Author Topic: Shag has gone Cleveland (Read 1250 times)

cmayna · « **Reply #25 on:** August, 17, 2009, 08:13:03 AM »

Dave the machine shop had written on the valves numbers from 60, 60.5 & 61cc. This was on the larger valve which I assume is exhaust. The average is 60.62cc.

daveSanborn · « **Reply #26 on:** August, 17, 2009, 09:17:18 AM »

Well, you had a 50/50 shot.... the larger valve is the intake valve.

If possible, compare the exhaust ports (where the exhaust manifold/header bolts on) on the 4V heads with those of any aftermarket small block cylinder heads.

Notice that the exhaust ports are likely 50% larger than any other head.

monkeystash · « **Reply #27 on:** August, 17, 2009, 09:41:27 AM »

Craig,
Here is a good article on Cleveland heads from Ford Muscle. You need to be a subscriber to view past page 1. If you aren't, let me know and maybe I can PT you the text from the other pages.

http://www.fordmuscle.com/archives/2007/10/351CHeads/

cmayna · « **Reply #28 on:** August, 17, 2009, 09:48:16 AM »

Dave,
Just measured the width and height of the exhaust port openings on both Shag's 302 heads and the cleveland heads. These are approximate only.

Width Height
302 7/8" 1-1/4"
351 1-3/4" 2-1/8"

Diammm, Almost twice the size.

daveSanborn · « **Reply #29 on:** August, 17, 2009, 10:15:52 AM »

Width X Height = Square Inches of port area (approximate)
302 7/8" 1-1/4" = 1.09375
351 1-3/4" 2-1/8" = 3.71875

From just over 1 sq.in. with the 302.... to just under 4 sq.in with the 4V Cleveland. Do you now understand the term "the 4V likes to breathe"?