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I am rebuilding my L88 '69 427. It didn't have a timing pointer on it when I bought the engine. I bought a Summit Racing gear driven timing set which doesn't appear to have a spot to mount the timing pointer (tab). I am thinking the pointer would mount on the block, which is why I'm asking this to see if anyone can help me figure this out. I am running a 7" damper. I have already bought a timing tab which is supposedly for my generation block but it doesn't match up. Any help would be greatly appreciated. I'll attach a picture of the front.
From: At my Bar drinking and wrenching in Lafayette Colorado
The stock timing tab attaches to the timing chain cover. Since you have installed a custom cover, you now need to procure or fabricate a custom pointer and set it up by doing an accurate TDC verification and adjustment of the custom pointer. That would have been best to do prior to installation of the heads, but can still be done with a TDC check tool.
I hope you know what you're in for with that gear drive system....
I would like to hear what problems I may run into with the gear drive system. I ran it on this setup for a while and didn't have any issues. I just figured it was time to get more accurate timing since I have never had it timed. It's only been adjusted by ear, so to speak.
Would you have any advice on procuring a tab or how to fabricate one? I appreciate the reply.
Replacement tabs are readily available. Just google BBC timing tab. As Lars points out, the trick will be to figure out how best to attach in the proper position.
It just bolts right to the timing cover where the two bolts are....just get a Moroso billet pointer and bolt it on.
Gear drives are old tech that only Sprint car guys....or Blown Alcohol use as the cam runs the pump drive. They are noisey and really no more accurate than a fresh chain....or belt.
High end racers use belts because it squelches harmonics.....chains do too to a lesser extent....
Cam timing and engine timing affect each other but are two completely different things. Nobody runs a gear drive to get more "accurate" ignition timing.
A galley plug at the end of the lifter oil passage in the front HAS to be tapped and a plug with a .020" hole drilled in it to oil the gear....
If it were mine, I would Not run anyone's gear drive.
That $180 tossed away will More than pay for top quality solid, seamless roller chain timing set from likes of Cloyes, Melling or Rollmaster.
Totally agree, back in the late 70's I tried a gear drive and went back to a chain. Contrary to public folklore it wasn't Bill jenkins who was the first to use the Chevy nylon gear in pro stock which was found to help with harmonics. It was "General" Lee Edwards. But who can argue with folklore.
Why did you go back to the chain drive? The only issue I have is finding a suitable timing pointer to potentially mount to this housing.
speaking per separate experiences:
Gear drives make a noticeable whine that most folk find (at least eventually) too annoying. So much so, that whine may elicit unwelcome responses from others ('specially motorheads).
Gear drives' Whine can emulate noise of a failing alternator or failing PS pump.
Although Not Pro Stock, I've read how late, great Smokey Yunick raced endurance motors & preferred to run the GM Nylon-clad sprocket; to dampen potentially-destructive valvetrain harmonics
so sorry 'bout its optics; but many a timing pointer's been made by looping a piece of welding wire under a bolt-head.
Timing Pointer Question
