Can timing gears be this for off? [Archive] - Chevelle Tech

: Can timing gears be this for off?


bob_adamsky
Jul 13th, 04, 10:08 PM
Just came in from my garage trying to degree my UD 288/296F7.After reading numerous post on degreeing I installed the crank gear on +4 mark and came in at 97 ICL (should be 101 ICL) as marked on the card. I did try 3 more times and even rechecked TDC and got the same.I moved the crank gear to 0, thinking I would get my 4 degrees and be good. Now after many tries I get 105-105 1/2 every time. Did I miss something or is this timing set this far off? Open to any suggestions. Thanks

Tom Mobley
Jul 13th, 04, 11:56 PM
What timing set are you using? Some of them move the cam 4 **camshaft** degrees (eight crankshaft degrees) I thought most modern manufacturers had dumped this idiot deal but possibly you've got one. 105 - 97 = 8. Easiest way around it is to buy a different timing set. Old Cloyes TRue-Rollers were like this. I think recently manufactured CLoyes are OK. Edlebrock makes some decent sets, work right.

You can drill out the dowel pin hole in the upper gear and install offset bushings, but it's a PITA, the gears are hard and don't drill well. To go that route I'd plan on taking the gear to a machine shop and have it done on the mill. You don't want to drill it off center or have the hole with hourglass shaped sides and whatnot like that. Also, if you go that route be prepared to degree it in several times, changing the bushing to get the right numbers. Run one of the little cam bolt lock plates to keep the bushing from working out the front. Some guys would re-drill the hole from the back, not going all the way though. The lip would keep the bushing from ever walking out.

My advice? Get a different timing set. Make it easy on yourself. Your time is worth something, right?

Tom

bob_adamsky
Jul 14th, 04, 6:53 AM
Thanks Tom, the set is new true roller from Summitt.I thought moving the from 0* to +4 mark should have moved the cam 4*, not 8 like I am getting.

Mz28att
Jul 14th, 04, 8:41 AM
Arnt Harolds cores 4 degrees advanced already?

MaTt

Pat Kelley
Jul 14th, 04, 10:20 AM
I think Tom is probably right. You could call Summit and see what they say.

bob_adamsky
Jul 16th, 04, 12:09 PM
UPDATE: Called Summit, they told me it sounds as the set is marked wrong, and the would replace it. Also asked if I would try -4 mark and see what I came up with.

Guess this would be a good reason to degree and recheck even parts that are new and of decent quality