[markzepp820]

hello, i'm currently doing an engine swap. I have a chevy truck with a 350 that i blew up and i'm wanting to swap it out with a 305 83' firebird engine i have. I just wanted to make sure i needed a bellhousing adapter for this swap. I wasn't sure if a 75' chevy th350 would bolt up to a 80's pontiac engine. So will i need an adapter for this swap?

thanks,
Mark

[richard stewart 3rd]

Hi,
O,B,P, & C, all have the same bellhousing bolt pattern, Chevy has it's own, some bellhousings are drilled with both patterns.
Rich

[WDCreech]

Pontiac stopped using thier own engines, altogether, in 1981. The 305 is NOT a Pontiac!

[jimfulco]

Originally Posted by WDCreech

Pontiac stopped using thier own engines, altogether, in 1981. The 305 is NOT a Pontiac!

It is, however, a Chevy, and if you use the flex-plate and starter from the truck, the 305 should be an easy bolt-in with no adapter needed.

I'd use the intake system and distributor from the truck, too, since they aren't computer-controlled like the 'bird motor was.

[markzepp820]

thanks guys... The engine i have that i want to drop in my chevy truck, I'm pretty sure is a 1983 Pontiac Firebird engine. I looked up the engine block ID# and head casting#'s and it is a firebird motor. Its the LU5 5.0 with crossfire fuel-injection and 58cc heads. Whats wierd though....is when i got it, it had an aluminum intake a Q-jet carb on it. The guy told me it came out of a 1978 chevy van.... the past owner must of made some changes to it before he put it in a van. I just wanted to make sure i did or didn't need an adapter plate before i swapped.... So i still don't need an adapter...right???

thanks much

[markzepp820]

okay....i just looked up some info on the firebirds. So, they started putting chevy engines in pontiac cars after 1981? thanks

[fast68]

howdy there

well 82-up all firebird were chevy powered

'81 was the end of the pontiac v8 in the F bodies

all '82-85 were all chevy 305 in the v-8 cars, even for police package.

'86-92 were chevy 305 or 350 in the v-8 cars,

see this page for list and specs of drivetrains in these cars:
http://www.thirdgen.org/tech-data


pontiac did not have a 305


they had the 301

you are confusing things badly it seems.

and an adapter is not what you would need anyways.

you would need the right tranny for the swap if you were putting a BOP division engine on a chevy only trans. or vice versa as well.

some trannies were both bolt patterns, 10 bolt pattern universal, from factory and were common on th350 and 2004r

i have one of each right now

buick division built

one 2004r in the 85 el camino 305 chevy


and a th350-c from an 81 chevy pickup 350 oldsmobile diesel


these fit all gm v-8 engines and L-6 and V-6 cyl 90 degree bolt pattern also, and also the ld 2.5L iron duke 4 cyl engines, and all the old gmc big v-6 truck engines of the 1960's years

and most gm diesels too

heres my 1981 chevy truck oldsmobile diesel 350/TH350-C universal 10 bolt pattern buick built bellhousing:


i keep it in the basement because its a good tranny and all i need to run it in the future is a gasoline engine th350c torque converter in which is about 100 bucks online. ill use it in some vehicle some day.
most likely the 78 c-10 maybe if i decide to not run the 3L80HD anymore for some reason.

see this thread:

200R4 vs 350 Turbo

and this one:
Transmission Information.

[markzepp820]

alright....thanks fast68