Daniel,
Ditto what John said - might be that the builder used the wrong tab. First
step is to confirm if the 0 mark is inded TDC. Take an old spark plug,
hammer out the electrode and ceramic. Then find a bolt that fits the hole,
grind the head off it to a full round and epoxy (or braze) it into the old
plug to make a piston stop. You want the bolt to stick out about an inch on
the electrode side.
Pull off the driver's side valve cover and pull the #1 plug. Disconnect the
power wire from the distributor and remove the cap. Bump the engine around
around til the rotor is pointing to the position of the #1 terminal on the
cap and then check the rockers on #1 to be sure your on the compression
stroke - both valves should be closed. If not, bump it around again to the
#1 position. Screw in the piston stop you made, and manually turn the
engine forward til you feel it stop. Make a mark on the balancer that
corresponds to zero on your timing tab. Rotate the engine in the opposite
direction and make another mark. The two marks should be approx. equal
distances away from the single mark on the balancer. If they're not even
close, then you've got the wrong timing tab. If its right, then suspect the
distributor.
I would guess that the Jag's 350SBC has an HEI distributor ( most
conversions use it)? If so, and it was that advanced, it very possible that
the weights for the mechanical advance have worn into elongated holes. The
older generation of HEI were notorious for this. Crane has a kit with new
advance plates, weights, bushings, and an assortment of springs for a
reasonable price. I know Advance Auto carries it, and I think Autozone does
as well.
If you're looking for performance, here's a timing/tuning link
http://www.73-87.com/garage/hei.htm
I've got the Crane adjustable vac. adv. unit he talks about on both my Chevy
motors.
A good place for HEI pieces parts http://www.kendrick-auto.com/ignition.htm
A good book which has a section on rebuilding an HEI is "How to rebuild your
small block chevy" by David Vizard - amazon has it for $14, or you could
probably find it at a larger library. Has complete chapter with lots of
step-by-step photos for r&r' ing an HEI. If you have a hard time finding
it, I could scan the pages for you, but you'd get some greasy fingerprints
along with the text.....
Mark Sedlack
ZROC
Cuyahoga Falls OH
66 1600 http://www.mildevco.net/chevypowereddatsuns/
77 280Z http://www.mildevco.net/chevypowereddatsuns/
----- Original Message -----
From: <JOver4X4@aol.com>
To: <neuman@RadOnc17.UCSF.Edu>; <datsun-roadsters@autox.team.net>
Sent: Thursday, December 11, 2003 11:01 PM
Subject: Re: Super advanced timing?
> Daniel,
>
> Chevy used several different harmonic balancers. Different diameters too!
> You need to find the correct timing tab for your balancer. They make an
> aftermarket universal scale where you zero it out at TDC. You will have
to find top
> dead center, mark your harmonic balancer and then align the "0" to your
new
> TDC mark and go from there.
>
> If you need info on finding TDC just holler. I'd be glad to guide you
> through it.
>
> Good luck.
>
> John Over
> 68 2000
> 67 1600
> 46 Willys Jeep (small block Chevy)
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