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Timming mark question

Old Oct 23, 2002 | 05:04 PM
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Default Timming mark question

Since my engine rebuild I don't have any off the line power, the tires wont even squeek! But about 20 mph you nail the gas and it puts you back in the seat. I also noticed the car runs real rich and the timming mark is about an inch off the scale before TDC but doesn't ping. It runs smooth but Iam wondering if the cam timming is off by one tooth? :confused: This is a 350 030", 9.0-1 C.R.,Comp. Cam XE256 camshaft, ballanced crank assembly,performer int w/egr and Q-jet.,stock #...882 heads, all ports gasket matched and flaws removed, new 400THM w/shift kit ,stock converter ,True dual exh. w/crossover


[Modified by stingraynick75, 1:05 PM 10/23/2002]
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Old Oct 23, 2002 | 05:19 PM
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Default Re: Timming mark question (stingraynick75)

Did you put a new balancer on or find tdc using the #1 piston? Sometimes the balancer can slip so your reading will be off.
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Old Oct 23, 2002 | 09:30 PM
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Default Re: Timming mark question (stingraynick75)

Which way is it off the mark? If the mark on the balancer is off towards the driver's side your timing is retarded. If it's off towards the passenger side, it's advanced. Are you checking it with the vacuum advance disconnected? Was the balancer, timing tab, or timing chain cover changed during the rebuild?
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Old Oct 24, 2002 | 04:17 AM
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Default Re: Timming mark question (stingraynick75)

Harmonic Dampner was replaced. maybe thats why the mark is almost straight up w/advance disconnected.But why do I lack low end power? I should have put in a L-88 converter
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Old Oct 24, 2002 | 05:26 AM
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Default Re: Timming mark question (stingraynick75)

Iam wondering if the cam timming is off by one tooth? [Modified by stingraynick75, 1:05 PM 10/23/2002]
I think your hunch is correct. No bottom but kicks at 20 mph sounds as though cam is installed too retarded. One tooth off = about 5º @ crank ... maybe assembler got it one tooth retarded ... or (if using 3-keyway timing set) used the 4º RETARD position. Break out the degree wheel.
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Old Oct 24, 2002 | 06:53 AM
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Default Re: Timming mark question (jackson)

Thats what Iam thinking, one tooth off, the intellectual assembler probably got in a hurry :crazy: oh wait that was me :smash:
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Old Oct 24, 2002 | 12:36 PM
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Default Re: Timming mark question (stingraynick75)

oh wait that was me
:lol: be assured ... many went before & even more will follow
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Old Oct 24, 2002 | 04:21 PM
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Default Re: Timming mark question (jackson)

Iam embarrassed to say this is the first time I didn't use a degree wheel and index my cam because my 14th wedding anniv. was the following weekend and I wanted to have the vette running, well it was running!
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Old Oct 24, 2002 | 04:30 PM
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Default Re: Timming mark question (stingraynick75)

Couple thing to check: 1) I once had the vac adv hooked to an unported source and set the timing by ear. Had no low end. Switched it to a ported source and reset timing using a light and got low end power back. 2) Maybe your carb is out of whack.

Keep checking the obvious before tearing into it.
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