79 trans am overdrive
6669charger
07-22-2008, 11:46 AM
Is there a transmission that will bolt to the back of a 403 that has overdrive?
mikeemon
07-22-2008, 12:51 PM
The only auto tranmissions with BOP bolt pattern that I am aware of are TH350 & TH400. Others could be used with bellhousing adaptor. You will most likely need new crossmember, they are out there for some conversions, an electric brain and driveshaft modifications. I would like to do the same with my, 'bird, but have not worked out all the details yet.
MrPbody
07-22-2008, 01:21 PM
6669,
Yes. TH200-4R. It will generally bolt right in where TH350 was. If the 403 isn't pumped up TOO far, it will live well behind it. Level 10 (brand name) builds one they CLAIM will live behind high-horsepower engines, but our experience is that their "version" of "high horsepower" is in the 500 range and a small block, so torque output is minimal. They DO NOT "live" behind a 455 Pontiac with all the goodies.
A company called "Shiftworks" makes a conversion kit for the shifter, too.
Jim
Yes. TH200-4R. It will generally bolt right in where TH350 was. If the 403 isn't pumped up TOO far, it will live well behind it. Level 10 (brand name) builds one they CLAIM will live behind high-horsepower engines, but our experience is that their "version" of "high horsepower" is in the 500 range and a small block, so torque output is minimal. They DO NOT "live" behind a 455 Pontiac with all the goodies.
A company called "Shiftworks" makes a conversion kit for the shifter, too.
Jim
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