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Apr 26th, 2026 | | AD Chevy Trucks  Over 6,000 pictures Brad Allen has an awesome collection of Chevrolet factory pictures that he has set up from film strips. Check them out!
Lots of work on Brad's part ... pure enjoyment (and references) for you!
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| | | | Joined: Oct 2021 Posts: 6,902 'Bolter | | 'Bolter Joined: Oct 2021 Posts: 6,902 | What's the big hole in the bell housing for on the driver's side? Basically, it's a mirror image of the timing hole on the passenger side but slightly larger.
Last edited by Otto Skorzeny; 10/10/2026 9:43 PM.
1950 Chevrolet 3100 (Ol' Roy)
1939 Packard Standard Eight Coupe (The Phantom) | 1956 Cadillac Coupe de Ville (The Bismarck) | 1964 Ford Galaxie 500 coupe |1966 Ford Mustang (Little Red) | 1969 Pontiac GTO (The Dishpit) I 1979 Ford F-100 | 1976 Ford F-150 (Big Red) | 1995 Ford F-150 (Newt)
| | | | | Joined: May 2015 Posts: 11,113 Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums | | Housekeeping (Moderator) Making a Stovebolt Bed & Paint and Body Shop Forums Joined: May 2015 Posts: 11,113 | It's there to make Otto ask questions. 
Kevin 1951 Chevy 3100 work truckFollow this saga in Project JournalPhotos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together. | | | | | Joined: Feb 2004 Posts: 29,837 Kettle Custodian (pot stirrer) | | Kettle Custodian (pot stirrer) Joined: Feb 2004 Posts: 29,837 | Ventilation for clutch cooling, most likely- - - - -although it might be possible to add a pointer to time the engine on a cylinder different than #1.
Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!
| | | | | Joined: Jan 2022 Posts: 2,478 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,478 | It's used for the timing pointer south of the equator where the engines turn the opposite direction.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Mar 2007 Posts: 3,432 Crusty Old Sarge | | Crusty Old Sarge Joined: Mar 2007 Posts: 3,432 | Do the GMC engines use the same Bellhousing? Could it be for timing marks on one of those?
~ Craig 1958 Viking 4400"The Book of Thor"Read the story in the DITY1960 Chevrolet C10"A Family Heirloom"Follow the story in the DITY Gallery'59 Apache 31, 327 V8 (0.030 over), Muncie M20 4 Speed, GM 10 Bolt Rear... long term project (30 years and counting) If you don't like driving yourTruck, you won't drive yourTruck..| Living life in the SLOW lane | | | | | Joined: Mar 2010 Posts: 10,296 Renaissance Man | | Renaissance Man Joined: Mar 2010 Posts: 10,296 | Anyone know that there is a plug that is supposed to go in there? It is made of what appears to be rubber which would explain why they aren't found very often. Rubber does not last anywhere near 70 years.
I have one. It is black and has a crown on the exposed surface. Its density is similar to a hockey puck.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
| | | | | Joined: Jan 2022 Posts: 2,478 'Bolter | | 'Bolter Joined: Jan 2022 Posts: 2,478 | Do the GMC engines use the same Bellhousing? Could it be for timing marks on one of those? GMC timing window is on the same (starter) side of the engine that Chevies are.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12
'52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
| | | | | Joined: Feb 2016 Posts: 1,992 'Bolter | | 'Bolter Joined: Feb 2016 Posts: 1,992 | I would believe that a reverse rotation stovebolt engine would exist. Marine, industrial, military, etc. would probably be customers.
1957 Chevrolet 5700 LCF 283 SM420 2 speed rear, 1955 IH 300U T/A, 1978 Corvette 350 auto, 1978 Yamaha DT175, 1999 Harley Davidson Softail Fat Boy
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