Hi all, I have been making drawings lately while machining a custom flywheel on the side, for my diesel fj60 project. I'm kind of stuck wondering how many bolts are really needed to hold a bell onto an engine? On my old c10 there's a clutch inspection cover that goes on the bottom of the bell, and literally encompasses the profile of a good 1/3 of the clutch radius. On some vehicles though, it seems the whole diameter of the bellhousing is bolted straight to the block. While figuring out my adapter plate, I wanted to ask those of you who might be able to guide me, is it OK for me to have a sheet metal cover on the bottom 1/3 of the mating surface in lieu of a longer plate for the bell to bolt onto? Sorry for my poor explanation this is just a quick post while on my lunch break. Thanks for your guys' help! BTW it's a nv4500 to om617 swap, using an advance adapters bellhousing for a 90's LS. I tagged this with GM because it's the most applicable tag I think
GM Unusual bellhousing question (1 Viewer)
- Thread starter Foam
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It would have more to do with the design and strength of the bell housing itself than anything. The cast iron BH you are referring to have lots of strengthening ribs on the outside, it is thick and heavy.
Others are lighter weight, but are all-encompassing.
I would start first and foremost with what the back of the block requires. If it is a "full face" bolt on, then I would consider going there. However, I'll bet there are adapters already out there to do what you're looking for.
Since diesels produce lots of torque, you're probably going to want to go as much full face BH as you can muster. Usually the adaptation takes place between the BH and the transmission, rather than between the engine and the BH.
I would say at least 6 bolts. This seems to be the minimum on most cars and light trucks. A couple of locating dowels would also be ideal. GM stuff all had locating dowels in the outside edge of the block. Those hold a lot of the torque load and kept everything centered.
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Whiskerz, BILT4ME, perhaps ideal to incorporate another locating dowel, if I can't muster up enough bolt holes? There is certainly room for at least another. The drivetrain is a heavy mf'er and the back of the block is nowhere near as wide as a smallblock, so I'm mainly worried about the weight being supported and staying centeredthan torque twisting it around. Sure my little 3 liter diesel is a bit torquey, but I'm sure it's nowhere near the beef needed to overdo a 'mock' stock setup, so maybe theres room for a small compromise. I'm not sure I can include all of the bolts, mainly because the back of the block overlaps some of the bottom holes on the bh.
This has got me thinking, though. The main reason I asked this question was to know if I need to make another plate, since the one I have is a little small and doesn't cover the whole face of the bellhousing. I'm unsure if I can even incorporate all of the bolts WITH a bigger plate though, since the back of the block kinda overlaps some of the holes. I suppose that's enough bantering for now, thanks for your input guys its much appreciated!
This has got me thinking, though. The main reason I asked this question was to know if I need to make another plate, since the one I have is a little small and doesn't cover the whole face of the bellhousing. I'm unsure if I can even incorporate all of the bolts WITH a bigger plate though, since the back of the block kinda overlaps some of the holes. I suppose that's enough bantering for now, thanks for your input guys its much appreciated!