I did some searching, and found out that there are some variations in chevy TPI setups. A friend of mine just totalled his 89 IROC 'vert this morning... Hit some ice, went off the road into a couple of maple trees. Broke his leg, wrist, and got some bangs and bruises, but he is ok. Anyway, his Dad said it has a 305 in it, but I could have swore that IROC's had 350's? Will this TPI setup bolt onto my old school heads, or no? I really want to use this setup, as I can get it cheap. What would I need to do to make this whole deal work? My heads aren't really old school, they are WP Sportsman II's. Thanks for any help you guys can muster up!

IROC cars had both 305 and 350TPI, with the majority of TPI cars being a 305 "LB9?" i think that was the option code, anyway, its the HO 305. The 350 cars also had TPI but the bigger engine was just less common whether TPI or MPFI.

I'm pretty sure the TPI intake will bolt up to the heads, but you might have to open up the bolt holes in the middle (on intake, not on head) so you can get the bolts in. I have a performer intake designed for the TPI heads, we hit it with a drill bit and it now sits on a set of 1970 307 heads, no problem.

Just mock it up on the heads and you'll see which holes you have to open up.

*EDIT*, the runners and intake on the 305 and 350 cars are the SAME, no diff, the system was designed for the 305 and just dropped onto 350s as well.

the tpi setup dies at 5000rpm on a stock 350 so if you plan on running any kind of cam don't use a stock tpi setup, they're great torque producers but act like a rev limiter on 350. fbody.com will get you a lot more info on them but the first engine mod i will make on my 88 350 iroc is to pull the stock intake and runners and replace with bigger pieces, my son did on his 91 350 iroc and you wouldn't believe the difference.

So if the Camaro TPI is no good, then what else could I use? Is the Vette TPI different than the camaro? Keep in mind I'm not talking about the setups computer wise, I will not be using a stock computer. This will be for a turbo charged application.

it's not that it's no good, it's just for stock low rpm motors. all the major manufacturs make hi rpm fuel injection units now but they cost. if you have a four by four the tpi would be a great setup for wheeling up and down the hills for no stalling performance. or buy it and put it on ebay for a nice profit besure you get all of it, the harness, computer, sensors, distributor, runners, manifold, and throttle set up. if you want to use it, all you need is a new manifold and runners and maybe a throttle body to match your engine and just sell those old pieces on ebay.

Is there any difference between the Camaro TPI setup, and the Corvette TPI setup?

Same exact set up. Difference in Vette engines is almost always the exhaust system.

The Vette setup will fit the older style heads without any modification. The Vettes used the same aluminum heads that you would find on a ZZ4 crate engine (older style bolt pattern). This is the only important difference between the Vette and Camaro/Firebird setups. I believe the EGR positions may be the only other difference, but you probably won't be using that anyway.

Check out Street and Performance (http://www.hotrodlane.cc) and go to their TPI page. That should help answer most of your questions. Shoot me an email if you'd like, I'm in the middle of a TPI swap at the moment.

Ryan

The difference from 305 to 350, other than chip calibration, is the injectors have a higher flow rating on the 350. 89 is MAF, and is harder to plumb because of the MAF sensor. The intake has the revised 87 up center intake bolts, but they can be elongated. TPI is great for a mild 350, but like said above, falls flat after 5K RPM. With that said, if you can get it cheap, you could always get the Holley Stealthram intake and rails, and use the TPI parts with it for a nice EFI setup.

If you're really considering this, try to get the whole car. The swap I did on my 88 nickel and dimed me, and I was going from TBI to TPI.

If the motor is out of a convertible, it is definitely a 305. The injectors flow 19 lbs/hr compared to 23 lbs/hr for the 350 injectors. Center two bolt holes on each side of the intake will need to be elongated. I had an 88 IROC-Z with a 5.7 motor that ran 13.9 on street tires with 2.77 gears. I ported the factory base manifold, added large tube runners, ported the upper manifold, put in a ZZ-3 cam, Edelbrock TES headers, and a Flowmaster Cat -back exhaust. It also had the factory Cat installed. The car got 22 miles per gallon and still passed MA emissions! I tossed a NOS System on it and knocked off a full second with some sticky tires once I got sick of the high 13's. You can make them go pretty good with the right parts thrown at it. The 89 car has the V.A.T.S. ignition system with the specially-coded ignition key for security purposes. You will have to get a new wiring harness from Painless Wiring to get rid of the VATS, because you won't be able to integrate it into your car. You will have to change the computer to an 87 or 88, also. It will cost a pretty penny by the time you are finished,

All IROC/Z28 convertables came with a 305, only the Hard tops/t-tops came with 350s. If you really want the motor and want more then "ok" performance, then as stated above, your best bet is tossing the whole tpi system. I'd recommned going with TPIS' Mini-ram system along with one of their ZZ-series cams, etc., or going with an (I believe it's Accel) Super Ram with a TPIS Big Mouth lower intake, or maybe with something from SLP. Personally, I don't really care for GM's "hot cam" and would rather go with a ZZ-series cam, but that's up to you and what you plan on doing with the motor/combo. Are you planning on putting it in your Chevelle or another car?

This is going on my Chevelle. I didn't want to spend a ton of money on the TPIS stuff though. I'm pondering a twin turbo project, and I don't want to mess with modding a carb to work with a turbo system.

Originally posted by RacnJsn95:
This is going on my Chevelle. I didn't want to spend a ton of money on the TPIS stuff though. I'm pondering a twin turbo project, and I don't want to mess with modding a carb to work with a turbo system. Cheap and twin turbo turbo should never be used in the same sentence. Most of the good stock turbos that will work for a 350 are getting very hard to find and expensive when you do. 90% of the T3's for sale out there are just too darn small. You can run some of the diesel holsets or other deisel turbos, but you will still need to purchase external wstegates as the internal ones are not big enough. Also most of those don't produce very good numbers at low boost numbers, but really sing in the 15-30 psi range. You will need to build the motor approriatly.

Add in the other costs like fabbing, headers, intercooler, etc. it is far from cheap. If you wanted to go turbo you would probably be better off to look into a single set. A HX35 holset turbo from a Cummins will generally make a nice spooling 400 hp small block. If you run a stock TPI manifold I would definetly upgrade runners and do some porting to the upper throttle body area. Then it should be a decent street setup with boost.

If you are going to Turbo the car, then you are now talking big $$$. You will need much larger injectors, probably a better (aftermarket) computer to drive those injectors, a hardcore fuel delivery system, larger throttle body and MAF sensor, etc. The factory TPI setup is going to choke a motor with a twin-turbo setup, even with the larger tube runners and factory ported base manifold. Go with a TPIS mini-ram for the most HP and a stick or a Super Ram for torque with an automatic. There is really no way around it if you really want to make some power with turbos. Either Holley or Accel has a tunnel-ram style intake that takes the place of the TPI manifold and runners that you can just throw all the fuel rails, injectors, and sensors on from the TPI setup that is pretty cheap compared to the Mini-ram or the Super Ram. Look in Jeg's or Summit.

I haven't seen anybody post it directly ... NO an '89 TPI will not fit pre-'85 heads.

Now there may be some machining or adaptors to make it work, but it won't without some sort of work.

Neal

I know this won't be a cheap project, or one that will get done quickly... I am a certified welder, and we have a tubing bender, so I plan on fabbing up all my own stuff. For the "up-town" computer system I plan on running a MegaSquirt system. I already have one brand new T4, and I am slowly looking into getting another one as funds allow. So if I want fuel injection my best bet would be to get an aftermarket setup, and not a factory one.

Originally posted by RacnJsn95:
So if I want fuel injection my best bet would be to get an aftermarket setup, and not a factory one. You got it! ;) graemlins/thumbsup.gif

Hey Jason was the vert an Auto or a 5 speed? BTW None of the verts had 350's. Email me off line if they are going to part it out.

BBK is coming out with a $399 TPI intake in a month or so. You may want to watch for it, as it may be an alternative to the TPIS Miniram or Holley Stealth Ram.

Novadude has a point. The biggest flow restriction is the factory base manifold. I ported mine too much and had to get it Tig welded to fix the hole. My car was pusing about 300 HP on the motor with stock heads. The aftermarket bases raise the base of the manifold up and have a different approach angle to get a better shot at the back of the intake valves. The factory base is almost completely flat on the inside of the runners with a shallow angle.

Now see, I can swing $399! But I just wasn't going to kick down $1200 for something from TPIS!

Sorry for the double post, but I just wanted to show you guys a picture of the wrecked car...

http://img.photobucket.com/albums/v102/yukonharry/MVC-001S.jpg

The driver was lucky to be alive! I've decided to pass on anything coming from that car now...

What's the buy back price from the insurance co?

I don't know. Do you want me to ask?

I was just curious what the insurance co thought it was worth.

i do alot of third gens, if i was gonna do anything id say go with an LT1 manifold setup
IM me at dragracer6900 for more info

Jeff- I don't know what the buy back is, and neither do they at this point, but the insurance co. is going to give them $3100 for the car. They paid $4500 for it just a month of so prior to that...

Brute- What's this about an LT1 intake setup?

Jsn,

Go here for the LT-1 retro-fit deal:

http://www.lt1intake.com/services.htm

However, before you dump the long-tube-runner TPI idea, how fast do you want to go and how much are you gonna drag race your car? For a predominately street-driven car, the torque of the stock TPI is hard to beat and would be especially nice in a heavy Chevelle.