Click here to see a chart showing the corrected flow for the heads "as cast".
Click here to see the flow chart for the finished head.
The exhaust gain was less than the intake but I think that just testifies to the nice factory machined valve seat angles and the full radius bottom cut on the exhaust seat. And the best part of all of this is that I never touched the seats in the heads. The flow charts will tell the story better than I can put into words but I am pretty satisfied with my results. No, I didn’t get 300 cfm peak, but I came damn close and I did it with very minimal effort all things considered. I will probably not use the factory RHS valves only because I am going to be using a big solid roller cam and I will need a longer valve stem to get the installed height I need for the big springs. I will cover the proper setup of installed height’s and such in another article. All in all I would say the RHS “Pro Comp” heads are a really good “bang for the buck” and should be just the ticket for a 302 to 400 cubic inch engine without breaking the bank.
 Here is a graph of the Intake flow comparison before and after the work. |
 And a graph of the exhaust before and after. |
Unfortunately, I have not had enough time to get much done on the short block so that will be covered next issue. I have gotten most of the parts however and a brief summary of them would be the following. For a block I am going to use a normal old junk yard jewel. It is a 1971 vintage 302 block that will be bored to 4.040”, decked to give a “0” deck height, water jackets filled with Hard Blok, a 4340 steel crank from Ohio Crankshaft (3.400” stroke), Ohio 5.400” long “H” beam rods with ARP 2000 bolts, off the shelf domed forged Keith Black pistons, a Moroso main cap girdle, TCI Rattler harmonic absorber, Comp Cams solid roller cam and lifters, and a roller timing chain.
The entire process will be shown from degreasing the old block to final assembly. I am really excited to get this project done and on the track so I will be a busy guy from here on. My wife Amy and I are expecting our first child sometime in April too so things will definitely not be boring for me this year! Until next time.
Remember, there is always hope. And, when in doubt… DO A WHEELIE !!!
SOURCE:
Racing Head Service
3416 Democrat Rd.
Memphis, TN 38118
877-776-4323
www.racingheadservice.com
