Power gains from port matching intake to heads?

[dragondan64]

Hey guys/girls, I am building my 69 340 and have the heads rebuilt with 2.02 1/60 valves and not polished or ported just cleaned up inside, and I am going to run an edlebrock performer rpm air gap intake and a 600 cfm holly vac street performer carb. My question is....Will I get enough power gains in the 1500 to 6000 rpm range to justify the cost of port matching the intake to the heads? My cam is a mild purple shaft cam with about .500 in lift with 1.6 roller rockers. I am not going to race it except maybe on weekends so I would like to hear opinions from you guys/girls on the benefits of this work being done or not. Thanks for your input....Danny

 

[EL5DEMON340]

It won't be a big power gain maybe a couple hp if they are not to far off. It's one of those things you do when your wanting every last HP. My issue with your engine is the 600 cfm carb I think you would be better with a 650 to 750 carb more to the 750 would be my pick.

 

[JGC403]

If you are in the process of building an engine it wouldn't hurt to do. But if the engine is complete, I don't think it would worth the cost of new gaskets to crack into it just to port match. Won't cost anything if you do it yourself, its not hard to do.

 

[Inertia]

It won't be a big power gain maybe a couple hp if they are not to far off. It's one of those things you do when your wanting every last HP. My issue with your engine is the 600 cfm carb I think you would be better with a 650 to 750 carb more to the 750 would be my pick.

xxs2

 

[moper]

IMO, it's not much $$ to have the intake and head ports gasket matched. If there is some core shift in either that will remove it. I'm sure it's worth something, more if they are really off. The question is will the shop do it for time and materials (which should be probably less than an hour). It's not porting. IMO the gain for $60 is worth doing it.

 

[dragondan64]

Thanks for the info and ideas. Will get the heads port matched to the intake so there will be a smooth transition and less turbulence once the motor gets going into higher rpm's. The carb cfm was chosen due to the high altitude (5000ft ASL) and the need for more air and less fuel here in the dry desert side of Colorado. But if it does cause a problem even after jetting and adjustments then I will step it up. Thanks again for taking the time to help.

 

[krazykuda]

If the 600 vac sec is not enough, it will only hurt you on the top end. I would just run it and see how it does..

 

[dragondan64]

Talked to my machinist and he will match the heads port to the intake for smooth transition into the heads port for about 1 1/2 inches into the heads. As for the gaskets he says we can make the intake gaskets from felpro gasket material and they will be perfect match also, that will be the best route to take.

 

[cudaracer]

You will never detect the minute gains. They might show up on a dyno however.