I have a few ?s and i have looked but i havn't found many of my answers... 1. what are some things that will have to be changed? 2. Will the tbi computer plug into the car or will the wires need to be modified since it had the tpi computer in it. 3. will the tpi fuel pump work for the tbi? Thats about all i can think of right now. thanks everyone in advanced. -Matt

 

Your TPI fuel pump is a great choice when running TBI; if it works good, then keep it.

I think you will have to move a few wires to make the harness properly plug into your TBI computer. I would get the wiring diagram for both engines and then move the wires appropriately. I think around here the term is ,"re-pinning" the harness.

If you are running 1986 cylinder heads the TBI intake won't bolt on easily. You have to modify the angle of the middle bolt holes because 87 and up engines changed the design. You can also use an older carb intake for your TBI and use a carb adapter plate to bolt on your TBI.

Your factory TPI cam is better than the TBI, as are the exhaust manifolds. Keep them.

You will also need new throttle cable, cc cable, and you probably should switch to the small cap HEI distributor. You can re-wire your current 7 pin module big cap HEI to run with it, but you also need a wiring diagram to make that right as well.

Why are you ditching your MAF TPI?

 

im considering just buying a 89 Rs tbi engine thats why i asked. I just want a more simple engine to work on and my old silverado has a 350 tbi and it ran great and was very dependable yet easy to work on. the tpi ran good but the fuel pressure reg went out and when i replaced it the car seems to just miss and struggle running. so before i spend the $ getting the tpi back together id rather go ahead and get the swap done with.

 

I would replace the fuel pump before I do anything else. If your regulator went bad, why was that? What was it doing?

Normally the symptoms you describe are either a clogged fuel filter or a fuel pump that's on it's way out.

I like this pump:

http://www.partsamerica.com/ProductD...ype=52&PTSet=A

After you do that, I have a feeling that your problems will go away. Don't forget a new filter!

TPI is not any more difficult to deal with than TBI, different but no more difficult.

Good luck!

 

we changed the filter and the car wouldn't start at all but when we would relieve the pressure in the fuel rail the car would try to start but after a few times the car would "flood" again and wouldn't even try to start. also i need to get another cooling fan due to mine is out of a 1989 cavalier... dont really see how that works. i was going to just swap intakes but then i found a complete motor in another car for $300 so im gonna check it out and see what i find out... i believe it has around either 131,XXX miles

 

I'd spend a little more time getting your system running. Pull and clean (or replace) your plugs since you have been flooding.

Another huge problem with cars like yours is the Mass Air Flow sensor. Try smacking it around a bit while you're trying to start. I have seen that happen more than once when they go out.

Anyway, your system is good and once you fix it, you'll be happy. Don't give up!

 

I just dont like all the sensors because the MAF sensor is like what $250? heck i dont know i have never looked. I just want a simpler engine that still has the same power or close that the TPI has so that the car seems the same even though i have never drove it before anyways, I just want an engine that i can make look good and be easy to work on. Just to get the camaro going and running great would be awesome but after my first camaro FI and all the issues i had with it i was going to put a 305 carbed in it but i sold the car and got the truck. The truck is the one with the 350 tbi and it sounds good and runs good i really just want the car to be that way. are tbis really that bad? i mean they have a decent performance wouldn't you say?

 

The mass air flow sensor is about 175 with a lifetime warranty. That depends on if you will keep the car forever. If yes, buy it and then if it goes out again you'll get it replaced.

I love TBI, don't get me wrong about that. I just think that if you are starting with your system it will be easier to fix it right and then forget about it than it will be to put TBI on it. TBI is still full of sensors and requires the same types of troubleshooting that your TPI does. It is not any simpler of a system in how it works. Just different.

Your engine has all the same advantages as TBI over a carburetor so I just wouldn't ditch it. You need the same meters and tools to diagnose problems on either setup. It will take a long time to sort out the wiring and what not to change over to TBI with no real advantage.

 

tell ya what, when you "simplify" your car and get rid of all that stuff. I'll take that garbage off your hands. I really so no good at all coming out of spending money to put a tbi 305 in place of a tpi 305. Dont waste your money.

 

I have such a hack job of wires that are cut and lead no where, i have relays that have no place to hook up. I have tried to scan my computer but im guessing the my wires are so hacked up that the module can read my error codes. I have tried the ingnition to get the check engine light to flash and give an idea of the code but that failed. When we started it last the engine had a light knock im guessing from where if was having bad oil flow because the car what shaking badly and the car wouldn't run with out me giving it gas... just a serious pain

Best part about this "garbage" is that it has a nice value so to take this garbage it will cost.

 

You would be better off getting a wirin diagram and fixing your harness or replacing your harness with a used one. You could use one from a 1986/87/88/89 TPI car and still re-use your ECM and related hardware.

If you're gonna ditch everything, you might as well go carb with the old vacuum advance HEI. And like stated above, sell the TPI system complete here in the classifieds!

 

tell ya the truth i was gonna go carbed but my dad thinks i should go tbi for some fuel economy of fuel injected along with easier to start. If i do swap then i am going to sell the TPI to help pay for the swap. Also im not sure if the tbi engine is stock or modded but i might also do some upgrades myself. Not alot but just enough to get some performance and still have gas milage in the double digits lol im not trying to seen like an A** tho im just trying to figure out what to do and how hard it is to do it. thanks for helpingme so far tho. -Matt

 

In all honesty, the best thing you can do is to figure out your current problems and fix them. You don't have a full grasp yet of how fuel injection works or you wouldn't be talking about a TBI swap. Fixing your system will train you in the fine arts of EFI and make you a much more capable troubleshooter.

You have a good, solid foundation to start with. Take it from the top; start with compression check. Then check ignition system and firing from the coil and distributor to the plugs, then check fuel. You should get yourself a Chilton's total car care manual, a fuel pressure gauge, and a multi meter. You will need these things for TBI as well, so it's not a loss.

Fix that car!

And then let us know your results. You should start a new thread in the Tech, general engine forum and start your question with, "My 86 TPI IROC won't start, what do I do?"

Things will take off from there. There is a treasured wealth of knowledge here just waiting to be tapped! (and you'll have awesome fuel mileage as well!)

 

i dont have much money to work with and i have tried to get error codes but the scanners cant link to my computer so i dont know whats up with it. I need to get electric fans and many other things that have screwed up but with this other engine id have a pulley fan so thats solved. need to work on fuel system then i could just take off the carb and go from there instead of half the engine. im going to school for auto body and collision repair so cars are my life but i still want an easy motor to work on and have fun with.

 

well been talking to my dad about everything.. keep in mind im 17 going on 18. We are just going to see about fixing the TPI and if that fails that we will just get another intake and carb and swap it out. This way we at least tried but heres a ? can i use a pulley fan on tpi?

 

You can, but you'll need to get a different radiator shroud. By the time you get it all set up, you'll have spent more than just getting another electric fan.

 

Yeah, if you need to until you get everything sorted out, you can run a separate relay and switch for the fan so that you can just turn it on when you need to.

Put it on your list of things to fix!

Good luck!

 

thanks man, appreciate all the help.. hope i dont look like a total a**. Just thought i could make life easier by avoiding a prob. oh well i look forward to the old tpi roar again!

 

You're doing fine.

Remember, Chilton's total car care manual, digital multimeter, and fuel pressure gauge. Get a compression check gauge set if you don't already have one.

Start at the beginning.

 

thanks alot man you saved my tpi

 

Did you get it running already?

 

no not yet but as of yesturday the tpi was gonna be gone now i feel like getting it going again.

 

good deal. that was my whole point in posting, really, not just to get ahold of those parts, lol. TBI would cost too much cash to make it work the drop in stock performance. You'll get it goin.

 

Thanks for the support man hopeing no hard feelings. later man -Matt