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**Boog** · 07-12-2018, 10:50 PM

I think he said it only has 6" of vacuum. That's not enough for power brakes. Either that is a real radical cam or there is a leak. It could even be the power brake booster leaking. I once had a spring in a booster break and the broken end of the spring wore a hole in the diaphragm which began to leak. It finally got bad enough I could hear the leak when I leaned up near the booster. The truck also idled like it had a large cam in it too but it was bone stock.

07-12-2018, 10:50 PM	#104
Boog laying low Join Date: Mar 2001 Location: Searcy, Ark. USA Posts: 12,959	Re: Install thread- Holley EFI Sniper on '72 402 big block I think he said it only has 6" of vacuum. That's not enough for power brakes. Either that is a real radical cam or there is a leak. It could even be the power brake booster leaking. I once had a spring in a booster break and the broken end of the spring wore a hole in the diaphragm which began to leak. It finally got bad enough I could hear the leak when I leaned up near the booster. The truck also idled like it had a large cam in it too but it was bone stock. __________________ Boog 69 Chevy stepside, 358/T350, 4.11 posi, 4.5/4 drop, rallys, poboy driver primer is finer 91 Chevy sportside, Tahoe, Yukon & GMC Crewcab All GM..'nuff said. I stand for the flag and kneel at the cross