And what sort of internal mods do you use? Plus, when you do that do you shift right at the max redline or about 200 ahead?

 

if you aren't making power there, no reason to change anything. A stock 5th en lude peaks power at 7000 rpms...not much reason going past 7200-7400 unless you are in first gear and want to stay in VTEC.

If you have the mods that actually need a higher rev limit...(BTW I was running a fully built motor 12:1 and Custom Crower Drag cams and still didn't need a higher fuel cut power peaked at 7600) you need better valvseprings and retainers. A superstrong T-belt is also a good idea. Prodrive oil pump gear...balanced rotating assembly...

 

Peak power at 7600 doesn't mean you should shift at 7600 for best acceleration.

Adi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">A stock 5th en lude peaks power at 7000 rpms...not much reason going past 7200-7400 unless you are in first gear and want to stay in VTEC.
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Not true IMO. Try to calculate torque on the wheels in every gear. You will see, that shifting 1-2, 2-3 and even 3-4 should be shifted at the highest RPM possible. If you shift any time sooner, you will loose torque on the wheels in comparsion to the lower gear at same speed.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Quick99Si &raquo;</TD></TR><TR><TD CLASS="quote">Peak power at 7600 doesn't mean you should shift at 7600 for best acceleration.

Adi</TD></TR></TABLE>

stock fuel cut was 7900, my rev limit was 8500 but I barely ever saw 8200. minimal increase.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by petrv &raquo;</TD></TR><TR><TD CLASS="quote">
Not true IMO. Try to calculate torque on the wheels in every gear. You will see, that shifting 1-2, 2-3 and even 3-4 should be shifted at the highest RPM possible. If you shift any time sooner, you will loose torque on the wheels in comparsion to the lower gear at same speed.
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I have no idea what you are trying to say. Cars put relatively the same torque to the wheels no matter what gear you're in. Just the accuracy of the equipment changes. Your graph is horribly wrong

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">
I have no idea what you are trying to say. Cars put relatively the same torque to the wheels no matter what gear you're in. Just the accuracy of the equipment changes. Your graph is horribly wrong</TD></TR></TABLE>
Do you think that there is same torque on the wheels in 1st gear@5000rpm and in 5th gear@5000rpm? I don't think so.

The graph is very simple - it shows that when you are ate 7400rmp@1st gear, you have 2100Nm on the wheels. When you shift to 2nd at this time, you get to let's say 5500rpm@2nd gear, so the torque on the whhels is only 1400Nm. This means that it would be better to rev the 1st gear to about 8000rpm and then shift to 2nd. This is similiar to other gears.

I know, this graph is not very good fro calculating best shitfing points, but you can see some basic things there. I created this graph for some other purpose.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by petrv &raquo;</TD></TR><TR><TD CLASS="quote">
Do you think that there is same torque on the wheels in 1st gear@5000rpm and in 5th gear@5000rpm? I don't think so.</TD></TR></TABLE>

I know what you are saying but your graph doesn't show it well. I have a graph that I will post later today

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by satan_srv &raquo;</TD></TR><TR><TD CLASS="quote">
I know what you are saying but your graph doesn't show it well. I have a graph that I will post later today</TD></TR></TABLE>
OK . The torque on the wheels is of course not the same in 1st and 5th gear at 5000rpm, that's why 1st gear at 5000rpm will push you more than 5th gear at 5000rpm. Power is the same, not the torque.

 

I did some calculations of the numbers too and your numbers look too high, I'm not really sure what numbers you used for calculating torque, also there will be some drivetrain losses. The graphs look relatively accurate in shape and as long as your engine is making more than 95 ft-lbs of torque in 1st gear it is still putting more torque to the wheels than peak torque in 2nd gear

 

You're confusing torque with forward thrust. Torque as measured is corrected for gearing, forward thrust isn't.

Adi

 

I'm pretty scared taking my car to 8000 rpm and thats with a upgraded valvetrain and Crower Stage 2 cams.

when the motor was stock i can feel that the motor was not producing any more power after 7000 rpm, so i shifted around 7200 to 7400 rpm

 

my motor is stock and i shift it right at 8k, and thats on an Autometer tach, not a stock one...my times are much faster...if i shift at 7400-7600...id lose 3 tenths in the 1/4 at least....im using a p28 GSR mugen ECU....btw. ive never had any problems shifting that high...my rev limit is higher although i never take it higher..on purpose anyways....2 years and still perfect compression ect...i believe tking it a little past the peak power is better for acceleration, because you may be losing some power , but it wont be as much when you consider the 500 or so RPMs higher youll land in the rev range after each shift...just my 2 cents, but it works for me

 

Exactly.

 

I shift at about 8.. (usually about 7800-7900).

It runs quicker, and keeps me deeper into VTEC.

I sometimes worry about the condition of the motor from doing this though (They made a redline for a reason...).

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99BlackSH &raquo;</TD></TR><TR><TD CLASS="quote">I shift at about 8.. (usually about 7800-7900).

It runs quicker, and keeps me deeper into VTEC.

I sometimes worry about the condition of the motor from doing this though (They made a redline for a reason...).</TD></TR></TABLE>

you know what they say about rules, redlines are made to be broken

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Speedra500 &raquo;</TD></TR><TR><TD CLASS="quote">

you know what they say about rules, redlines are made to be broken </TD></TR></TABLE>

Actually, I think it's "motors are built to be broken...."

 

the chances are if mine did break.. It'd give me a reason to build it up before I get a turbo kit..

lol soo I'll keep revving to 8