Curious if I can fit a big block Chevy in my '87 Trans Am. I've heard "It
won't fit", "It'll fit but you have to shoehorn it in even after blistering
the firewall", and, "Sure, it'll fit just fine! No problem."
Anybody have firsthand knowledge?
What are the challenges or difficulties?
How about swapping in a heavy duty, automatic transmission?
Yes, you can do it. I've seen it done. Hooker even makes headers for 3rd gen
big block swaps. For the transmission you'll need to get a new torque arm
that mounts to the crossmember instead of the transmission tailshaft.
B&M used to make (they still might) a Three Speed automatic torque arm
bracket for 82-92 cars. A short output TH400 should work with the bracket.
As for big blocking a 82 to 92, It has been done. Easiest way, set a
bare block in place with motor mounts. Mark the mount locations, do your
mounts, figure out your oil pan, then set your heads on, figure out
heads vs manifolds, steering shaft, ect.
I put a Pontiac 455 into an '84 Trans Am. It sat right down on the
factory engine mounts. B&M makes an adapter to fit the torque arm to a
TH350 or TH400, but why not build a strong TH700R4 and have an
James Drinkwater wrote:
"Pontiacs" are NOT small blocks. Small block generally refers to a Chevrolet
engine.The Pontiac V8 design differs from other manufacturer's designs in
that the external dimensions of each engine, from 326 - 455 in.
displacement, is identical. The displacement is determined internally with
changes to the bore and stroke; therefore, there is no "big block" Pontiac
engine. Pontiacs are larger than a "small block" and smaller than a "big
block". However, Late model Pontiac automobiles did use the "Chevrolet small
block" instead of a true Pontiac engine. Does anybody in here remember when
this happened ? I bet there are a few true blue Pontiac guys in here !
1976 was the last year for the 455 engine, the Olds 403 became an option in
'77. 1979 was the last year to get the 400 cubic inch Pontiac motors, which
were left over from 1978 production. The Olds 403 was also available up to
In '80 and '81 you could get the Pontiac 301, but If I am not mistaken, that
was the last year for the pontiac motors. I think Chevy motors were
installed in the 3rd gen. cars starting in '82.
3rd Gen V6's 2.8 V6 then 3.1 V6. 1989 only, Trans Am Only 3.8 Turbo.
3rd Gen V8's. Chevy 305 from 1982 to 1984 only V8. 1985 to 1992 Chevy
305 and Chevy 350.
The 4 cylinder 3rd gens were 2.5 I-4's. Same as a S-10.
The Olds 307 was used in B&G bodies until 1987.
The third gen cars did have Pontiac blocks in them... As long as you
ordered your car with the 151ci Iron Duke under the hood. Just a
little levity for I can see some engine discussion wars starting.
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