Specifically the back of the motor? We are working on an adaptor of sorts... and need the X and Y coordinates for the dowel pins in relation to the crankshaft centerline. I thought I have seen them on line somewhere... but cannot find them. TIA! Sam
You may want to double check this - as I cannot remember the reference I used. Sorry for the "extra" holes - the CHEVY stuff is in WHITE!
the old Chevy Power book shows the rear view of the big block engine with the dowels 2.32" above the crank CL, and 7.69" to either side.. big and small blocks are the same in that regard.
See if you can get your hands on one of those Chev V8 to BOP trans adapters. That should give you the pattern for the back of the engine. I've got on out in the shed but I think it is in too bad of shape to get a good pattern off.
What I needed wer the X and Y coordinates that Hemi and Squirrel gave me so Tim and I can zero out the mill to find center on the adapter we are making for the Bonneville Banger... GM 3 speed manual trans to Model A motor... I'll share a How-To once it's done. Sam
Excellent, !!!shoulda lookat this first. I see the measurements for the dowels are centerlined as well. Thanks a bunch Ian
I am now looking for the x-y drawing for the 170 6 banger without much success......BUT I did make an accurate as possible tracing of the stude spacer plate that goes between the bellhousing and the block, this should give me a fairly accurate location of the block holes.I am hoping the large center hole of the spacer plate that slips over the crank flange is center to the rest of the block holes.I have found center for that hole and transposed the tracing to the center of your x-y chevy pattern and I should have the adapter plate. Now to match up a starter (same 10-12 tooth pitch as the chevy flexplate) and get my tooth clearances right, to bore the starter hole and mounting bolt holes in the right place in relation to the flexplate.Then I have to make a crankshaft-flexplate adapter as the stude flange bolt pattern is a tad off from the chevy flexplate (understandable). Put it all together and I should be able to do the swap.Your print is the cornerstone to my project, again I thank you so much. Also I found that the crankshaft flange and bolt spacing on the stude v8's are the same as my flat 6 and probably the 6 cyl OHV 170 version circa 59-61. The v8 adapters that are made by several people seem to use the same system to "center" the adapter plate in relation the the crank flange. They use a sleeve that fits snugly over the od of the flange,and the od of that sleeve fits into the round bore of the adapter, thus locating the plate. Snug up the adapter plate bolts, remove the sleeve. Some recommend drilling 2 holes thru the plate and into the block face and install a dowell or 1/4" roll pin, so one wouldn't have to center it all over again. Thats my story and I'm sticking with it.........update my third picture is the dummy adapter, and 4th with starter.....5th is with a 4L60E bellhousing attached and dialing in the adapter plate, got it down to .002. Now to save all my patterns and transfer to some 3/4" 6061 plate. Update: 2/11, plate is done, trans mounted, now to make TV brackets and linkage......... Ian
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