68 L78 Holley vacuum advance question

alben · #1 03-26-2006, 09:35 PM

My assembly manual for 68 Camaro shows vacuum port just rear of the passenger side carb base bolt on the DZ Holley. There is no vacuum at this port at idle, it opens to a hole above the throttle plates, which are closed at idle. Is this correct, no vacuum is reqd at idle/ Also, my only book showning initial timing advance(68 Chevrolet chassis service manual) shows 4 degrees before TDC is this enough advance? Help will be appreciated. Thanks

Keith Tedford · #2 03-27-2006, 12:55 AM

The distributor was set up with emissions in mind. Take it to a shop with a distributor maching and have it set up with a performance curve. Lots of easy hidden horsepower to be had.

alben · #3 03-27-2006, 01:05 AM

Thanks much, I couldn't understand why so little advance, any distributor shop you can reccomend, also to redetail distributor at the same time?

**TDW** · #4 03-27-2006, 02:56 AM

I had a distributor done by MacNeish. Very nice work. www.z28camaro.com

alben · #5 03-27-2006, 03:03 AM

Thanks, can you give me MacNeish contact info?

**TDW** · #6 03-27-2006, 03:27 AM

If you click on the link I posted, it takes you to his web site. Tell him Tony in Michigan said hello.