Chamber Mods vs Gains

[skinny z]

My peanut port heads have "big lazy chambers" and with only 8:1 compression I could only manage to run 11.16@118mph. I know that's pretty poor from a performance stand point.

Doesn't this beg the question of what the difference might be with a "small efficient chamber" and 10.5:1?

Isn't your Vortec 406 equally impressive?

[1980RS]

My peanut port heads have "big lazy chambers" and with only 8:1 compression I could only manage to run 11.16@118mph. I know that's pretty poor from a performance stand point.

Doesn't this beg the question of what the difference might be with a "small efficient chamber" and 10.5:1?

Isn't your Vortec 406 equally impressive?

Yes but the compression on the 406 is 11:1 and the 461 Peanut port engine was 8:1, my problem is that I am not sure if I put my 12:1 Venoilia pistons in the 461 that it would make a huge power difference with the super small port of these heads.

[panic]

An old rule: "if it doesn't breathe well, compress the h*** out what you can get".

[skinny z]

An old rule: "if it doesn't breathe well, compress the h*** out what you can get".

Similarly, with a lack of compression, I was advised that "I better be damn sure I fill it!" Quote David Vizard.

[juuhanaa]

Overlap triangle limited and driven by exhaust: Flows across... duration... exhaust velocity? How much is needed to sign the intake in, and what is the best way to produce it in the engine we are working on?

Although the principles (what principles i dont know ) could be applied to different types of engines, but when we have an engine with a redline of 8000 rpm and only ,02 inches of valve lift at TDC, now all the sudden flows across the chamber and timing becomes sensitive. Btw first response from this site to my example engine was: Do not be surprised if it turns out to be very "reverse pattern" cam events. Now a more recent comment from the same guy: It still all boils down to valve events with whatever you are trying to accomplish.

..Higher velocity in the funnel shaped intake port combined with a later IVO sounds like a plan to my combo, and i feel this direction is more clear after measuring such things what its worth i dont know, but who cares about low lift numbers or port energy, let alone is willing to share them



-juhana