Anything to gain by porting Edelbrock RPM heads?

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Can someone elaborate a little about CNC porting? I seem to bypass most magazine articles on porting, but I seem to recall that it involves a computer programmed machine instead of porting by hand?
If so, I suppose the advantage is a more consistant port size from cylinder to cylinder?

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I think that all of the CNC programs are based on hand porting two cylinder ports, a left and right hand port(I hope that makes sense ) to get the optimum flow and then have the CNC probe measure and store all the numbers in its memory and make all the other ports match those two, one left hand and one right hand If I'm wrong I hope someone will correct me Jeff, Dan, Todd?

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Can someone elaborate a little about CNC porting? I seem to bypass most magazine articles on porting, but I seem to recall that it involves a computer programmed machine instead of porting by hand?
If so, I suppose the advantage is a more consistant port size from cylinder to cylinder?

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whats the next head up from the edelbrock. is it worth upgrading the heads instead of cnc porting?

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With the right cam and heads your 493 will make 600 hp, actually it shouldn't be hard. To get there you need around 300 cfm at 28" depression, the standard. You are at 260-270 now. an extra 30 cfm can mean more than 60 hp.

Think about it...if you built a stroker you must have wanted more power. Porting the heads is a proven way to get there, you would notice the difference with the cam you have now.

Going "the next step up" in an Edelbrock head puts you into the realm of offset rockers, more on the race side. I'd say don't do it unless you are a strictly quarter mile guy.

Jeff at Modern Cylinder heads seems to have the program for CNC porting these heads. As said above, a CNC program starts with an optimized port. It is then measured and the dimensions changed into directions for a computer numeric controlled milling machine. The machine does every port the same and it doesn't require a skilled individual to do it by hand. The net result is the best port for every cylinder. The hard part is getting the right port and making a program.

R. [/quoI agree 100% with Dog. Why bother stroking it then? Its a 493, let it breath.

Another example, such as Johns above, but totally different car, 3600# leaf spring foot brake bracket car, has gone 10.06 @132+, and goes and goes and goes. Not even really optimized, because its in bracket mode. Uses a shelf .650 Comp cam. Heads were 296@.550, 304 @ .600

The Eddy heads work very well. These heads were hand ported.Stuff it in the 2500# Duster below, and probably similar results, although I'd think the Duster has more lobe seperation and more lift, just guessing.

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whats the next head up from the edelbrock. is it worth upgrading the heads instead of cnc porting?

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Thats awesome John...did you do those heads? .700 ish lift? Electronics or Non Electronics car? How many CI" ?

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Tom Hemphill from Clarksburg, Pa. either did the heads for him or guided him through the process. He runs in the Top Class (electronics) and Todd I am not really sure about engine specs but I know its a stock block. His Dad runs the "Tim's Toy" 68 Charger. I know Tim has clicked off some 8.60's with an Indy block and a set of B1BS heads that Tom did for him.

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That Charger looks just like a car that used to be pink, that ran out East, usually Lebanon Valley. Same car by any chance?

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No... This car had the original 318 in it when I got it in March 2000.

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That Charger looks just like a car that used to be pink, that ran out East, usually Lebanon Valley. A kid from CT or MA. owned it, and at that time ( 7-10 years ago) his buddy was running B1/BS heads on a Duster, both cars were running in the 8's, with the Charger usually right in the 8.70-8.90 range. Same car by any chance?

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Tim has owned and raced that car for probably 30+ years. I never remember him in any other car except it. If I still had a scanner hooked up I would scan some pictures of it from the 70's when it was blue. For years it was the craziest leaving car you ever saw with the front left tire about 18" higher than the right. He had a terrible tranny explosion at Norwalk years ago and switched it over to a powerglide. He touched the wall at Quaker about 5-7 years ago and had it repainted. Its been running 8's for years and would crack a 400 block almost every year so he finally upgraded to an Indy block. Everyone always says you lose ET going to aluminum but when Tom H. dynoed it with the same combo it was only down 6hp and ran exactly the same and never used a vacuum pump on either engine. Sometimes we try to outsmart our self's.