im looking for advice on which bell housing/ clutch fork from a chevy to use behind a 270 GMC with a T5. can i use the GMC flywheel with the chevy bell housing or does that need changed out also? would like a bell with motor mounts unless all of them had the bell mount. not too familiar with what i need and the search function didnt turn up the answers im looking for
To put a T10 behind my 270 I used a 55 Chevy 6 bellhousing. Lots of chevy six bellhousings would have worked. Some have the bellhousing mounts vertical and some are on a slant. Take your pick. Assuming you have a six bolt crankshaft/flywheel flange you can use the GMC 12 volt flywheel. If you have the 4 bolt crank I am not sure what you do. I redrilled my crank
The bellhousing that came on the GMC works fine with a T5 also - standard mods are needed (i.e. shorten the input shaft) . . . vertical side bellhousing mounts from '39 - 55 first series . . . slanted mounts from 55 first series to 59
It might depend on what you are putting the 270 GMC in. For example, if it is going in a 55 -57 Chevy car, use a bellhousing for that car with a 235.
Use a flywheel from a 1938-39 Chevrolet. There is one that is drilled for the 9 bolt heavy duty clutch (taxi cabs and police cars and 1 1/2 ton trucks.) Has 139 teeth so use a 6 volt starter. The bell housing from a 1960-62 Chevrolet pick up has a hydraulic slave cylinder for the clutch. Avoid the big clutches from the big trucks and you will be allright
my 38 chevy flywheel has 6 bolt pressure plate, but it looks like its a 10" clutch. is this the same one you are talking about?
If it is out of a road tractor you have the BIG truck bell and flywheel - it is huge and fitting a T5 to that will be a mess. Switch to a small GMC pickup bell or your choice of Chevy bells and you will need a different flywheel. Of course you need to know if you have a 4 bolt crank or a 6 bolt crank . . . flywheels are not super common, but not that difficult to find if you keep your eyes open.
Don't use a big truck flywheel if you plan on running any more RPM than the truck engine originally ran. They WILL EXPLODE! Even at lower rpm, not a good idea.
No. The heavy duty clutch had 9 bolts holding it to the flywheel. It is in the old Chevrolet parts books, like 1929 to 1950.
The GMC starter will work with the 6 volt 139 tooth Chevrolet flywheel if the GMC was 6 volt and had 139 flywheel teeth. If the starter is off the engine you can find out if it is 6 volt by pulling the starter drive to the rear of the starter. If 6 volt it will come straight back. If 12 volt it will spin. The 12 volt has helical splines, the 6 volt has straight splines. The pulley on your water pump is pressed on to the shaft. It is not threaded. It can be replaced with a water pump with an 8 hole flange for modern pulleys. There are many types of flywheels for GMC and as somebody above says the big ones should not be run at excessive RPM. If the clutch has "valve springs" in it, it is too big for what you want.
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