The Stovebolt Site Forums The Shop Area Engine Shop GMC 302 bellhousing woes. Wont fit SM420

I got a good deal on a 1953 GMC 302 hoping to replace the stock 228 in my 51 GMC 1-ton. The 302 came with a bellhousing, 6 bolt flywheel, clutch, and pressure plate. The problem is that the bellhousing wont bolt up to the SM420. The top holes on the bellhousing are ~7.75" apart, bottom are ~ 7.25 apart. On the SM420 the top holes are 8.25 apart, bottom 9" apart. I cant use the 228 bellhousing because it isnt as deep as the bellhousing that came with the 302, so that there isnt room for the 302 pressure plate. I also cant just use the 228 flywheel and thinner pressure plate with the 228 BH (having the correct bolt pattern) because the 228 FW is 4 bolt and the 302 FW and crank are 6 bolt.

Any Suggestions

Izzenhood

You probably have the bellhousing to fit the clark transmission. Here is an old trick to use the stock 302 pressure plate with the 228 bellhousing: Put the pressure plate on a drill press and use the chuck and a spare throwout bearing to press the diaphragm down as if you were disengaging the clutch. Put washers between the diaphragm and the pressure plate housing to keep it compressed. Install clutch and tranny, remove washers. It worked when installing my 302. You also should be able to do a minimal amount of grinding to make the pressure plate fit without doing the washer trick.

Jason

Sounds like a good plan. We'll try the washer trick and let you know how it went.

Thanks for the help

Izzenhood

I have a Clarke trans from a COE, free, you pick-up. It has forward facing shift lever and taller tower, so it won't work either, darn!!!! :p