3 valves per cylinder?
Record Breaker
Joined: Feb 2005
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RE: 3 valves per cylinder?
They don't do it because they don't need it. They also wouldn't be able to fit a 3rd valve, assumabley an intake valve ala Ford. If they could fit it in there, I'd believe they'd be burning up in no time as there is not enough material up there to act as a heat sink. It is all about flow and not how many valves there are.
I'd be curious to know what the flow rate of Dodge's heads are compared to the competition.
I'd be curious to know what the flow rate of Dodge's heads are compared to the competition.
Captain
Joined: Apr 2005
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RE: 3 valves per cylinder?
Osteodoc:
I just saw that the 5.7 crate hemis (I'd assume with the same heads as production installed ones) have intake flow rates of 210@.300 lift and 265@.500 lift. The magazine didn't note if these data were at 25 or 28 inches of water, but the correction factor either way is small enough that it wouldn't make much difference. As I recall, these flow figures are similar to other hipo heads of other configurations. However, one of the often overlooked aspects of the modern hemi is the benefit of dual plugs in terms of controlling burn.
It would seem to me that these flow rates would be quite adequate for almost any rational engine usage. For comparison, the 5.7 hemi heads outflow the very best we can produce with our antique-engined car in my avatar; yet we still make 1100hp out of 299c.i. (at 40 pounds of turbo boost)! So, I'm thinking that stock 5.7 hemi heads should be capable of 1000hp with perhaps 23-25 pounds of boost. Not too shabby!
All the best.
I just saw that the 5.7 crate hemis (I'd assume with the same heads as production installed ones) have intake flow rates of 210@.300 lift and 265@.500 lift. The magazine didn't note if these data were at 25 or 28 inches of water, but the correction factor either way is small enough that it wouldn't make much difference. As I recall, these flow figures are similar to other hipo heads of other configurations. However, one of the often overlooked aspects of the modern hemi is the benefit of dual plugs in terms of controlling burn.
It would seem to me that these flow rates would be quite adequate for almost any rational engine usage. For comparison, the 5.7 hemi heads outflow the very best we can produce with our antique-engined car in my avatar; yet we still make 1100hp out of 299c.i. (at 40 pounds of turbo boost)! So, I'm thinking that stock 5.7 hemi heads should be capable of 1000hp with perhaps 23-25 pounds of boost. Not too shabby!
All the best.
Record Breaker
Joined: Feb 2005
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RE: 3 valves per cylinder?
ORIGINAL: Avanti
Osteodoc:
I just saw that the 5.7 crate hemis (I'd assume with the same heads as production installed ones) have intake flow rates of 210@.300 lift and 265@.500 lift. The magazine didn't note if these data were at 25 or 28 inches of water, but the correction factor either way is small enough that it wouldn't make much difference. As I recall, these flow figures are similar to other hipo heads of other configurations. However, one of the often overlooked aspects of the modern hemi is the benefit of dual plugs in terms of controlling burn.
It would seem to me that these flow rates would be quite adequate for almost any rational engine usage. For comparison, the 5.7 hemi heads outflow the very best we can produce with our antique-engined car in my avatar; yet we still make 1100hp out of 299c.i. (at 40 pounds of turbo boost)! So, I'm thinking that stock 5.7 hemi heads should be capable of 1000hp with perhaps 23-25 pounds of boost. Not too shabby!
All the best.
Osteodoc:
I just saw that the 5.7 crate hemis (I'd assume with the same heads as production installed ones) have intake flow rates of 210@.300 lift and 265@.500 lift. The magazine didn't note if these data were at 25 or 28 inches of water, but the correction factor either way is small enough that it wouldn't make much difference. As I recall, these flow figures are similar to other hipo heads of other configurations. However, one of the often overlooked aspects of the modern hemi is the benefit of dual plugs in terms of controlling burn.
It would seem to me that these flow rates would be quite adequate for almost any rational engine usage. For comparison, the 5.7 hemi heads outflow the very best we can produce with our antique-engined car in my avatar; yet we still make 1100hp out of 299c.i. (at 40 pounds of turbo boost)! So, I'm thinking that stock 5.7 hemi heads should be capable of 1000hp with perhaps 23-25 pounds of boost. Not too shabby!
All the best.
Veteran
Joined: Mar 2005
Posts: 255
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RE: 3 valves per cylinder?
You guys STILL amaze this old guy...... very impressive, and by the way, I WANT the 1000HP hemi in my truck, LOL...............that'll make my blood flow.......................................GUIDO
