Hey, although I'm not serious about it yet, I plan on doing my own TT set-up on my car within the next year or 2. I have a 4 bolt main 350 right now with 2.02 heads. I have an idea for a set-up, but I'm not sure yet:

1. Turbo manifolds from here.
2. Some Junkyard Volvo Turbos and DV's (or any other brand, whichever you think will work best)
3. Two intercoolers and aluminum piping (undecided what I'm going with yet, I will run 2 though, possibly some junkyard ones if I can pick them up)
4. Obviously some piping from the turbos to the carb, and to link the trubos together (however you do that)
5. Oil lines, if some one could tell me exactly where these run from and to, that'd be great.

Now, do I need a new carb? I know I'll need a bigger carb (most likely 700cfm) once I get to the turbos, but will I need a special kind for the turbo? I'm running a pretty big cam in there right now, the idle is very lopey, is that okay or should the cam be swapped out? Also, I'm running an edelbrock performer intake manifold, will that be okay too? The car has no computer on it, so do I need anythig special for the turbos or anything besides a gauge to moniter it?

2 last questions, about how much do you think this'll run me? I was thinking about $2,500 since all the piping and everything will be done by me and a lot of the stuff (turbos and possibly intercoolers) will come from junkyards and ebay. Does that sound about right? I was planning to run about 10psi of boost, does that sound okay or no?

 

It will be best to swap to a turbo specific camshaft and a carburetor modified for blow-through turbo operation.
You'll need very good quality fuel pump and lines.
You might want to start with a lower boost level without intercoolers to simplify the project and then add on later.

 

I found 2 cams from comp cams, one is .540/.563 lift on the factory rockers, it's usable power range is from 3,000 to 6,500 rpm. The other cam is .563/.563 and has a usable power range from 3,500-7,000 rpm. Are there any lowe lift cams, I'd like some vacuum for the power brakes, plus a little more low-end power.

Are turbo carbs the same kind of carb used on superchargers? 'Cause if it is then I now what your talking about.

Should I maybe run like 6-7psi without intercoolers first? What will the power gains be like on that set-up?

 

Supercharger cams will work but not optimal for a turbo motor and a stock cam works surprisingly well to get you going or Camotion seams like the leader in turbo cams at the moment, I have a 4 bbl throttle body but most of the guys over at turbomustangs.com like 650 double pumpers modified by CSU for blow through and they are making some big hp numbers.Also 6 psi will be very strong.I boosted a 307 to 15 without an intercooler using water injection untill it blew the cast piston but it was damn strong for about a month.

 

order a custom grind after consulting with an expert.
If on a tight budget a stock cam will work very well. The hydraulic rollers that cam in the 1988 - 1992 L98 350 TPI engines should be a good cheap place to start.

The carb is modified for blow-through duty either supercharger or turbocharger, but not the kind of carb that goes atop a rootes blower.. that's different.

You can roughly expect about 33% power gain from 33% added atmosphere.... usually a little less, but I said roughly.

 

The lift isn't what affects your vacuum for brakes.
You will probably be best off with a stock cam at first.

Once you start increasing the boost & backpressure, it's time to consider a custom grind.

Turbos generally respond best to very mild camshafts, although you can turbocharge any engine combination. A poor cam selection will just produce less power, make tuning more difficult, and leave power on the table.

 

Like 305sbc said, turbo friendly cam, blow-through carb, and an upgraded fuel system. Also, you can get the oil to the turbos by 'T'ing into the line where the oil pressure sending unit is. From the turbos the oil returns go to the oil pan.

A couple gauges you'll need are a boost gauge and a fuel pressure gauge. The intake manifold is fine.

The price estimate seems reasonable if you are going to do most of the fabrication yourself and are able to find the turbos/intercoolers from junkyards.

How much you'll have to upgrade depends on how much power you want to make. 10psi of boost that's intercooled will be alright.

Also, don't forget that you'll need wastegates to be able to control the amount of boost.

 

Wow, I've already learned a good amount from this thread already. If you look at my user info though, you'll notice it's not a third gen's 350. It's out of a '69 or '70 camaro, most likely a Z28 do to the fact that it also has 2.02 heads.

I'll defintely check out the people you mentioned for cams, and I'll keep researching carbs. All this stuff osunds pretty good so far. I'll probably start off with about 7psi of boost though and then work from there when I get intercoolers later on.

 

i've heard really bad things about SSautochrome. with the things i've heard i would sooner make my own manifolds than buy thiers.

 

Here's a link to an example of a turbo cam from LPE.
Scroll down the page til you get to the GT7 cam. This is the LS1 version of a cam designed to work great with a turbo.
http://www.lingenfelter.com/store/c31.html

Using a larger exhaust valve also helps. Some go as far as installing the larger BBC valves because they can survive the heat better.

 

Not like just about anything cam timing wise for an LSx engine really applies to a gen 1 or 2 SBC…

 

Comp lists 2 turbo cams in there catalog. Either should work well with you listed specs. Once you move up to bigger heads and turbos you can look at bigger cams.
Go to Turbomustangs.com and look in there carb section.
There are a lot of mods listed you can do your self if your able and save some cash. Your boost level will allow you to get away with things that wouldn't work at higher boost levels.
For a low boost 350 you might get away with a 600DP.
There's people doing 8's with a 750 just for comparison.

 

What about a single trubo set-up? Wouldn't that be a tad cheaper and still produce good power? I was thinking a T3/T4 hybrid single set-up like this:

1. T3/T4 Hybrid Turbo that I can get from a friend that runs both a 450rwhp 2.3L SVO Stang and a 600rwhp 2.3L in a Turbo T-bird.

2. A single, good sized intercooler.

3. A decent 10-12 psi of boost.

4. Some turbo manifolds/headers

Does that sound like a decent set-up? Better then the first? What I can't figure out is how I would route a single turbo though? On a V8 at least I can't. HOw did they set themup on the TTA's or GN's? Anyone know if this is any more beneficial/powerful then going to a twin turbo set-up with dual Volvo turbos? Will it be more reliable? Am I better off just sticking with my first set-up?


Allright, I'll check those out, I think they might be the ones I was talking about on Summit.

 

You don't want to run a 2.3L turbo on a 5.7L engine; 2 maybe, but not one. The choice between single or twin is something that you will have to decide which will be better for you; that will probably involve doing some searching.

 

first off you need to learn as much as you can about the egine you have. knowing that will help with setup specs. just because you have heads with 2.02 intake valves doesnt mean its really anything special. and to be honest if they are stock heads from that time period, they arent even good either. i am not impressed with any heads from that era unless you stumble across a set of porcupine heads which i believe werent ever released. next thing, if its from a 69 Z28 then its not a 350. or if its a 350 its not from a 69 (or any first gen) Z28 for that matter. the ONLY powertrain option for the first gen Z28 was a 302/4 speed combo. for rules allowment in the trans am racing series. you also need to find out what kind of internals you have as well as compression ratio. basically find out every measurement for every part of that engine. knowing that will help you source out parts easier.

next thing, ssautochrome makes decent parts so long as they are for supras. everything else ive seen cracks and breaks UNLESS you make some supporting mods to the actual manifolds themselves.

as for turbo sizes, you cant buy a t3/t4 hybrid. or nto atleast just that. you also have to pick out your comrpessor wheel trim, your exhaust A/R and inlet size. this is stuff you need to learn before you tackle this project. after you learn what you can about turbos, i would start thinking about what kind of hp you want and what kind of boost levels you want to run. then pick out a turbo based on that. when you know those things you can look at compressor maps for different turbos. example, sure you can bolt on say a T76 turbo and make 400rwhp (hypothetically here) at like 10 psi but it will spool slower than say making 400rwhp on an sc61 turbo at 20 psi (again hypothetical here). but that t76 turbo will support more horsepower later.

also DO NOT ask how much boost yuor engine can take. boost is ONLY a measurement of air intake restriction. think of it like a car tire. you can put 32 psi in a tire designed for say a civic and 32 psi in a tire designed for say a silverado and even though they are both at the same psi level the silverado tire will have more air. that 32 psi in this case is a measure of pressure and pressure is a measure of resistance. boost doesnt kill your engine. extreme loads (caused by higher horsepower), bad tuning and wornout/bad parts do.

after all that stuff heres the real answer to your question. your needs are different than mine. mine are different from joe blows down the street. pick the setup that best fits your needs/wants/budget and you will have the most fun.

 

when picking a cam ...you want less overlap . Find out what you got . I can;t believe I am gonna say this but ...try the search button . Or hit the stickies atop this forum , there is ALOT of stuff to sift through . I myself am going single turbo . It's all I need . remember you don't need two to make power .... when stuff is matched ....it's going to perform . Check out some posts of other guys on this forum .... read some sigs .... PM some people . Get a couple books .

I JUST got into this all myself and have taken the above advice and learned alot along the way . But still have GOBS to learn .... but getting there is half the fun


P.S don't be in a hurry or you will have nothing but a half assed setup that runs 12's and a stomach full of ulcers . WIth alot of questions like WHYYYYYYYYYY ?

Peace out

 

ive always heard its better to run more duration and less lift because first and foremost a smaller amount of lift is easier on valve springs. you also dont need the valves opened up a large amount like you do on an NA setup because the engine isnt using its vaccuum from the intake stroke to pull in the intake charge. you just need the valves open longer for the air to be pushed in.

editted to correct my stupidity. lol.

 

I may be wrong here so someone correct me if I'm wrong. Overlap means there is time when both valves are open. You want the exhaust to shut sooner to catch more boost.

Not for sure I'm a bodyman not an engine man

 

i meant duration. i read overlap and thought duration. im retarded. ill go back and change my last post to be correct.

 

dont run the ssautochrome stuff. Its total junk. Its a big ebay company. Its all built really cheap. They also use low quality material.

 

Well I've been researching a lot lately. I think I have an idea of what I'm going to do, but I'm not 100% sure yet. The reason I said twin turbo as opposed to single is because I figured it would be eaasier to build and fabricate.

1bdbrdp- I don't think I ever said it was from a Z-28. If I did, I'm not sure why I said that, I know that first gen Z's only came with 302's.


Also, this project isn't planned for a while. Probably about a year away, just trying to gather knowledge on it. Thank you for your help. When I do pull the engine in about a year or so, I plan on doing either a turbo'd 355. Or possibly a blown 355. I'm not sure which yet, but as you can probably guess, I made a thread about this and not superchargers, because I'm considering this a lot more. And obviously, turbo will be a harder project as opposed to just some twin screw blower.

Thanks, for you help, I'm gonna research some more, and post my findings/questions.

 

this doesnt have a whole lot of worth here but ive yet to see how a properly braced SSAC setup is as bad as its made out to be on this board. theres a few supra guys running them with no problems as well as people running a turbo swap lexus. some honda guys have problems with them but if they are braced the second time around the problems dont reappear.

 

The only reason I say that is cause I have been screwed by there junk. I have personally bought a turbo from them and it lasted a whole 10 minutes. And I was out my money. So I think you can understand why I dont put business there way.