[slider in wa]

The "C.O.E." runs a 455 Olds in front of a 400 auto. I don`t think the Olds and Chev Bell housing are the same bolt pattern. Can anyone confirm that for me? I am thinking of running a Gear vendors overdrive unit , but need to know if the tail shaft for an Olds 400 auto is the same as the Chev? Ultimatly i want to change the engine over to a 383 Chev motor, with 400 auto and G.V. overdrive.So i need to find out if the 400 trans is the same for Chev and Olds. Please advise me if you can, and thank you in advance.
Slider in Wa.

[M&M CUSTOM]

The BOP and chevy bellhousings are NOT the same bolt pattern.
The easiest way to tell is look at the locating dowel pin holes, the two bolt holes above these match the two below in width for the chevy pattern.
The two above are closer to each other for the BOP pattern.
The two top holes are located lower toward the crank centerline on the BOP than on the chevy.
http://hotrodders.com/cgibin/album/a...ns_adapter.jpg

[ April 28, 2003: Message edited by: M&M CUSTOM ]</p>

[slider in wa]

O.K. , And thank you. But can you tell me if the tail shafts are interchangable? If they are i could swap the Gear venders overdirve to the chev engine later. Any thoughts?
Slider in Wa.

[M&M CUSTOM]

Oh yeah, I was so tired when I got home from work this morning I forogt to tell you.
The cases are the only difference between the chevy and the BOP transmissions.
There are however four tailshaft housings for each the TH-350, and TH-400.
The 350 housings are: none (four wheel drive), 6 inch, 9 inch, and 12 inch.

The 400 housings are: none (four wheel drive), 4 inch, 9 inch, and 13 inch.
This info and more can be found here: http://www.tciauto.com/tech_info/trans_dims.htm

[ April 28, 2003: Message edited by: M&M CUSTOM ]</p>

[slider in wa]

Thanks M&M!!!! That`s a good site to add to my favorites. So if i got it right., i should be able to use the same "GV" unit on the Olds tranny now and the Chev tranny later. They cost about $2,400.00 So i need to get it right.At 22% over, i think it will be a good investment. I did read , when i was studing up , that if you change to a different vechicle , you can exchange your existing "GV" unit for the right one plus some bucks. Thanks again.
Slider in Wa.