doing alot of work which is the reason for the remote mount setup.
03-14-13, 01:06 PM
#10
ummm... being different is cool , being able to say you did something no one else has because they were to smart .. I dont knoww... LOL
I think unless you give a really good reason why you want a remote mount , you should take the advice given to you by digital look it over , and think for a bit ,
I think unless you give a really good reason why you want a remote mount , you should take the advice given to you by digital look it over , and think for a bit ,
03-14-13, 07:40 PM
#11
Let me articulate this better.
1. With regard to "rear mounted with no lag". Sorry, bullshit. You have more lag than you would with a front mounted turbo, that's just physics. Now if you size the rear turbo small enough, you can minimize the lag, but that just means you could have put a larger turbo up front with the same amount of lag and had more power potential.
2. Twins, when not needed for packaging or a class adds at least 25-30% more plumbing, more initial rotating mass and more things to fail.
3. Rear mount will require an oil scavenge system, and all the plumbing to get your returns back up front. If you thought you had to re-engineer a lot to fit the turbo up front, you're likely to spend about the same effort on the rear mount, for a less optimal design.
It's fine that you've decided to just do it your way, just realize that you're not necessarily making life any easier for yourself doing it this way, as well as introducing unnecessary complexity and additional modes of failure for the car. I'm an engineer, I don't like complexity for the sake of it.
FWIW, the only thing you should need to redo to fit a turbo kit up front on that car is the cooling system. I cannot speak to your abilities, but I can make those changes in about 3-4 hours. Honestly, I see 98% of projects that start with ideas like this never make it to fruition because people don't understand the level of effort required to complete it. That said, I certainly don't mind being proven wrong. I'll be curious to look at this thread in a year and see where you are on it.
Out of curiosity, how long ago did you build your swap?
1. With regard to "rear mounted with no lag". Sorry, bullshit. You have more lag than you would with a front mounted turbo, that's just physics. Now if you size the rear turbo small enough, you can minimize the lag, but that just means you could have put a larger turbo up front with the same amount of lag and had more power potential.
2. Twins, when not needed for packaging or a class adds at least 25-30% more plumbing, more initial rotating mass and more things to fail.
3. Rear mount will require an oil scavenge system, and all the plumbing to get your returns back up front. If you thought you had to re-engineer a lot to fit the turbo up front, you're likely to spend about the same effort on the rear mount, for a less optimal design.
It's fine that you've decided to just do it your way, just realize that you're not necessarily making life any easier for yourself doing it this way, as well as introducing unnecessary complexity and additional modes of failure for the car. I'm an engineer, I don't like complexity for the sake of it.
FWIW, the only thing you should need to redo to fit a turbo kit up front on that car is the cooling system. I cannot speak to your abilities, but I can make those changes in about 3-4 hours. Honestly, I see 98% of projects that start with ideas like this never make it to fruition because people don't understand the level of effort required to complete it. That said, I certainly don't mind being proven wrong. I'll be curious to look at this thread in a year and see where you are on it.
Out of curiosity, how long ago did you build your swap?
Last edited by digitalsolo; 03-14-13 at 07:44 PM.
03-14-13, 08:22 PM
#12
nerd
Join Date: Aug 2009
Location: Lakeland Florida
Posts: 175
Likes: 0
Received 0 Likes
on
0 Posts
^what he said...mostly...
trust me i get a little miffed when people troll my ideas when they dont see the big picture from my point of view, just heed the warning of remotes, they are a pita...
but if you are going that route look into a self contained oiling system for it, it works better and you can run more ideal oil weight for the turbo that way, and it solves a lot of the return oil problems, you can even put a retro-fitted oil level warning sensor in the reservoir to keep tabs on it.
it does add the need to drive 2 oil electric oil pumps, one for feed and one for scavenge, but if either fails you have a problem where ever you may be sitting...
the plumbing of under-hood twins is more involved yes, i know digital favors a single, but twins are super responsive when sized right....perhaps a bit too responsive at times.....mine is an absolute animal and its only on 6-7psi still....
im guessing you want to hang twins where the mufflers would normally go in the rear of the FC? if that is the case, you are going to need a very small snail on them, i used to build hybrid-ized turbos back in the day when aftermarket was scarce, and if you get yourself something in the neighborhood of a 50mm t4 compressor with an aggressive turbine side, like a garret O-trim around 52mm or so, and bore out a much tighter turbine snail to fit it, like a t3 snail in the .48 A/R range, like something you would run on a motorcycle build would make them come on fairly well that far back, also remember to keep your plumbing sizes to a minimum to maintain air/gas speed over the distance, too big of pipe will cause much loss over distance.
as for space constraints...i dont wanna hear anyone complain about space!!
trust me i get a little miffed when people troll my ideas when they dont see the big picture from my point of view, just heed the warning of remotes, they are a pita...
but if you are going that route look into a self contained oiling system for it, it works better and you can run more ideal oil weight for the turbo that way, and it solves a lot of the return oil problems, you can even put a retro-fitted oil level warning sensor in the reservoir to keep tabs on it.
it does add the need to drive 2 oil electric oil pumps, one for feed and one for scavenge, but if either fails you have a problem where ever you may be sitting...
the plumbing of under-hood twins is more involved yes, i know digital favors a single, but twins are super responsive when sized right....perhaps a bit too responsive at times.....mine is an absolute animal and its only on 6-7psi still....
im guessing you want to hang twins where the mufflers would normally go in the rear of the FC? if that is the case, you are going to need a very small snail on them, i used to build hybrid-ized turbos back in the day when aftermarket was scarce, and if you get yourself something in the neighborhood of a 50mm t4 compressor with an aggressive turbine side, like a garret O-trim around 52mm or so, and bore out a much tighter turbine snail to fit it, like a t3 snail in the .48 A/R range, like something you would run on a motorcycle build would make them come on fairly well that far back, also remember to keep your plumbing sizes to a minimum to maintain air/gas speed over the distance, too big of pipe will cause much loss over distance.
as for space constraints...i dont wanna hear anyone complain about space!!
03-14-13, 10:41 PM
#13
FWIW, I don't dislike twins. I co-built a twin turbo LS1/FD with a friend a little while back. I redid some stuff on another twin turbo LS1/FD for another guy also.
It's just that it doesn't really offer any advantages other than looking cool, unless packaging/rules dictate. If it's easier to fit 2 little guys than 1 big guy, by all means, it makes sense. My only point was that if you can fit one, and make the power you need, that's the most logical choice. On an anything close to stock LT1, a turbo like mine (PTE 76GTS billet) will make more power than the motor can handle, and it's a physically small turbo and really easy to fit in an FC up front (I could fit 2 on my car without much effort).
OP, I hope you realize that 85turbo12a and I are just trying to help with advice learned from experience.
BTW, just something to ponder... I once considered cutting out my bins and putting a turbo there. With cast iron exhaust manifolds and heavy piping (2.5") you could keep your efficiency losses a lot lower than a typical rear mount and not have to deal with fitting it in the engine. You still have plumbing issues and you have to fabricate a floor and reinforcements for whatever you cut out to fit it. I've got no idea what your skillset is, but that's just a random crazy idea for ya.
It's just that it doesn't really offer any advantages other than looking cool, unless packaging/rules dictate. If it's easier to fit 2 little guys than 1 big guy, by all means, it makes sense. My only point was that if you can fit one, and make the power you need, that's the most logical choice.
On an anything close to stock LT1, a turbo like mine (PTE 76GTS billet) will make more power than the motor can handle, and it's a physically small turbo and really easy to fit in an FC up front (I could fit 2 on my car without much effort).OP, I hope you realize that 85turbo12a and I are just trying to help with advice learned from experience.
BTW, just something to ponder... I once considered cutting out my bins and putting a turbo there. With cast iron exhaust manifolds and heavy piping (2.5") you could keep your efficiency losses a lot lower than a typical rear mount and not have to deal with fitting it in the engine. You still have plumbing issues and you have to fabricate a floor and reinforcements for whatever you cut out to fit it. I've got no idea what your skillset is, but that's just a random crazy idea for ya.
Thread
Thread Starter
Forum
Replies
Last Post
