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on the Internet for over 30 years! and not clogged down with Ads! Again, thanks! | | | | Joined: Nov 2005 Posts: 43 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2005 Posts: 43 | Is the Clark 5 speed the same bolt pattern as a small block or big block Chevy if my 292 doesn't fire I might yank it in favor of a v8a
Jdude
| | | | | Joined: Nov 2006 Posts: 2,544 Shop Shark | | Shop Shark Joined: Nov 2006 Posts: 2,544 | | | | | | Joined: Jun 2004 Posts: 8,597 Riding in the Passing Lane | | Riding in the Passing Lane Joined: Jun 2004 Posts: 8,597 | The bell housing that fits the 292 will fit the V-8. They say money can't buy happiness. It can buy old Chevy trucks though. Same thing. 1972 Chevy c10 Cheyenne SuperIn the Gallery Forum | | | | | Joined: Apr 2001 Posts: 268 Shop Shark | | Shop Shark Joined: Apr 2001 Posts: 268 | Which Clark 5 Speed?
Actually Chevy and GMC both used the same bolt pattern for all the manual gear boxes. Only change was the hole for the front bearing retainer.
Not sure which year the change came into play. I think it was when the 4 speed changed from the SM420 to the SM465, (just a guess) the bearing retainer hole was enlarged. But the 4 hole bolt pattern remains the same for 4 speed or 5 speed.
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1948 GMC FC101 1/2t Pickup w/270 and SM420 1948 GMC FC253 1t Factory 80"x9' Flatbed Dually 1948 Chevy COE 2 Ton 8'x15' Flatbed 1950 GMC 354-24 2 Ton 8'X12' Flatbed w/Dump Hoist 1953 GMC 454-30 3 Ton 8'x14' Flatbed w/Dump Hoist 1953 GMC 454-30 3 Ton Cab and Chassis 1942 Clarkator 6 MILL-44 Heavy Aircraft Tug 1942 Ford (9N) Moto Tug with 1/2 yard Loader 1947 Oliver OC3 HG-42 Tract-Crawler Bull Dozier w/6' Blade
| | | | | Joined: May 2005 Posts: 8,878 . | | . Joined: May 2005 Posts: 8,878 | GM transmission bolt pattern may be the same but the heavier duty setups often used larger diameter flywheels than the same engine in a small truck, bigger clutches. And where you can get into trouble trying to swap is longer (often larger too) input shafts in the transmission. You can machine a spacer or if available swap the smaller input shaft to get the transmission from a big truck to fit a small, or rather shallow, bellhousing. Other way around putting a small truck transmission with common input shaft on a big truck bellhousing can result in the input shaft being too short to reach the pilot bearing, might not be anything to do about that... swap input shafts if you can.
Advance Adapters may have the spacer and I'm sure they have the input retainer adapter... what is it, 4-11/16" to 5-1/8" ? | | | | | Joined: Nov 2005 Posts: 43 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2005 Posts: 43 | it is for my 51 gmc 450 3 ton with a 292 chevy six
Jdude
| | | | | Joined: Jan 2008 Posts: 4,961 'Bolter | | 'Bolter Joined: Jan 2008 Posts: 4,961 | A 450 series should have room for the larger clutch housing and 60 series Chev used the big clutch housing. Which clutch housing do you have? | | | | | Joined: Nov 2005 Posts: 43 Wrench Fetcher | | Wrench Fetcher Joined: Nov 2005 Posts: 43 | I don't know I could post a pic if it might help.
Jdude
| | | | | Joined: Sep 2006 Posts: 1,276 Shop Shark | | Shop Shark Joined: Sep 2006 Posts: 1,276 | I am close to you and mite be able to help. If you have a 292 someone has already done an engine swap on your truck.As wrenchbender stated above the belhousing that is bolted to your 292 will bolt to a small block, big block or 90* V6 Chevy.
Last edited by HevyHauler; 01/31/2014 2:03 AM.
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