I just bought a bit of a project car and it came with an LO3 and no transmission (although it was a stick) and the engine was pulled out of it. Now in order to put this car back together I need a tranny and some misc engine and interior parts, but thats aside from the point. I was hoping to stroke it to a 383 and convert it to TPI. Now I know that a lot of the small block stuff is the same between 305 to 350 and 383 but what kind of electronics do i need to start looking for? or more importantly what will be the same? Now I'm hopin to get mid 300's HP and TQ on a N/A setup. Is that feasible with only a couple minor mods like a cam and headers?

If you guys need any more info just ask. I'm sure there's some vital information missing somewhere.

Electronics wise, you will need to get a used wire harness and ecm from the same or very close year car. They switched from maf to map in 90 IIRC.

Knock sensors are different
knock sensor module is different
computer proms will need to changed or highly recommend custom burned.
Your injectors are different.


As for physically bolting. Just watch out on the two middle bolt holes with the heads you have. Some the 2 holes go strait down, some all 6 holes go at same angle.

IIRC, 350/383, cam, stock L98 heads, headers should get you around 300. A stock L98 was 245 at the fly.

Ok, now i feel like an idiot but i got to lookin at this motor an i find out that hey theres a mechanical fuel pump on the side! so i looked some more and see that theres a quadrajet under that air cleaner. sorry for the wrong info. im still lookin to make it a tuned port but ill need a lot more stuff wont i? It is that a CCcarb setup in 85 right? will any of that stuff work?

I know ill need to drop the tank and put in a new fuel pump. but are the electrical lines for pump feed there or do i have to run them? Are the senders the same? I'm pretty sure ill have to run a new fuel line cuz CCcarb goes to the wrong side of the car with its pressure line and it might not even have a return line (not sure havent looked under the car yet).

Oh and thanks for the info Dale I think I'm gonna hafta start lookin for some L98 heads. I have a quick question about the block, Do i need to worry about exceeding the horsepower limits at 300 or even 350? I have a 350 with 4 bolt mains in the garage from an old chevy truck that i dont wanna use unless i have to. I'm planning on keepin mine relatively stock for quite a while.

Don't take this the wrong way, but, your absolutely crazy! If I had my hands on an LG4 w/5-Speed, oh my goodness, what I would do to it (and I'm referring to keeping the carbureted system). Putting miles per gallon aside, the advantages of running a carb over the stock TPI system are very substantial. Stick with the carb, and it doesn't have to be a computer controlled carburetor. There's no reason to switch to TPI, unless it actually was TBI from the start (no offense, TBI guys)....

I dont know much about carbs, infact I didnt even touch one tell last summer, and that was in a boat. Didnt have good luck either. So what is/isnt in a carb thirdgen, Id be lost!

If your going to build a motor from "nothing" and with your car. Id get a decent block, have it worked over, put some vortec heads on it, marine vortec intake, stay with a 700-750 carb, cam for style of intended use.

But thats me because I am learning right now swapping wire harness crap around is not the funnest thing in the world. Swapping gas tanks in a 3rd gen isnt a picnic either.

I remember how the only and last carbed car I had ran. It didn't. It didn't run good in the cold (I live in Ohio so it gets cold a lot) Plus im not going to take it easy on this motor so id like to get gas mileage above single digits.

Ok so i got another question... Whats the difference between a TPI wiring harness as compared to a stick-shift harness. are all the wires and sensors the same or do i have to find one from a 5-speed?

A TPI harness from an automatic car will work just fine with a 5 speed manual. It's the other way around where you end up missing a few things. An original 5 speed harness doesn't have the torque converter lockup wiring that's needed to run an automatic trans. So if you're keeping a 5 speed trans, you can use either a standard or automatic TPI harness.

thank you so much, thats AWESOME news!
Ok so now i have another couple questions...

Is there any difference between an engine wiring harness for a firebird to a camaro?
Are L98 heads the same as LB9 heads?
Is there any reason NOT to get aluminum heads? (aside from price )