carb to tpi questions regarding my situation
 

Hi everyone, I have a 85 trans am, the previous owner swapped out the original 305 for a 355 sbc, in doing so he removed all emission devices, I live in Ontario Canada, although the car doesn't need an annual emission test it apparently needs to be emission compliant with all devices installed and working condition. Although some say that is not true for hot rods, at this point idk and will be swapping to a 350 tpi which I have ready to go from a donor car(89 gta) I bought when restoring the car for some interior parts, now before I pull out the sbc and put in the tpi I was wondering how I could get the tpi system to fit ontop the 355 that's in the car now, these are the questions I have

1. I know the tpi intake manifold won't fit on the cylinderheads, would buying a aftermarket tpi manifold like the eddlebroke hi flow eliminate this problem?

2. Do I really need to get the computer tuned? The previous owner gave me the details on whats in the engine, how true idk,
(modified 355ci gen 1 Small block World product specs built 430hp, 4 bolts main, World combo heads/intake Sportsman 2 heads, Holley 750 carb , Holley stub stack, Kool blue performance air filter, Wo forged internal, Eagle I beam rods, flat top pistons, reground crankshaft, Comp cam xstream 284 cam, Hedman headers, custon 3" free-flow exaust , Imco racing catback, MSD streetfire HEI ignition etc.)

3. Since the car was a 305 can i get away with installing a new fuel pump in the tank or do I need to swap the tank out aswell?

Re: carb to tpi questions regarding my situation
 

1. Why won't they fit TPI? Are the ports too large on the heads?


2.Yes. That's a giant cam for a tpi. NOT a good match. It'll probably barely run with a tune and it'll be choked beyond belief.


3.We don't know what pump is in the tank or if it has one there since things have been changed around substantially. For tpi to work WITH a motor it's a match with you'll need a tpi sending unit and pump. Even port injected V6 units will work. Any factory tank will fit the sending unit.

Re: carb to tpi questions regarding my situation
 

1. Tpi won't fit because I read on the fourm that the 86-91 tpi intake manifolds have some sort of centre bolt holes at a different angle that won't fit gen1 cylinder heads? Maybe I misunderstood?

2. So what kind of a cam do you think I could get in there should I just use the original cam from the tpi 350 motor I have?

3. Makes sense ill just swap ot the tank I have a new bosch fuel pump lying around anyways lol. Plus I gotta do all the return lines and install the emission canister so might as well do it all at the same time

Re: carb to tpi questions regarding my situation
 

Dude you are in for a world of headache... Its hard enough to swap over to TPI and make it work with a stockish engine much less one such as yours. Hope you have good patience and are an excellent mechanic..

1. 85-86 fbody tpi base plates will have the earlier angle bolt holes. But later ones can elongated to work with earlier heads as well.

2. Use the original cam. If you want to upgrade, comp 8-501-8 is the biggest on a factory manifold.

My suggestion would be to use the whole original tpi 350 if you have it. Make it easier on yourself.

Re: carb to tpi questions regarding my situation
 

Your right just going to swap in the 350 the way it is, I just want to enjoy my trans am, the engine in there is a monster, it's fun, yes goes fast, but controlling that much power is more work then play, plus the stress of getting booked for not having emission equipment is torture when driving around.

Thanks for the info maybe later on I'll do the vortec build with a hi Flow manifold, for now I gotta get the engine in. lol this is going to be a huge headache, at least the tpi is out of the donor car.

Oh one last off topic question, how do I disconnect the mechanical speedometer from the dash of the 85 i tried once before and I gave up there was no space to get at anything from behind? I know it has to come out for sure this time when doing the wiring lol.

Re: carb to tpi questions regarding my situation
 

Lol patience no almost none, but that's what smoking and swearing are for lol, I would say I'm a good mechanic but with everything there is always so much more to learn, the thing I hate the most is when a bolt won't come off, or breaks trying to get it off or when you over tighten lol, I usually break them when putting back on tho lol I really need to get a torque wrwrench, but I never feel like it's tight enough still.

Re: carb to tpi questions regarding my situation
 

Couldn't tell you the last time I had a cable driven speedo out, had to look it up. https://www.thirdgen.org/forums/faq-...-fix-pics.html Post #1 explains how.