1974 Nova Backfire HELP!!

MAURICE BLENDHEIM · 06-22-2012, 08:21 PM

I would check the valve springs and installed height. They should be at least 135@1.75 on the seat and 295@ 1.25 open. Do you have a single spring with damper? This cam requires a double spring and a 1.44 seat diameter. What rockers do you have? If they are stock, you will not have the required slot length to accept the lift. This cam has characteristics of creating all sorts of issues and won't co-operate with low static compression. 12 years of backfiring...hope we can help.

06-22-2012, 08:21 PM	#9
MAURICE BLENDHEIM Senior Member Join Date: Jun 2011 Location: Langley (no igloos), British Columbia, Canada Posts: 569 Likes: 310 Liked 284 Times in 87 Posts	Re: 1974 Nova Backfire HELP!! I would check the valve springs and installed height. They should be at least 135@1.75 on the seat and 295@ 1.25 open. Do you have a single spring with damper? This cam requires a double spring and a 1.44 seat diameter. What rockers do you have? If they are stock, you will not have the required slot length to accept the lift. This cam has characteristics of creating all sorts of issues and won't co-operate with low static compression. 12 years of backfiring...hope we can help.