Formula 89 Bird

I'm rebuilding 4-bolt main 350 from a early 80's truck that has alot of miles on it. I going to rebuild it and turbo the engine with a single turbo off a diesel. I have a few questions.

Frist since I'm getting it bored out here pretty soon, I was wondering what pistons to get, cuz I heard it is good to give the machine shop the pistons you want to put in so they can match. I don't really know that much about boring em out since this is my first rebuild. Also if I need new rods. I heard someone say the stock rods are good up to about 500hp. Is this true? Also, should I use the heads from the truck motor or use stock L98 heads and is it worth it, cost wise to change it to 2.00-1.60 vaules. And how much and what brand is good for a turbo cam, I read that you want less overlap, something like 220 deg@.050 intake and 216 deg exhast ground on 114 centers.

Second I am still deciding if I should remote mount the turbo(which would save alot of headaches)like what 89JYturbo
did or if I should make turbo manifolds. I have access to a MIG welder, and I like the idea of using the stock L89 manifolds and modifing them to mount a turbo on. But that was for twin turbos(http://www.geocities.com/kingtaling/turbo.html). I was wondering was I should use for the crossover pipe to the turbo manifold on the pass. side.

So my main question that I want answered if you don't answer any others is what are some good forged pistons that will lower my compression for a reasonable price($250-400) cuz have to get them soon to bore out my engine.

ALL opinions and answers are greatly welcomed. I have done lot of reading and on the power adder forum. And I have to found it to be best place for info on turbocharging a 350.
Thanks,
--Steve

MaxxMitchell

iTrader: (4)

What do you want to do with the engine/car? A race only app VS a weekend VS a daily driver will also decide on what you would need for the car.

On getting pistions for a fair price, i would check out ebay, some ppl will go forged, then scrap a project and then part it out even before the engine was assymbled.

Also what kind of fuel delivery are you planning on using?

Formula 89 Bird

Its a daily driver. Although most of my trips are to school and work(within 3 mi) no interstate so I don't really have to worry about fuel mileage to much. I know this sounds stupid but it has to be fast cuz I have to beat this guy at school that has a STI his daddy gave him. Soo I was thinking 400-500hp should be enough, although he has a few mods and like 10 more psi than normal so it isn't near stock.

I'm plannin on using the stock tpi intake w/ larger injectors and running the error code on the ecm, I can't remember the number right now. I was also thinking of swapping in a LT1 intake once I get it running. Thanks MaxxMitchell for the quick reply. -Steve

Formula 89 Bird

I'm thinking about using some TRW L2256 030 pistons. I guess I will lower compression by using a 70 to 80 cc on the heads.

Damon

Oh, it's an ugly disease, isn't it? It only gets worse with time, never better.

Can't help with the question (I've never built a turbo setup) but I can help with what you're feeling towards the STI owner. It's NOT stupid. It's fun. And it's good to learn to set goals. That's a very clear goal. People with very clearly defined goals usually achieve them. I have no doubt you will eventually achieve yours. Good luck with the project.

BMmonteSS

Stock rods are good to 300 hp, slightly more with arp bolts, any more and your on barrowed time. Thats what my machine shop told me and he builds motors out the wazzu for the local circle track guys, he knows his stuff. Stock crank should get you to 500, not much more.

I'm not sure what you mean by " running an error code" but that won't get you where you need to be with a forced induction setup. You need to learn to burn chips, which is time consuming and difficult, or get a FMU, which is crude but works.

I still don't know how you guys are welding cast iron manifolds. The only way I've seen it done is to other cast iron pieces with a specialty rod. Every book I've read says it can't be done. You have alot more learning to do if you really want to go with a turbo, their not a bolt on deal. You can bolt this thing on and get it running, but it will never be optimized unless you do some carefull planing and tunning with a wide band. If your planning on racing this kid from a stop your going to need a ton of work on the suspension and some drag radials. That AWD is a monster off the line.

Check out www.turbomustangs.com they have a GM power adder board and lots of good info. Check out their turbo bible, good stuff.

89JYturbo

Why not go with a twin turbo system, and modify the stock manifolds? I personally believe this will require less work than mounting a single large diesel turbo (speaking from experience).

If I had to kill a modded STIwith my daily driver, I would build a TT 350 using two T3 60 trim compressors and a .63a/r turbine. You can get new turbos like this for aroung $500 each, or source then used (but in good condition) for around $300/pair (they were used on 5speed T-Bird Turbo Coupes for a few years). I would also modify the stock manfolds to mount the turbos- this should support up to around 500-550hp.

My TT 89 IROC runs a bone stock, 95k mile L98 with a home brew turbo system. With very small T3 45 trim turbos, it has run a best of 12.4 @ 113mph (hot day on drag radials), and a 13.0 @ 117mph (cool day on street tires, poor launch). It should easily be in the 11's now with my T3/T4 Hybrid turbos (I plan to prove it theis spring!). You should be running at least 12.0 with a set-up like mine and larger turbos like the 60 trim T3, or even faster on a Super 60.

Links to info on my TT IROC-Z:

https://www.thirdgen.org/techbb2/sho...win+Turbo+IROC

http://www.turbomustangs.com/forums/...threadid=28286

https://www.thirdgen.org/techbb2/sho...+turbo+finally

Hope that info/pictures help. I'm sure you can get help here, we'll all want to see you kill that STI! (while spending less $$ to boot)

89JYturbo

Here is a picture of my stock manifolds modified for turbocharging:

(FWIW, I believe I pioneered this idea- I like it because it is simple, cheap, and effective!)

83 Crossfire TA

iTrader: (2)

Donno what to tell you, I’ve welded A LOT of cast bits and cast to steel stuff and with a little bit of care and prep it’s never been a problem. I’ve posted this pic before, but here it is again, this is a cast elbow welded to a steel flange. The other side of that cast elbow is sunk into the back of a cast exhaust manifold (took a 3” hole saw and cut straight into the section that it was going into) with a section of ¼” steel plate that I heated and bent to match the contour for the outside of the connection between the 2:


FWIW, this was done to fit a big caddie engine into a ’67 Lemans, and this car has been a daily driver for almost a year no with no issues with either manifold (the one on the other side was actually more substantially modified).

BMmonteSS

looks nice, can't explain it either. Might be the type of casting it is. I know if you try to weld an engine block you have to use a high nickle rod and go really slow to keep from cracking. My guess is the manifold is made from some kind of a high carbon casting so it comes out much more like steel and is more weldable. Either way it works. Your setup is a good example of what thinking outside the box can do.

IANTI

When fabricating a manifold is it a good idea to not weld the perimeter of the exhaust tubing to the flange completely but weld in four sections?



but the weld inside of the exhaust to flange completely welded in order to compensate for thermal expansion or is this useless?

Formula 89 Bird

Sorry I haven't replied for so long. I had a big long post typed out but my dad accidently deleted. Well I've gotten some more info on the turbo I might be using. It's TV6135 turbo off of a CAT diesal, my friend is selling it to me for $100 (whick is one of the reasons I dicthed the twin turbo setup), I'm pretty sure it won't need a rebuild. Anyways since my dad works @ CAT he was able to get me some compression maps for a TV61. I was looking at them and determined that a T-61 is a little too big for a 350. Now I read on other posts that T-6 or 7 is good for a 350 but by looking at the map it shows that I can probably only get 65 or 60% efficiency rating. It seems on the diesal turbos they like low rpms and high boost. So on to my ?'s

1. What does trim mean on a turbo? cuz I got 3 compression maps with 3 different trims (42-50).

2. Will the TV6135 work for my 350? or does anybody have anymore info on the TV6135?

3. Will stainless steel exhast valves really make a difference? cuz my friend(he's a mopar guy) said that SS valves will make a difference.

4. Does anybody know of a good place to buy dish pistons. I plan on getting my CR down to 8:1. There aren't to many on ebay and the best price I've found for forged dish pistons is $200 @ a local performance shop.

I plan on buys some pistons this weekend, so once I do I'll be somewhat "comitted" to going through with this turbo project. I think once I buy the pistons I'll start a new thread on my turbo project and update as I make progress.

Thank you to everyone posting, especially 89JYturbo.:yourock: I have read just about every single post of yours and you kinda of inspired me to start my turbo project.

83 Crossfire TA

iTrader: (2)

Post copies of the compressor maps. Besides the fact that some turbo geaks like me might get a kick out of seeing them, seeing them is also probably the only way that we could give you a real answer to your questions.



It’s usually a ratio between 2 dimensions on the compressor wheel. It’s also usually stamped/cast on the compressor housing.



WRT to things living long term, probably… OTOH, for severe duty in a turbo application you should probably be looking at inconnel.



For a set of 8? What pistons are those?

AJT86

ah man i know the feeling- its starts in highschool, gets worse in college. i finally just went out and bought the GN i was tired of having the V6 camaro in a college automotive class with guys with 2002 z28s and what not, its all about braggin rights.

f355bird

iTrader: (2)

One of my friends put a turbo on his 454 pickup that came off of a diesal. The problems he had was it wouldnt build boost above 3-3.5k rpms. Alot of the diesal turbos have exhaust brakes on them since they are designed for low rpms they will not hold the heat from higher rpms like a gas powered vehicles likes. Once the exhaust brake engages it is going to become a restriction. The best budget oriented way i could think would be to find cars that had factory v6's with single turbo's those are probably going to be the bigger gasoline turbos u will find. Get 2 of those and should be in business for a starter kit then u can build up more after u get all the bugs worked out. Tbird turbos would be cheap and easy to buy but grand national or syclone turbos would be better.

AJT86

i picked up 2 GN used turbos for 40$ each- no shaft play and no chipped fins or anything- im using them right now just to get my pipeing all figured out then i will upgrade later when the project comes together- look on ebay youll see GN turbos pop up alot- alot of guys swap them out even though they can put boost up to 24psi without problems- just older technology.