How high can the motor REV with stock internals and not worry about valve float?
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From: Canada
How high can the motor REV with stock internals and not worry about valve float?
How high can the motor rev safely using stock internals and not worrying about valve float?
For everyday extended use that is, not a one time race or experimental run.
For everyday extended use that is, not a one time race or experimental run.
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From: NAR SPEC.com, So Cal, US
Re: How high can the motor REV with stock internals and not worry about valve float? (Edwin)
9k safely daily, but whats the point.. you aren't making power that high on stock cams...
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From: Crazy Canuck, Everywhere
Re: How high can the motor REV with stock internals and not worry about valve float? (00 FBP ItR)
9k safely daily, but whats the point.. you aren't making power that high on stock cams...
Spinning the engine faster in a lower gear will keep you in the fat part of the power curve when you eventually shift. This in turn will make the car accelerate faster, which the whole point of the exercise...
You want to set your shift points so that you maximize the area under the HP vs RPM curve; trust me, this is not the case when you shift at 8400RPM..
I read somewhere on here that a team in Australia was running with a 9100RPM fuel cut-off for a considerable amount of race miles (20k+) with the stock internals. I would say that's pretty decent.
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From: T., O, Canada
Re: How high can the motor REV with stock internals and not worry about valve float? (BABY NSX)
9k safely daily, but whats the point.. you aren't making power that high on stock cams...
This is completely false... You might not be making peak numbers up there but trust me you are still making power.
Spinning the engine faster in a lower gear will keep you in the fat part of the power curve when you eventually shift. This in turn will make the car accelerate faster, which the whole point of the exercise...
You want to set your shift points so that you maximize the area under the HP vs RPM curve; trust me, this is not the case when you shift at 8400RPM..
I read somewhere on here that a team in Australia was running with a 9100RPM fuel cut-off for a considerable amount of race miles (20k+) with the stock internals. I would say that's pretty decent.
This is completely false... You might not be making peak numbers up there but trust me you are still making power.
Spinning the engine faster in a lower gear will keep you in the fat part of the power curve when you eventually shift. This in turn will make the car accelerate faster, which the whole point of the exercise...
You want to set your shift points so that you maximize the area under the HP vs RPM curve; trust me, this is not the case when you shift at 8400RPM..
I read somewhere on here that a team in Australia was running with a 9100RPM fuel cut-off for a considerable amount of race miles (20k+) with the stock internals. I would say that's pretty decent.
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From: NAR SPEC.com, So Cal, US
Re: How high can the motor REV with stock iHawaiiNKaiinI720: time was 2.06 haha from like l.a. 2 chi
9k safely daily, but whats the point.. you aren't making power that high on stock cams...
This is completely false... You might not be making peak numbers up there but trust me you are still making power.
Spinning the engine faster in a lower gear will keep you in the fat part of the power curve when you eventually shift. This in turn will make the car accelerate faster, which the whole point of the exercise...
You want to set your shift points so that you maximize the area under the HP vs RPM curve; trust me, this is not the case when you shift at 8400RPM..
I read somewhere on here that a team in Australia was running with a 9100RPM fuel cut-off for a considerable amount of race miles (20k+) with the stock internals. I would say that's pretty decent.
This is completely false... You might not be making peak numbers up there but trust me you are still making power.
Spinning the engine faster in a lower gear will keep you in the fat part of the power curve when you eventually shift. This in turn will make the car accelerate faster, which the whole point of the exercise...
You want to set your shift points so that you maximize the area under the HP vs RPM curve; trust me, this is not the case when you shift at 8400RPM..
I read somewhere on here that a team in Australia was running with a 9100RPM fuel cut-off for a considerable amount of race miles (20k+) with the stock internals. I would say that's pretty decent.
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Re: How high can the motor REV with stock iHawaiiNKaiinI720: time was 2.06 haha from like l.a. 2 chi
i know that after 8k or so... itr's powerband starts to drop.. so its not "making" anymore power, so you can rev to 9k but all it'll do is put you higher on the powerband for the next gear. s there really an advantage. Put them against each other.. 1 shifting at stock redline, one shifting at 9k... who will do better?
so saying a mere "who will do better" isnt really sufficient.
It''s really funny as I was discussing something similar with a few friends yesterday..
for JDM courses, I'd say the higher the redline the better. (less shifting)
for usdm courses i'd say it may not matter as much.
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From: Denver, CO, USA
Re: How high can the motor REV with stock iHawaiiNKaiinI720: time was 2.06 haha from like l.a. 2 chi
for JDM courses, I'd say the higher the redline the better. (less shifting)
for usdm courses i'd say it may not matter as much.
for usdm courses i'd say it may not matter as much.
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From: Charlotte
Re: How high can the motor REV with stock (Flux)
what are the differneces between a JDM and a USDM track?
I use 5th gear at 4 track I have driven (stock 4.4 final drive) (Lowes/Summit/VIR/Watkins.. maybe more)
Long straights =
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From: Crazy Canuck, Everywhere
Re: How high can the motor REV with stock (Willard)
The answer is very simple...
If you assume that the HP vs RPM curve is pretty much symmetrical about the peak then in order to maximize the area under the curve between shifts you must shift at one half the RPM difference between the two adjacent gears.
What do I mean?
Consider an engine with a symmetrical HP peak which lands at 8000RPM. Lets assume that this engine is mated to an tranny whose adjacent gears are spaced ~2000RPM apart when working at these engine speeds. With this setup you will want to shift 1000RPM after the peak occurs, 9000RPM. This will leave the engine spinning at 7000RPM after the shift ready to make another run through the curve.
The closer the ratios the tighter the shift point will be to the HP peak. But the numbers I used reflect closely what you should expect with a stock typeR with its fairly evenly spaced gearbox.
The FD has NOTHING to do with this!!!
If you assume that the HP vs RPM curve is pretty much symmetrical about the peak then in order to maximize the area under the curve between shifts you must shift at one half the RPM difference between the two adjacent gears.
What do I mean?
Consider an engine with a symmetrical HP peak which lands at 8000RPM. Lets assume that this engine is mated to an tranny whose adjacent gears are spaced ~2000RPM apart when working at these engine speeds. With this setup you will want to shift 1000RPM after the peak occurs, 9000RPM. This will leave the engine spinning at 7000RPM after the shift ready to make another run through the curve.
The closer the ratios the tighter the shift point will be to the HP peak. But the numbers I used reflect closely what you should expect with a stock typeR with its fairly evenly spaced gearbox.
The FD has NOTHING to do with this!!!
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