defecater
Full Access Member
Recently I completed my own version of a SMF conversion after the clutch started slipping in a neawly aquired 88 F-250 that I had just installed a Banks Sidewinder turbo into. Being a cheap ***, I did not want to buy a conversion flywheel, but I definitely wanted to upgrade to a 12 inch clutch-(cant do that with a bolted/welded SMF) I have a lot of parts and parts tucks, so I thought I would see what kind of combo I could come up with to accomplish my goals.
After spending quite a few hours bolting various components together and measuring everything I thought was relevant, I came up with using a 6.9 4 speed flywheel and re-drilling it for a 12 inch clutch pattern from a 460 ZF application.
I was still coming up 1/4 inch short in my measurements for where the throwout bearing should be positioned to get the proper travel from the hydraulic master and slave cylinders. I solved that by fabbing up a 1/4 inch spacer. On my particular setup, the original thowout bearing had a snap ring on the backside that I removed and slid the spacer right onto the bearing. I hated the idea of re-using a throwout bearing when there was a brand new onr in the 460 clutch kit, but the snap ring on the old one made the job a lot easier. The old bearing seemed to be OK other than the bearing was a bit dry. I was able to work some fresh grease down into the bearing using a needle adapter on my grease gun, so I think it will be fine. I cant say what throwout bearings are in other clutch kits, but the one in mine had a sort of plastic sleeve without the snap ring that centered it over the input shaft bearing retainer. I suppose I could have made the 1/4 inch spacer and then cut it in half and welded it back together after positioning the two pieces around the throwout bearing, but using the original after getting some grease back in it seemed to be a better idea at the time.
Pulled two wheeling rigs on a 32ft gooseneck trailer last weekend with it and it does just fine with the new clutch setup. It certainly growls a lot more at idle, but I was expecting that anyway. I did put 2 gallons of synthetic 5w-20 in the transmission. I was having trouble downshifting from 5th to 4th, so I will likely drain out the motor oil and try some synthetic ATF.
Just another option if anyone is interested.
After spending quite a few hours bolting various components together and measuring everything I thought was relevant, I came up with using a 6.9 4 speed flywheel and re-drilling it for a 12 inch clutch pattern from a 460 ZF application.
I was still coming up 1/4 inch short in my measurements for where the throwout bearing should be positioned to get the proper travel from the hydraulic master and slave cylinders. I solved that by fabbing up a 1/4 inch spacer. On my particular setup, the original thowout bearing had a snap ring on the backside that I removed and slid the spacer right onto the bearing. I hated the idea of re-using a throwout bearing when there was a brand new onr in the 460 clutch kit, but the snap ring on the old one made the job a lot easier. The old bearing seemed to be OK other than the bearing was a bit dry. I was able to work some fresh grease down into the bearing using a needle adapter on my grease gun, so I think it will be fine. I cant say what throwout bearings are in other clutch kits, but the one in mine had a sort of plastic sleeve without the snap ring that centered it over the input shaft bearing retainer. I suppose I could have made the 1/4 inch spacer and then cut it in half and welded it back together after positioning the two pieces around the throwout bearing, but using the original after getting some grease back in it seemed to be a better idea at the time.
Pulled two wheeling rigs on a 32ft gooseneck trailer last weekend with it and it does just fine with the new clutch setup. It certainly growls a lot more at idle, but I was expecting that anyway. I did put 2 gallons of synthetic 5w-20 in the transmission. I was having trouble downshifting from 5th to 4th, so I will likely drain out the motor oil and try some synthetic ATF.
Just another option if anyone is interested.
Otherwise, anybody else who gets it is going to be pulling their hair out trying to do a clutch job on it.
