BB Chev heads intake and cam questions

Alan Roehrich · 06-03-2015, 06:41 PM

This thread should probably be in the tech section.

A 359 is a rectangle port intake. These days, with the number of quality oval port intake manifolds, there is no real reason to use a rectangle port intake with oval port heads. An Edelbrock Performer RPM Oval Port Air Gap intake would be a good choice.

Those heads are fine. They will likely be closer to 101 or 102cc, if not a little bigger. You could upgrade to 2.19" intake valves, with some bowl blending and decent porting if you wanted, for most street cars, putting the 1.88" exhaust valves in often isn't worth it, given the small bore and closed chamber. In fact, the 1.725" valve and smaller port usually helps velocity, and there are a lot of Stock Eliminator cars making 600+ HP with 1.725" exhaust valves.

Provided you have the right converter, I'd probably be looking at Comp Extreme lobes, and a custom grind 224 to 232 @ 0.050" on the intake, and about 8 degrees more duration on the exhaust than the intake, on a 108 or 110 LSA. You can run solid, hydraulic, solid roller, or hydraulic roller.

It's not a problem to get over 500HP out of a 402 like that on pump gas, even with a hydraulic flat tappet cam.

06-03-2015, 06:41 PM	#3
Alan Roehrich Veteran Member Join Date: May 2006 Location: Murfreesboro TN Posts: 5,107 Likes: 1,564 Liked 1,795 Times in 409 Posts	Re: BB Chev heads intake and cam questions This thread should probably be in the tech section. A 359 is a rectangle port intake. These days, with the number of quality oval port intake manifolds, there is no real reason to use a rectangle port intake with oval port heads. An Edelbrock Performer RPM Oval Port Air Gap intake would be a good choice. Those heads are fine. They will likely be closer to 101 or 102cc, if not a little bigger. You could upgrade to 2.19" intake valves, with some bowl blending and decent porting if you wanted, for most street cars, putting the 1.88" exhaust valves in often isn't worth it, given the small bore and closed chamber. In fact, the 1.725" valve and smaller port usually helps velocity, and there are a lot of Stock Eliminator cars making 600+ HP with 1.725" exhaust valves. Provided you have the right converter, I'd probably be looking at Comp Extreme lobes, and a custom grind 224 to 232 @ 0.050" on the intake, and about 8 degrees more duration on the exhaust than the intake, on a 108 or 110 LSA. You can run solid, hydraulic, solid roller, or hydraulic roller. It's not a problem to get over 500HP out of a 402 like that on pump gas, even with a hydraulic flat tappet cam. __________________ Alan Roehrich 212A G/S