I have a np435 hooked to a 300 right now. I am getting ready to swap in a 351c in the near future. I have a 10" clutch right now but I would like to go to a 11" clutch with the bigger motor. Now the question is will my bellhousing allow the 11" clutch to fit? If not do you think the 10" clutch will handle the power of the 351c?

 

your ok with a 10"but if you want the 11, it will fit you can even go to a 12",but the smaller the less weight. less on the motor.but if your pullin weight at a low speed or big tires 11 would last longer.

 

I plan on running 38" tires when I get farther along with this. I will just go with the 11" clutch. Thanks for the info, just wanted to clear that up. I had read somewhere that the 11" clutch didn't fit in some bellhousings.

 

On the cleveland set up what headers are you running. Did one like this many yrs ago and had to heat/rosebud the header on driver side to clear driveshaft. 79 ford 4wd with np435 36" tires. Truck kicked butt in the mud and ran well. We ran a centerforce clutch and never had any problems with this setup. I don't remember if it was 11" or not. I just remember clutch wasn't a issue. Truck ran for many yrs. The harder you turn a centerforce dual friction the tighter it bites. Centrafugal force or something like that. Motor would turn 7000rpm no problem. One of the questions you need to ask is what seat pressure does your pressure plate have. One of the problems is higher the pressure of pressure plate mean't harder foot pressure. Meaning worn linkage issues and other related issues at rods and other places. Centerforce solved a lot of these issues with lighter foot pressue and once you throttle into motor the centerforce started hooking up. Their might be other new products out their but this dual friction worked well in our application. Drop me a PM if any questions. It was a fun truck to run back in the day.