#5 heads in 68

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June 18th, 2012, 05:17 AM

72 Supreme

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Join Date: Apr 2007

Location: Millville,N.J.08332

Posts: 97

#5 heads in 68

Are these the correct heads for my 68 350, what are the valve sizes and compression ratio for the stock engine?
Thanks,
Doug

June 18th, 2012, 07:22 AM

joe_padavano

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Join Date: Mar 2007

Location: Northern VA

Posts: 47,300

Quote:

Originally Posted by 72 Supreme

Are these the correct heads for my 68 350, what are the valve sizes and compression ratio for the stock engine?
Thanks,
Doug

#5 heads were factory installed on ALL 1968-69 350s, including W-31s. All had the same 64-ish cc chambers (actual chamber volume varies with manufacturing tolerances). CR was changed with piston dish size - large dish pistons provided 9:1 CR, small dish 10.25:1, flattops (on W-31s only) were 10.5:1. Valves were 1.875/1.562 on all except W-31s, which got 2.000/1.625 valves.