I'm just wondering what peoples worst gear is. Talking about USDM H22's and trannies. It seems to me that my worst gear is 4th. It seems like I have to shift at only around 6500rpms or so. To me it *seems faster* if I shift early rather than taking to 7000rpms or so where I should be making peak power right. I got the usual ricer mods I/H/E and am just wondering if anyone else has a weak 4th gear cuz my smack seems to fall on it's face at aroudn 6500

 

second gear is my worst, it falls to 1500rpm.... but you know that could be due to a blown tranny that has been driven for a entire season lol

 

Reverse, that **** just doesnt pull like it use to.....

 

id just like to know why IHE are considered ricer mods.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMhondalude22 &raquo;</TD></TR><TR><TD CLASS="quote">id just like to know why IHE are considered ricer mods. </TD></TR></TABLE>

it's all about the quality of your mods.

 

I used to have trouble missing 4th but i finally got it down packed....I also power shift by keeping in the gas, which was another reason it sucked when i missed 4th. Powershifting helped me stay in the heart of my power band.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94Vtecluder &raquo;</TD></TR><TR><TD CLASS="quote">I'm just wondering what peoples worst gear is. Talking about USDM H22's and trannies. It seems to me that my worst gear is 4th. It seems like I have to shift at only around 6500rpms or so. To me it *seems faster* if I shift early rather than taking to 7000rpms or so where I should be making peak power right. I got the usual ricer mods I/H/E and am just wondering if anyone else has a weak 4th gear cuz my smack seems to fall on it's face at aroudn 6500</TD></TR></TABLE>

That's probably because a stockish H22's torque starts to drop off at a decent rate around 6500rpm.

The car is still geared pretty well. It will be faster to take it to redline (and beyond to some degree) for every gear.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chuckles99SH &raquo;</TD></TR><TR><TD CLASS="quote">Reverse, that **** just doesnt pull like it use to.....</TD></TR></TABLE>

my reverse pulls pretty goood, especially in vtec.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Eddiebx &raquo;</TD></TR><TR><TD CLASS="quote">my reverse pulls pretty goood, especially in vtec.</TD></TR></TABLE>


and it sounds like a loud *** remote control car on angel dust

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chuckles99SH &raquo;</TD></TR><TR><TD CLASS="quote">Reverse, that **** just doesnt pull like it use to.....</TD></TR></TABLE>

LMFAO!! Easy Paul Walker

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JDMhondalude22 &raquo;</TD></TR><TR><TD CLASS="quote">id just like to know why IHE are considered ricer mods. </TD></TR></TABLE>

That was just a joke.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by A Blue Lude &raquo;</TD></TR><TR><TD CLASS="quote">That's probably because a stockish H22's torque starts to drop off at a decent rate around 6500rpm.

The car is still geared pretty well. It will be faster to take it to redline (and beyond to some degree) for every gear.</TD></TR></TABLE>

True. I guess what I'm saying is it *feels* like it's pulling harder when shift to 5th earlier than it does taking it to redline in 4th. Most H22's make peak power at ~7200rpms or right so it should be the other way around.

 

5th

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 94Vtecluder &raquo;</TD></TR><TR><TD CLASS="quote">True. I guess what I'm saying is it *feels* like it's pulling harder when shift to 5th earlier than it does taking it to redline in 4th. Most H22's make peak power at ~7200rpms or right so it should be the other way around.</TD></TR></TABLE>

Well, peak power isn't that important for determining when you should shift.

Graphs &gt; Butt dynos



And this is a Prelude shifting at 7500rpm. Notice how forward progress is only hindered when upshifting.

 

^well of course foward progress is hindered.....becasue of gearing...

and Peak Power (torque) has EVERYTHING to do with where you should shift.....

this is my dyno from a while back...before this i always shifted at 6k or so....now i shift just after 5500.....there is no reason for me to shift at any higher of an RPM

 

i dont have my h22 in but my worst gear in my white lude would be 1st symptoms of a slipping clutch are the cause of that

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 95greenlude &raquo;</TD></TR><TR><TD CLASS="quote">and Peak Power (torque) has EVERYTHING to do with where you should shift.....</TD></TR></TABLE>

Feel free to explain why.

I'll suggest that the only thing that matters is comparing the torque to the wheel in the current gear to the torque to the wheel is available in the next gear. If torque has fallen off so much that upshifting to the stiffer ratio still nets you the same or more torque, then it is indeed time to shift.

Given that a dyno doesn't talk about the key aspect of this, gear ratios, talking about "peak power" being so important is BS.

This graph compares the results of a 5500rpm shiftpoint vs 6500rpm shift point. And guess what, tells me you'd be better off shifting at 6500, even from 4th to 5th. Yes, I made it out of your convenient dyno. Even shifting at the end of your dyno (which is maybe a 100rpm shy of 6500 in reality, but eh) you never gain torque shifting to the next gear.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by A Blue Lude &raquo;</TD></TR><TR><TD CLASS="quote">That's probably because a stockish H22's torque starts to drop off at a decent rate around 6500rpm.

The car is still geared pretty well. It will be faster to take it to redline (and beyond to some degree) for every gear.</TD></TR></TABLE>


True but I wouldn't figure torque to fiqure in that much at that speed. Peraps I was wrong though. I figured moving momentum is easlier to move that moving momentum.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by A Blue Lude &raquo;</TD></TR><TR><TD CLASS="quote">Well, peak power isn't that important for determining when you should shift.

Graphs &gt; Butt dynos



And this is a Prelude shifting at 7500rpm. Notice how forward progress is only hindered when upshifting.</TD></TR></TABLE>

That graph looks like homie is shifting prior to vtak y0. It should kick in every 20 mph , 40,60, 80 etc. That graph looks like homeboy is shifting way to early. That's a horrible novice gear graph. Home boy falls outta vtec from first to seond shift. I never fall outta vtak y0


Modified by 94Vtecluder at 12:45 PM 10/21/2006

 

my worst gear is totally 4th....it never goes in and sometimes it pops out...

 

guys this argument is retarded

you shift at peak hp and aim to land at peak tq, that is a great rule of thumb, esp for our cars, knowing that tq is most likely gonna peak somewhere around 5500 and peak hp is gonna be more like 7000, our ratios are perfect to land in that range

for the h23 guys just subtract about 1000 rpm from that

a blue lude, to make those graphs what is your exact calculation....like the formula to get from hp and tq to thrust at the wheel....gearing, wheel size, etc must be accounted for....but yea whats the formula??

 

Shifting at peak HP is going to make you slower, as documented. I'm sure there are certain vehicles with certain gear ratios where you will want to shift at peak HP, though.

Formula is...

(Engine Torque * (gear ratio * final drive ratio)) / (Wheel rolling radius) = lbs of thrust at the wheel at a certain engine RPM.
Then some legwork to get vehicle speed at that RPM and gear ratio and some graphing stuff. I won't pretend to have come up with the formulas.

It's not perfect since it gives torque data for every few mph, and not every single mph from 0-150, but it's pretty good.

 

so hp has no effect on that graph at all huh.....well that is certainly something to think about....

anyone have any ideas on how hp could be calculated in??

wouldnt hp have something to do with it along the lines of torque applied per second?

 

HP certainly has an effect on the graphs that I've been posting.

Here's that guys I/H/E H23 vs a stock H22, (H23 tranny vs 5g H22 tranny, but they are very similar)

Similar torque not similar HP. But torque doesn't really matter that much. HP matters. The H23's greater low end power only shows up at low RPMs in 1st gear, and the big big gap between 1st and 2nd where RPMs actually drop to a pretty low range. From VTEC and on in 1st gear the H22 is a faster engine. Or somesuch.

Disclamer: These are two different dynos, etc, etc, so don't take this as gospel in the H22/H23 debate. Plus the torque multiplication in the lower gears makes small differences really stand out.



edit: to illustrate the advantage of HP, maybe this will help.

I/H/E H23 vs H22 vs "special" H22.

The "special" H22 makes only 143lb/ft peak torque. It also makes that peak at over 17,000 rpm, and holds enough of that torque to make about 700hp @ 30,000 rpm. Through a H22 tranny, it can do over 150mph in first gear.
It could also be geared down to have a 150mph top speed in 5th gear and make lots more torque everywhere.






Modified by A Blue Lude at 12:39 PM 10/23/2006

 

Never had a problem with 4th until this weekend during my first HPDE. Saturday I had a problem getting into 4th on a few laps then redline shifted 3rd to 2nd on the main straight at Rockingham! Glad I never sidestep the clutch so when the rpms went through the roof I got back into the clutch before the motor went into self distruct mode. From then on I was great-granny shifting into 4th to make sure there were no 10,000rpm encores! Wj

 

where the heck is hp in that equation??

or am I missing something here?

are you using rpm and tq numbers to "represent" hp on that graph, saying that higher tq at higher rpm means you have more hp? (from a math standpoint this is obvious)

 

I'm not trying to represent HP, I'm trying to represent the acceleration of a car (independent of such things as aero and mechanical resistance, traction, etc). It will definitely need to be broken down further to really e-race two cars, but I've fooled around with it to look at some real-life comparisons and some hypothetical ones (like does torque matter...at all?).
And while it's not the best system for determining shift points, it's easy enough to use it to see if you're shifting too early, or too late, or on time. Which is why it showed up in this thread.

HP isn't directly in any of the calculations.