WPO301 1963-1964 Pontiac V8 to 1997 and Older (SBC style) Chevy V8 Automatic

Are you looking to adapt your early Pontiac V8 to a Small Block Chevy style Transmission for overdrive or ease of finding new parts? Replacing our PO201 kit, our revamped WPO301 kit adapts your engine utilizing our WilCap styled adapter plate, crankshaft adapter and Chevy 168 tooth flexplate, and high torque mini starter. Some notes on the kit:

* This kit is made to work with 1963-1964 326/336, 389 and 421(1964)Pontiac V8 engines. These engines have a "larger" BOPC engine block pattern and will have a 2.76 inch crank register diameter. Your engine block mounting face should resemble the picture provided in the kit pictures. PLEASE measure your crankshaft register if possible before ordering! There are manufacturing differences in the earlier and later model years, and we want to make sure you get the correct kit! 1961-1962 389 and 421 (1961-1963) engines have a 2.60" crankshaft register with the same "large" BOPC block pattern. If you have a 1961-1962 engine please check out our WPO201 kit. If you have a 1965 and later Pontiac V8, please check out our BPOC101 kit.

* 326/336 engines and 421 engines have multiple variations over the short year spans, please check to insure you have the correct model year for the engine.

*The "large" BOPC pattern is the same pattern as the 1965 and later pattern however it uses a larger 7/16 bellhousing bolts, rather than the newer 3/8 inch that the BOPC and SBC engines use. The crankshaft spacing is also different.

* Any 4l60e with the one piece bellhousing will require no modification. This kit is not currently able to work with the "LS" style transmissions, it must be used with a Small block Chevy style transmission (pre 1997).

*This kit can be utilized with the BOPC transmissions as well. To use this, carefully drill out the bellhousing bolt holes on your transmission from clearance on a 3/8" bolt (roughly 0.435" on most bellhousings) to a 7/16 clearance hole (29/64 drill bit, 0.453"). For bolts that travel through the bellhousing, adapter, and into the engine, longer 7/16-14 hardware will be required and is not provided.

TRANSMISSION CONTROLLER

Are you planning on using a modern a GM 4L60E, 4L65E, and 4L70E (2008 and earlier only) or GM 4L80E and 4L85E transmission with this kit? By adding a US Shift Quick 4 stand-alone transmission controller you will save $100 dollars off of the cost of your Speed Gems adapter kit.

We have additional options from US Shift. Please give us a call if you're not seeing what you need!

*Matching our adapter kits with your engine can be tricky. If you are unsure of which kit to purchase for your engine, please call customer service at (763) 767-4480. Speed Gems is not responsible for return shipping costs of mismatched kits.