Any difference between 89 700r4 in a V6 and 87 in a trans am
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Junior Member
Joined: Jul 2024
Posts: 21
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Car: 1987 Trans Am
Engine: 305 TPI
Transmission: 700R4
Any difference between 89 700r4 in a V6 and 87 in a trans am
Just want to make sure the bell housing is the same before I drop the trans from my 2.8 and start beefing it up for the 350 Im going to build
Joined: Oct 2020
Posts: 1,411
Likes: 676
From: Franklin, KY near Beech Bend Raceway, Corvette Plant and Museum.
Car: 1992 Pontiac Firebird
Engine: 5.0L L03 TBI
Transmission: 700R4
Axle/Gears: 2.73
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
The 2.8/3.1 V6 700R4 trans has the GM Corporate 60 degree V6 bolt pattern bellhousing and the other has the Chevy 4.3 90 degree V6 & SBC/BBC 90 degree V8 bolt pattern bellhousing.
Thread Starter
Junior Member
Joined: Jul 2024
Posts: 21
Likes: 0
Car: 1987 Trans Am
Engine: 305 TPI
Transmission: 700R4
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
Senior Member
Joined: Oct 2021
Posts: 735
Likes: 114
From: Windsor, On
Car: 1984 Trans AM
Engine: 305
Transmission: 700-4r
Axle/Gears: 3.23
Joined: Oct 2020
Posts: 1,411
Likes: 676
From: Franklin, KY near Beech Bend Raceway, Corvette Plant and Museum.
Car: 1992 Pontiac Firebird
Engine: 5.0L L03 TBI
Transmission: 700R4
Axle/Gears: 2.73
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
Yes it means it won't work with a Chevy 350. A Chevy 350 is a 90 degree V8. You will need a 700R4 for a SBC that has a tail housing to mount the torque arm used in a 3rd gen Camaro or Firebird. I guess the tail housing off your 2.8 V6 trans would work. It can't be a 700R4 from a Corvette though as I think the case is different where the tail housing mounts to it. Also don't need the TA mount tail housing if using an aftermarket crossmember that has a TA mount and a aftermarket TA setup that doesn't mount to the transmission tail housing.
Rebuildable cores for a 700R4 transmissions are a dime a dozen. You wouldn't adapt a 60 degree V6 transmission to a 90 degree V8 application when GM made millions of them to fit a 90 degree V8.
Rebuildable cores for a 700R4 transmissions are a dime a dozen. You wouldn't adapt a 60 degree V6 transmission to a 90 degree V8 application when GM made millions of them to fit a 90 degree V8.
Last edited by Airwolfe; Oct 15, 2024 at 02:35 PM. Reason: Grammar and to make better sense.
Joined: Sep 2005
Posts: 27,935
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Car: Yes
Engine: Usually
Transmission: Sometimes
Axle/Gears: Behind me somewhere
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
The 6-cyl transmission is inferior to a V8 one in several ways (valve body calibration, servo, clutch packs, etc.) as well as not bolting up.
Get a V8 one to use for your core and throw the 6-cyl trash in the trash. Or, put it on craigslist or something, there's sure to be somebody who needs one, maybe not right away, but sooner or later.
Get a V8 one to use for your core and throw the 6-cyl trash in the trash. Or, put it on craigslist or something, there's sure to be somebody who needs one, maybe not right away, but sooner or later.
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Joined: Jul 2006
Posts: 2,886
Likes: 797
From: 212 is up in this Bit@#
Car: Resto-Mod 1987 IROC-Z Clone
Engine: Alky fed L92 Vortec Twin-Turbo 6.8L
Transmission: My own built/ design 4L80M
Axle/Gears: Custom 12 bolt (4.10:1)
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
The V6 Torque-Converter will also not Bolt to the Flex-Plate for a Gen-I SBC.
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Joined: Sep 2002
Posts: 253
Likes: 25
From: honolulu
Car: '86MCSS
Engine: 396 .030"
Transmission: M20
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
These are pics of manual transmission bellhousings but you can clearly see the difference in the bolt pattern between a 60* V6 and a 90* V6/SBC...
https://www.thirdgen.org/forums/atta...gsv8vs6cyl.jpg
https://www.thirdgen.org/forums/atta...gsv8vs6cyl.jpg
Joined: Oct 2020
Posts: 1,411
Likes: 676
From: Franklin, KY near Beech Bend Raceway, Corvette Plant and Museum.
Car: 1992 Pontiac Firebird
Engine: 5.0L L03 TBI
Transmission: 700R4
Axle/Gears: 2.73
Re: Any difference between 89 700r4 in a V6 and 87 in a trans am
Where are you located? @Edsiroc just posted he has good working 700-R4 up for grabs for about $300.00 if anyone is interested.
Southern California Area - Any interest in a good working 700r4?
Southern California Area - Any interest in a good working 700r4?
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