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| | | | Joined: Apr 2008 Posts: 127 'Bolter | | 'Bolter Joined: Apr 2008 Posts: 127 | Can an SM420 be adapted to work on a 1946 with the 216 engine? | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | The bottom, right mounting bolt will have to be relocated; can drill a new hole in bellhousing or drill and tap matching hole in front of trans. Check retainer diameter, input shaft stick out, clutch spline, etc.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Aug 2005 Posts: 277 'Bolter | | 'Bolter Joined: Aug 2005 Posts: 277 | Bearing retainer diameter will be larger for SM420. You will need to either machine larger hole in 46 housing or use a 48 plus (through 52?) bell housing. If you use a 48 plus housing with a 1/2 ton 46, you will be faced with the issue of how to mount your clutch pedal. | | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | '46 bellhousing might also not allow 11" clutch, so if 10" clutch will work OK fine, otherwise use late bellhousing.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
| | | | | Joined: Jun 2011 Posts: 5,096 Crusing in the Passing Lane | | Crusing in the Passing Lane Joined: Jun 2011 Posts: 5,096 | I welded original clutch mounting ears off an early bellhousing on my late bellhousing. Others have used bolts to mount clutch arm.
Ed
'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.
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