I have been a member for some time, but usually got all my questions answered by Duke Williams, or Scott Marzahl away from the forum. I have suddenly run into a real road block.
I have a 327/375 Corvette engine with stock 1963 Rochester fuel injection in a 56 Arnolt Bristol. I just re-built the engine and added a set of after market aluminum heads. After nearing completion of the build up, I discovered that the heads are thicker than stock, and there is no way the air meter from the F.I will clear the stock valve covers.
I have thought up four ways to circumvent the problem. None are both easy and acceptable.
(1) Replace the aluminum heads with the original cast iron 461X heads. (This would negate the front end weight loss I was trying for.)
(2) Buy some cheap stamped valve covers and "beat them into submission." (not exactly cool)
(3) Have spacers made, 1/4 to 3/8 inch thick to match the plenum to base manifold gasket, raising the plenum. (Probably not cheap)
(4) Go back to the 1969 Z28 manifold and 780 Holley I had on it while the Rochester unit was t/u. (I just had the F.I. re-built by Jack Podell).
Have you thought about C4 aluminum heads ('89 or later)? They're very light and (I believe) are the same height as stock heads. Look in Dave Vizard's book "How to Build and Modify Chevrolet Small Block V-8 Cylinder Heads", Chapter 13. If you compare the flow numbers Dave obtained with those obtained from ported 461-X heads in Super Chevy, Dec. '07 (p.88), the you'll see that they're just as good on the intake ports and better on the exhaust ports.
I have a pair in my garage and I'll try to measure them for you.
Thanks for posting this. I have a '64 L76 with A/C and always thought it would be so cool to have F.I. in there with some aftermarket heads, hydraulic roller cam, etc. Now I know to save my money...on the heads anyway!!
Buy sheet aluminum valve covers and have them cut and rewelded at the interference points.
Plan B. machine the heads raised valve cover lip. Heads like AFR have next to no lip. But they have the problem of oil flowing above the valve cover gasket. So you have to run the best gaskets tight.
Thanks for the help. I have sent individual E mails to the two replies. I solved the problem with 3/8 inch aluminum spacers. It will be quite a while until the car is on the road, so how it all works out is a guess.
Arnolt 57
I suspect you will find that the old Rochester FI unit doesn't make the power you might suspect it would. A good intake and carb setup will out perform it hands down.
I suspect you will find that the old Rochester FI unit doesn't make the power you might suspect it would. A good intake and carb setup will out perform it hands down.
Maybe, if you're talking about an Edelbrock Performer RPM and one of their 750 cfm carbs. But in comparison to the original 365HP intake and one of those POS Holley 600's, then it will outperform that setup while running smoother and getting better gas mileage.
Corvette Store
After market heads and Rochester F.I.
