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#76043 04/07/2007 6:17 PM | Joined: Nov 2000 Posts: 582 Shop Shark | | Shop Shark Joined: Nov 2000 Posts: 582 | Trying to get my tuning done on the 261. Have Langdon's mini-HEI and two dual Holley Webers on the Offy intake.
1. Painted the pin and ball on the flywheel housing. Using a timing light, if I adjust the distributor to line up the ball with 0 advance on the light, I can get the idle down to a reasonable amount. If I set the advance on the light to 10 degrees and readjust the distributor to match up the ball, the idle stays at 900 rpm all the time with both idle stop screws fully out. Am I missing something or using the light wrong?
2. Do you use a dwell meter to check the mini HEI? I know dwell on GM breaker points is about 30 but my meter shows about 20 on dwell.
3. Vacuum gauge is readinging steady in the green area at about 20 to 22.
4. Gapped the plugs at .060 as Langdon suggested in his specs. Truck has a bit of misfire at idle.
I would appreciate advice and guidance from anyone who has tuned up one of these setups. | | |
#76044 04/07/2007 8:21 PM | Joined: Dec 2006 Posts: 1,464 Shop Shark | | Shop Shark Joined: Dec 2006 Posts: 1,464 | 49 - I can't comment on the Holley Webers but I am using the Langdon mini-HEI. I did think of a couple of things as I read your post:
1. Did you remove (and plug) the vacuum line from the advance mechanism on the distributor before you checked your timing?
1. No, you don't use a dwell meter on an HEI.
Good luck, hope you get it ironed out. | | |
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