will a big block fit?
lik69
03-22-2010, 12:01 PM
does anyone know if a big block will fit inside of an '86 fiero se? i was thinking about putting my LT1 in but i read a forum that said they put a pontiac 450 engine in but i wasnt sure if they came in small blocks or if they were only big blocks. thanks for the help.
MrPbody
03-22-2010, 01:42 PM
The Pontiac is a "Pontiac", not a big block or a small block. Dimensionally, it falls in between the small Chevy and big Chevy.
To make the Pontiac "fit", the transmission was used from a '80 Riviera FWD TH325. The starter was relocated to the passenger's side and the flexplate was "custom" made to use in the smaller bellhousing. The TH425 from the late '60s/early '70s Eldorado and Toronado would be a better choice, IMO.
Installing a BBC would be an exercise in inginuity...
Jim
To make the Pontiac "fit", the transmission was used from a '80 Riviera FWD TH325. The starter was relocated to the passenger's side and the flexplate was "custom" made to use in the smaller bellhousing. The TH425 from the late '60s/early '70s Eldorado and Toronado would be a better choice, IMO.
Installing a BBC would be an exercise in inginuity...
Jim
lik69
03-23-2010, 09:41 AM
thanks thats a pretty big help. but do you know if it would be possible to install a manual instead of the autos?
MrPbody
03-23-2010, 01:25 PM
I know of no manual that will both "fit" AND take the level of power output from a large-displacement engine. Maybe one of the "ZF" trans-axles as found in Pantera, but that would "move" the engine too far forward.
Jim
Jim
big white bufflo
03-25-2010, 07:21 PM
i know they make conversion kits for small block wy not use a stroker 383 that will give you plenty of power and torq
MrPbody
03-26-2010, 09:02 AM
White Buffalo,
The kit provided by "V8 Archie" is the one for the small block. The trans used is the TH125. While a very good transmission behind a 4 cylinder or even a mild V6, behind a V8 it's "days are numbered". Adding more power to a 350 will only compound the problem.
I don't disagree, 383 is probably the BEST of the small blocks, at least for "street use". For "clarity", using the term "stroker" with "383" (when talking Chevys) is "redundant". ALL 383 Chevys are "strokers". (:-
Jim
The kit provided by "V8 Archie" is the one for the small block. The trans used is the TH125. While a very good transmission behind a 4 cylinder or even a mild V6, behind a V8 it's "days are numbered". Adding more power to a 350 will only compound the problem.
I don't disagree, 383 is probably the BEST of the small blocks, at least for "street use". For "clarity", using the term "stroker" with "383" (when talking Chevys) is "redundant". ALL 383 Chevys are "strokers". (:-
Jim
lik69
03-27-2010, 04:20 PM
will a 2m6 transaxle bolt up to the LT1? this guy on another forum said it would but i just want to make sure before i try.
Sunfirepro
03-27-2010, 09:17 PM
there is a 350 kit you can get to make it fit. caddy northstar also fits and should mount up to the original trans carries an amazing excel..
lik69
03-27-2010, 09:35 PM
thank you i'm about to buy me a northstar now because with the LT1 i'd have to get an expensive conversion kit.
MrPbody
03-29-2010, 01:44 PM
Before buying ANYTHING, make SURE the bellhousing pattern is the same. I don't have a Northstar just lying around, but I'm not sure it uses the same type of trans as other GM FWD cars.
Jim
Jim
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