Ok so I posted about doing a twin turbo setup on my 88 Iroc 350TPI. All of you responses were very helpful. Well, I have decided to buy single turbo a kit off of ebay. I have seen this kit before but I don't know who makes it. It consists of a New T-4 turbo, two manifolds, a crossover pipe, wastegate and some other odds and ends. All of the manifolds and exhaust stuff has been HPC coated so that's nice.

Now for a few questions, This kit is intended for a carb setup but I have a TPI so it shouldn't be that hard to plumb. What should I do to keep the fuel to air ratio the same? My engine is speed density, can I just raise the fuel pressure way up? I have some LT-1 injectors, would those do? Ahh and what is a FMU? I have seen some on ebay but I have no clue what they do?

Thanks Again for all of your help. Classes end in three weeks so I can begin the trek to boost land.

Oh yeah here's the auction http://cgi.ebay.com/ebaymotors/ws/eB...category=33742

 

If Im not mistaken, it looks like a draw through kit. STAY AWAY!

 

Why is that bad?

 

I'm not using the setup as a draw through so that cancels it out as being bad. Any other comments?

 

thats the turbo kit off of a 81 turbo TA. theres a turbo ta in the local junkyard by me and well thats the worst set up. its not worth the money. ull probably spend more modifiing it then u would just to buy it and convert to carb.

edit: and if u look at it ur only gettin the manifold with the turbo flange on it , the other side u will have to run a header enless the guy has the other manifold.

 

Ok yeah the guy has ALL of the parts, the other manifold, everything. I am NOT converting my car to a Carb setup. I am retaining my TPI. The turbo is new, there is a new waste gate and all the stuff has been HPC coated how is that not worth it?

 

are u good at fabricating new pipes to reroute the way the turbo i guess u can say flow? becuz im not positive but im pretty sure how the turbo sits on the flange the turbo housing (i dunno what its called) will be either hittin or be in the middle of ur TPI plentum. id have to take a look at the turboTA at the junkyard again becuz i think thats how its set up.i think if u do have the fabrication skill, u can use most of that system but by moving things here and there to get it to fit.

 

Yeah i'm pretty good at that stuff, i can weld and I've routed exhaust before, plus when i get all the pipes done i'm gonna have them ceramic coated. I'd have to route the intake tubes anyways cuz I am going to put an intercooler in it.

 

The way that turbo bolts onto that flange it looks like it puts the turbo right where your runners would be anyway. I dont think that it would work for you.

 

Only bit of info I can add here is I do coatings and the HPC coating is nice but only cost $30 to do a turbo housing.


Thanks
Chris@cecoatings.com

 

close but not quite

 

LOL okay how close was i

edit: i also know its not a kit , it came off of the early turbo ta's

 

the turbo and tubo set up on the 81 TTA is actually way different I just didnt want you to think I was flaming you the only thing they have in common are they are both draw through, the one pictured actually appears to be an old rajay/accel turbo systems and they actually make decent power for those with patience to make them run. A guy here in cheyenne had/has one on his el camino with a stock 350 and a 1 leg rear end and it would fry the right tire in a serious billowing smoke show all the way to the finish of the 1/4 mile at street races. It was hilariously good fun. I figured one of those would be really nice when used on a setup like this:

 

Ok I talked to the guy selling this today after work. It is an old accel kit. But I think it will do fine for me because I want to keep my engine stock for the time being. I go to college full time, I can't afford to pay for a big build up right now.

My original question was never answered. Can I get by with a bigger fuel pump and a FMU? Or will I need to get a chip made? The guy said it was set up for 10 pounds of boost. Also my car has a speed density system on it, will I need to change the MAP?

Thanks for all of your help, I will need it in the future. I will keep you posted.

 

a couple POSSIBLE problems i see........

1) Turbo hitting runners.... It doesnt look to me, like it will fit at all!!! You may be getting an lt1 intake as well..... Thanks *** you have speed density

2) Mounting it on passanger side.... i remember when i had my iroc, and i absolutely hated how much room there was on the passanger side!!! Hopefully it will bolt on the drivers side?!?!?!?


3) Id say your car is going to be out of commission for a long time, and I hope you know someone that can burn some dam good chips

 

A little info on the FMU. The FMU is supposed to work in conjunction with your ECM, or in some cases it will replace the ECM completely. Like you said, it will make sure you maintain the correct A/F ratio on boost. The FMU is the single most important part in the correct tuning of a EFI F/I setup. The thing about boost is that you're A/F ratio needs to constantly be calculated as the boost increases. As the air increases, you need more fuel to maintain the correct ratio. You can raise the fuel pressure like you sudgested, but when you might run rich when you're not on boost. The real way to maintain the correct A/F ratio is an external computer module that does all the work in real time. This is the FMU (Fuel Management Unit), sometimes called DFI (Digital Fuel Injection). Tuning a EFI F/I setup is an important part of making the setup reliable and getting all the power you deserve. Its definately something you should look into.

Since you're Speed Density I'll assume you have a 730 ECM. The stock 730 ECM comes with a 1 bar map sensor which will work for N/A motors. It cannot calculate boost, so you cant get a chip made. You'll need something different and here are some options:

You can upgrade your 730 ECM to act as a 749 Syclone/Typhoon ECM by repinning the 730 and burning a custom chip with $58 code. This is the cheapest solution but will require you burn your own custom EPROM's.

You can spend some $$ on a standalone DFI unit. This will be more expensive than the 749 swap, but will make tuning alot easier.

You can find a hardcoded FMU from a supercharger setup. I dont know how well this will work but its an option worth looking into.

You can ditch the EFI and goto Carb. This will probably be the best solution as the turbo kit was designed that way, but it seems you want to stay EFI. Correctly tuning a F/I EFI setup isn't an easy task. But if you put alot of time into learning how to do it yourself you can do it fairly cheaply. Considering the problems with the turbo hitting the TPI, I think you should change your intake setup. Someone mentioned a LT1 intake and that might not be a bad idea.LT1 intake and a 749 swap with a custom chip and you could be making some power. Good luck!!

 

tom what motor is that? it almost looks like one of holley MPFI setups.

 

Before Holley had their system out, there was haltech and the place that casts/casted the manifolds for them were selling them to Force fuel injection. I bought mine from force and used it on my 415 with the stock 85 ECM and an air cap like blower cars use to run the MAF through. A few years and a few cars later I had no ECM but I had the intake setup still. A friend gave me his analog old projection controller when he couldnt get his tuned because he bought another thinking it was the problem. As projection experienced know shortly after that Holley came out with a digital controller and discontinued the analog one. Anyhow I talked at length many times with some of the head Holley techs, and after they assured me in every way that it was impossible, I modified it anyways to work with the Force hardware. On my 355 it ran 11.90's on a 150 shot, drove like a dream and had a beautiful A/F curve on the Dynojet. a year and a half later holley came out with the identical manifold, rails and throttle body (and I mean exactly identical) with the digital controller then the commander 950. Does it have anything to do with me, I'll let you be the judge.

 

when I said the hardware was Identical I meant it. Holley basically used the same intake casting and just added the word "Holley" to them. Unfortunately the casting is flawed because in a hurry to use something that was already available they chose a substandard casting. Bill Mitchell Hardcore Products has been making a 427 crate motor using the Holley EFI system (it is absent from the Bill Mitchell site for some reason), but they-like I, hate the fact that instead of having a cast protrusion to put the spraying end of the injector into (like accel and others do). Instead the casting has an indentation protruding about half to 3/4 of an inch into the top of the port. According to Haltech (when they originally made it), Force (if you ask them today), and Holley (if you ask them too); they will tell you the intake flows in excess of 300 cfm. being that the manifold only fits a 1205 gasket and there are not really alot of 1205 gasket heads that flow near that (leave AFR maybe) it may not really be a problem. I dont like it, either does Bill Mitchell, who has planned on trying some other casting to make his cutomers happy although it may not improve the power. In this photo below you can see my force on the left and the Holley on the right resting on a bill mitchell 427 small block.

 

wow tom, thats amazing. who knew.

but its companies like holley that do that sort of thing, and can get away with it. companies like that know how to make money, take a good idea from somwhere and stamp your name on it.

Best buy likes to do that. yes i work for best buy.

 

you see it alot look at how much jegs puts "jegster"on stuff. ever seen a "jegster" SBC head looks just like a canfield (hint: it is a canfield) or summit putting "pro-line" cranks or rods (cola and detroit power) or "trick flow" rearend girdles (TA), rockers (they're like harland sharp), it is done on all kinds of parts recognized by the famous maker originally.

 

thats it, now im going to buy up a bunch of holley's stuff and put best buy's name on it.

see how they like it.

 

no what your supposed to do is find some parts that everyone could use way cheap and slap your name on it to hide who you got it so cheap from. like proform stuff, or power plus stuff from professional products.

 

Getting back to the fueling concerns, wouldn't a rising rate fuel pressure regulator like the ones made by Cartech solve that problem?
Tony

 

like this?

to fix this problem i got an lt1 intake.

 

guess i dont have a good pic of the turbo hitting the tpi, but the clearance is minimal with the lt1 intake as you can see. i am not going to use the log manifold in the pic on this car, but am going to have custom turbo headers made for my twin sequential setup.

thanks
anthony