Did GM make 2 different timing tabs?
Thread Starter
Racer
Joined: Jun 2007
Posts: 291
Likes: 6
From: Delray Beach FL
Did GM make 2 different timing tabs?
I have a 67 impala impala built as a restmod. They used original block and I believe original timing cover but the balance it an aftermarket Summit. When I found tdc I was off about 12-14 degrees to the mark on the timing tab. When I compare the location of the tab to one on my 70 Vet is much higher uo. I went out and bought a Mr. Gasket tab and over lay on the vet and matchs perfectly in the impala its about 12 degrees off. The Impala has the tab spot welded to the timing cover.
Race Director
Joined: Jan 2000
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From: Corsicana, Tx
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There were several versions of timing tabs/balancers. Also different sized balancers.
Easy way is to find true TDC and remark the balancer unless it's a degreed piece.
JIM
Easy way is to find true TDC and remark the balancer unless it's a degreed piece.
JIM
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
Different diameter balancers require different tabs......ALSO very important change form 1968 to the 1969 Model year in position of TDC mark on harmonic balancer to allow better view of timing tab with new longer water pumps getting installed on passenger car motors....the tab was also relocated on the timing cover if you mix the wrong balancer with the wrong timing cover without checking for true TDC....big problems!
Melting Slicks
Joined: Feb 2006
Posts: 3,105
Likes: 96
From: Sunrise FL
Spend the time, remove #1 plug and make sure its at TDC!!!Then you can play with the pointers or balancer and never wonder again!!
