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Old 07-20-2008, 09:52 AM
ssmonty ssmonty is offline
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What RPM is the engine running rough at? The specs for that cam are for 2200-5800rpm. If you don't like the way it runs below 2200rpm then you have a cam with too much duration. Have you tried to recurve the distributor. That cams gonna need alot more initial timing than 10*. Buy a kit that will limit the distributor's mechanical advance to say 12*-14* max. Thats just the distributor's mechanical adv. range.(no vac. adv connected) Needs bushings to limit the mech. range.(not sure if there is a kit for stock HEI to limit amount of mech. adv.. I know there are spring kits to change the rate of adv.) Verify with a timing tape. Say you have 10* initial at idle with a timing light, rev it up to 3000rpm and the timing light should indicate 22*-24* if you have it limited correctly. Then adjust your initial timing to say 18* at idle by turning the distributor. Then verify with a timing light that the total timing(18* initial plus 14* dist. mech adv.) is no more than 32*@3000rpm.(no vac. adv. connected). Leave the vac. adv. disconnected temporarily, then see if it runs better on the road with out detonating.(listen for ping and check plugs for small black specs, if you have ether, you need to back off the initial or mech, or both, or slow down the mech. with heavier springs ) You will have to fine tune both initial adv. and mech adv. to get best tune, takes some time to get it just right, but these settings should get you running better without getting into detonation at WOT just to see if its your timing causing rough running. Try it! Then you will have to hook up the vac. adv. and play with it. You will probably have to get a different vac. can for the dist. that limits its adv. and when it comes in. Thats a whole other issue. You may have to get an MSD dist. for its tuning versatility?(mech. adv.)
Then you have to dial in the carb, but get the timing done 1st. You may have to get a higher stall converter/lower rear gears if you can't get it to run at low rpms to your satisfaction after getting the timing right.
Just my 2cents.
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