Quick update.

Good news first.

I'll have room for the GT45 with some minor rearrangement of my engine bay (pusher fan instead of puller setup I have now, and likely relocate the driver side coil packs) and some creative manifolds (not an issue from a skill stand point, maybe one because of physical limitations). I had toyed with the idea of just building a high compresion 402, but I'm going to forge ahead with the turbo project and see where it takes me.

Bad news.

The truck manifolds I purchased are worthless. Anyone who had hopes of recreating a "cheap" turbo setup for their LS1FD is going to be dissappointed. Both sides do not fit turned backwards. The passenger side has a flange that is too large that will not clear the frame rail/cylinder head/heater lines. I could probably make it fit by lifting the motor up and sliding the manifold in, but the heater lines would still be an issue. It'll be easier to just make a custom manifold.

The driver's side points right into the power steering pump, requiring removal of PS (which I'm doing anyways), and relocation of the alternator (not a big issue IMHO), but...as long as I have to make one custom manifold, I might as well build the other to match.

Also, there's no prayer of running a 4" downpipe. Too tight. I'll only be able to run a 3.5" downpipe, which is fine because the outlet on the turbo is 3.3" (custom V-band flange I had made will weld right up to a 3.5" pipe). I don't think it'll affect things too much. It might punish spool time and top end power a bit, but I don't it will affect the amount of "useable" power I'll make.

Pictures to come (and I'll likely start a new thread about it) once I get started.

 

Great information, keep us posted as it gets farther along. Too bad about the 4" though, maybe with a tad smaller turbo? The Gt45 is pretty big. As as you get that in there I want pics! Also thanks for the information on the pusher fans, I will set mine up that way when I install the LS1 from the get go. Hope I can fit a large FMIC with pusher fans and a radiator that far forward.

 

Size of the turbo has nothing to do with whether a 4" downpipe will fit or not. Clearance between the block, passenger side motor mount, and the frame rail do. If you figure you need 0.25"-0.5" clearance on the frame rail side to account for engine movement under throttle 4" just isn't possible without touching something. There's also the little matter of clearing the starter and allowing enough room for a heat shield to protect it (unless you only want to start your car once )

My OBX FMIC is a full 3" core, and I'm hoping it will fit just fine with a pusher fan. Another one of these things I won;t know until I get in there.

 

Just "neck up" to 4" after you clear the engine, if you want to run 4" to the back of the car. There will barely be a difference in power potential using a stepped setup like that.

Another option is to use oval pipe...
http://www.burnsstainless.com/OvalTu...valtubing.html

 

Yeah, thanks Jim. I've considered both of those options.

Like you said, I don't know that necking up to 4" will actually gain me that much, and since I'm making my own catback anyways, and the components are readily available in either 3.5" inlet/outlet or 4" I don't know that it makes too much sense to obsess about running 4". The outlet on the exhasut housing is 3.3" anyways, so necking up to 4" v. 3.5" might not improve flow that much.

Oval is a good idea too, except that I'd need to transition from round to oval, and then back from oval to round. No big deal, and certainly something to consider.

I've got a ways before I have to decide about either though.

 

If you modify the passenger side of the subframe, you may be able to fit a 4 inch down pipe in there.

With some work you could relocate the starter to the opposite side of the engine but it would be a pain in the ***.

 

Thanks god they aren't asking me anymore.

 

ha, I rode with you in an Auto-X about 1-2 months ago at Tech Ridge. I told you I had a modified red 2nd Gen.

 

Umm...Yeah...I won't be modifying the subframe or relocating the starter. I'll just have to live witha 3.5" downpipe.

If I'm going to have to totally reengineer the car I'll just sell it and start with a tube framed chassis or something.

Thanks for the suggestions though.

 

Your next ride along should be more fun.

 

 

Yup, got one of those. I think my plama cutter would be better suited though.

 

http://www.turbomustangs.com/turbogm...mouse/dyno.jpg

How did I miss this thread till now

And I was hoping to be special

 

This is what we affectionately refer to as a tease.

I did a little work in the garage this weekend. Thought I'd share.

Ignore the shitty *** welds (the tubing is giving me fits because it just won't flow into a nice bead, I'm about to give up and go to stainless). I forseee lots and lots of work with the grinder to get everything pretty in the end. Then they're off to Jet-Hot for some 2000º coating.

enjoy

 

Have any of you guys working on a turbo LS1 considered something along the lines of what STS does?

http://popularhotrodding.com/tech/0411phr_sts/

Baically, put the turbo closer to the back of the car. I'm sure it adds a little to the spool time but with the off idle tq you guys have it doesnt really matter. If you check out the link down toward the bottom they have a dyno chart and it shows that it starts to make more tq than stock at about 2800rpms with the boost really hitting hard and the tq just pulling away from stock by 3300rpms. With a setup like this you could just use whatever headers will work and regular exhaust all the way to the back (this means cheap). Then mount up the turbo close to the diff wherever there is room and run a IC pipe back up to the front. I dont know what turbo they were using but the dyno shows 500rwhp @ 7psi.

Sounds reasonable to me. Maybe not the absolute best in theory but it works well and it should be much easier since you can use more off the shelf type stuff.

just an idea for some of you guys to throw around in your head

Later,
Stephen

 

You have to remember that he's running a GT45. Sure the rear mount will spool a turbo just fine if you're working with a small turbo. The GT45 will probably produce full boost by 8000rpms mounted in the rear


Andrew, looking good although it would look better if you had a T76GTS

 

Yup, I've seen it. I'm not a big fan. Most of the "customer" curves don't look as good as the ones in the PHR article.

There's a couple issues with using that type of setup on our cars. The biggest thing I can see is where to route the plumbing off of the compressor. There isn't a tone of room next to the block, and what's there will be taken up byy headers of any reasonable size. That means you'd have to route the plumbing under the engine, creating a ground clearance issue.

Add to that there's more room at the rear of an F-body (our cars are considerably smaller), and there'd be packaging issues with a rear mounted turbo. Also, as John said, with my current turbo i'd have such sever lag it wouldn't be a wise choice. I'd have to move to something much smaller just to get it to spool. I wouldn't want to go through all that effort and limit myself to 500rwhp, which will be nothing for the turbo I've chosen.

I certainly wouldn't criticise someone for choosing that route and making it work on their FD though. And 500rwhp is nothing to sneeze at. I don't think you'd find too many people that would turn it down. I just think I can do better is all.

 

Unless you want to trade straight up, it's going to have to be a gt45 for now. It looks like it will fit no problem, we'll just have to see what the spool is like.

 

What size turbos do they use with those kits? Anyone know?

 

T60 ususally. THough I've seen some t-62, t66 and t70 upgrades as well.

 

Do you know what they were using for that dyno chart in the link I had? A T70 would be a large frame turbo, how do the charts look for it? But yea, you guys are right there might not be any room to do that set up either, it just seemed like there would be more room for that type setup verses keeping it all in the engine bay. Also keep in mind since its a RX7 it would probably be closer to the engine than in a Fbody so the same kit might spool a little better for you guys than the Fbody guys. If someone has access to tig welders and everything and has the time and skill then they would definatly come out better doing thier own. I thought this might be good for someone that cant make custom headers since thats probably the hardest part. They could just use any off the shelf headers that will fit on the car.

Anyway, I'm curious to see what some of you guys come up with and what kind of power you make.

Stephen

 

SPO wants to come to the dark side!

I've been monitoring these guys on 3 different boards. I'm waiting for someone to do what i want (cuz they have the money to spend on stuff if it goes horribly wrong) then follow suit. I'd plow my own way, but that's really expensive. I rather just give credit to those that push forward with these v8 swaps. I thank them because I don't see any car under 30k (cept maybe A c5 corvette now lol) that I would like to have except the rx7. The rx7 is just so sexy!

Looks really great! Keep us posted folks

 

And those off the shelf headers would be?

Unfortuantely that's one of the biggest issues. You're pretty mjuch stuck with stock manifolds unless you can make your own, score some of the elusive Hinson Long Tubes, or get in line for the (currently vaporware) Sanderson headers.

That makes two of us.

 

three even.

 

Those headers look great...

I talked about the STS stuff a while ago and it was highly frowned upon, but they do seem to work.

Their torque curves are no worse than some of the SC cars out there and I'm not sure who here has driven a high RWHP Turbo car its gonna be tough to handle all that torque down low.

The STS route seemed perfect because it would not create a ton of torque downlow until your moving.

With the LS2 pricing, and hopefully the upcoming LS7 block prices NA seems to be a bit more of a stronger candidate unless someone has some piping they'd be willing to sell

The car is up for the winter in the garage, but I have to decide on something by January to get it going for March-April.