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WadmalawJoe · 03-15-2013, 05:16 PM

Well, I adjusted timing down to 8 degrees but nope.....still doing it. It is reading 47 degrees at all in at 3,000 rpm, its actually all in well before that.
Here is some more info,
I rigged up my multi-meter/tachometer to reach inside the cab.
The detonation issue happens at 2,500-2,600 rpm (50-55 mph)
I came back, reconnected timing light and noticed its all in (47 degrees) around 2,100-2,200 rpm.

Should I go with a heavier spring so it goes all in later or just back the timing down more?

03-15-2013, 05:16 PM	#51
WadmalawJoe Registered User Join Date: Oct 2012 Location: Ravenel SC Posts: 317	Re: HEI distributor tuning problem Well, I adjusted timing down to 8 degrees but nope.....still doing it. It is reading 47 degrees at all in at 3,000 rpm, its actually all in well before that. Here is some more info, I rigged up my multi-meter/tachometer to reach inside the cab. The detonation issue happens at 2,500-2,600 rpm (50-55 mph) I came back, reconnected timing light and noticed its all in (47 degrees) around 2,100-2,200 rpm. Should I go with a heavier spring so it goes all in later or just back the timing down more? __________________ Toys/projects Many toys, not enough time to play! My youngest son and I picked up a 69 Chevy C-10 on 1/7/22, this is my second 69, it was 10 years ago that I had my other one. So I’m back!!!