The DR. has some questions. I just recieved a '91 Camaro for FREE. It has TPI, and the engine is shot so I am going to swap the TPI to the vette. I have been doing my homework on the net, but I was curious if any one had any advice or tips from from previous conversions? The car is complete (wire harness, ecm, the works)

Thanks.

DR. Jay

 

Yes, buy the TPIS manfold and get rid of the Tuneport one. It's a lot of work with an OK payoff. Not to put down the system, but it's so much easier to do a LS1 swap and the payoff is huge.
Just my .02.

 

I have done several!!! Do a lot of reading. I have found the aftermarket wiring is much cleaner and easier to install. The thing to remember is that you are setting the TPI as a stand alone setup. The main problem with C3 is the gas tank. The pickup is OK for a carb but not with TPI, it will suck air at 1/4 tank. The 82's have pump in the tank but lack the baffels to stop the fuel from moving away from pump, so no help there. This also happens with outside fuel pump. If you cant live with that you have to drop the tank and pull the bladder out and modifiy it like the guys that run giggle gas do. 91 TPI should be a MAP with VAT setup. You will also need a VSS on the trans. You will need a custom chip with no VAT codes and this is where you can get rid of all the clean air stuff that the stock computer reads. Also MAP does not lend itself to a modified engines. I like MAF setup you can add some nice HP to the motor and it still runs nice. If your state requires inspections then you may have to install the clean air BS that does nothing anyway, but you will still have to get a chip without the VAT. I also like to use the TPIS runner tubes, they make up a lot of the shortfall of TPI (power dropoff after 4800 to 5000 rpm) mine reves to 5800 with no trouble.
I have been very happy with the TPI setups I have done. My gas milage has jumped way up, my 81 C3 went from 10mpg around town to 18 mpg. HWY was always great because of the 3.08 gears and the lockup 350 trans. With the TPI there is a GREAT difference in low end power which is great for around the town driving.

 

What modification to the tank are you talking about? I've never heard of any tank modification for nitrous.

You can always modify an LT1 manifold to work on a distributor engine...

 

I would be more inclined to swap in an LS1, but I don't have one sitting around. The TPI is free. With the TPIS manifold are you talking about buying just the manifold or the whole system they offer?

 

Thanks for the advice I am going to do alot more reading. I have heard of the fuel tank problem. I think I can bypass the VATS, or just use a VATS lock cylinder. My county has emissions laws, but the vette is grandfathered in (25yr rule). I look forward to the challenge. If you have any other advice or tips they would be appreciated.

Thanks again.
DR. Jay

 

Just the manifold. You can use all the other parts in your kit. I think some one out there is also modifing LT1 intake to fit TPI parts.

 

See http://forums.corvetteforum.com/show...tpi&forum_id=3

In a 78 you can use the stock fuel tank with an 82 sending unit. Fuel system is not that big a deal. I love both my TPI vehicles.

 

Its a good swap youll love the torque it makes,im pulling mine backout for a ls1 swap next week.

 

What vehicles do you have TPI on? I sure would like to know for certain whether I am going to have to worry about sucking air below 1/4 tank after I do my conversion on my 81?

 

ive run mine down as low as 2 gallons and didnt have a problem,but i recently switched to a walbro 255 pump and now on hard jumps off the line on a low tank 1/4 or so itll run dry.

 

 

Ok where might I be able to find a source for the emissions deleted prom?
What is the difference detween the '78-'82 sending units?
Is it length, or is it that it has the extra wires' or both?
Thanks again for all the help. Now I just need to pull the TPI & harness, ECM off the donor car.

Thank's again.
DR. Jay

 

Jims Performance has a nice write-up on the Internet about GM TPI's, including VATS delete, fuel pumps, conversions, etc. Here is the link.

http://www.jimsperformance.com/portinj.html


Here's what he did to my ZZ4...

 

Jims a good guy,he helped my brother out for years when he was running tpi motors.

 

Patsnitrovette - did you have an intank pump? and if so was it a stock TPI pump? Did you use a 82' pickup?

 

since mine is a 73 my sending unit is on the bottom of the tank,the first time i mounted the fuel pump right onto that,worked great,but i wanted something better so i got a 89 truck sending unit and cut a hole in the top of my tank and put a walbro 255 fuel pump on that sending unit so it sat at the very bottom of tank towards the front lowest point.The first fuel pump was a stock tpi replacement.NOw that im doing a ls1 im removing the tank and putting baffles in it ,since its gone to be making alot more power i know itll run dry getting on it hard.

 

Patsnitrovette - How did you mount the tpi pump? Did you just cut off the pickup tube a bit flare it and run a hose between the pump and pickup? Just trying to figure out if I can do this on my 81' pickup. Did you run High pressure rubber lines from the pickup to steel line? Appreciate the help as plumbing is the big challenge I face.

 

It's me again. I guess it is ok to run high pressure fuel hose in a 60psi tpi system as long as the connections are good? Not for the whole system but for certain areas? Just want to make sure I plum this right. I don't want to have to go back and fix my mistakes. I sure don't want to be leaking especially at 60psi.

 

i sent you a private message