Short Gear Review

[SFNSXguy]

All of the above is all well and good when the two examples in question are accelerating down a straightaway. Where it all gets sticky is when the turns arrive (at a race track).

Then, what's important is WHEN the shifts must occur. If the shift must be made in the middle of a corner, that's not good. If the car runs out of rpm as a corner looms ahead (with no time to up shift), that's not good. If the car does not reach 7,900rpm at the very end of the longest straight, that's not good. If the car falls below 6,000 rpm at the apex of the slowest corner, that's not good.

The track is the tie breaker (assuming Stirling Moss is driving both cars). As Peter Cunningham pointed out to me while he was running the NSX -- he carried several transmissions with him and chose according to need.

His inventory included all the possibilities... all the mixes between R&P and gear ratios. At Sears Point he used the JDM ratios with a 4.55 R&P. He was nervous about the 4.55 R&P because he had several of them fail -- but he used it because it was the best compromise for the 11 turns found at this 2.5 mile track.

Of course we can't change gearboxes depending on where we intend to drive today, can we?

This "compromise" is why (and how) I've come to embrace the JDM/4.55 combination for road & track (that would be a catchy name for a magazine).

 

[latzke]

The 54 ft.lbs. spec is common for a stock rear end. The NSX-R spec is 110+ depending on the dif. this is done by shimming the dif clutched to "tighten up" the rear end.

I thought this was done by removing a spring plate and using the NSX-R's different (thicker) stopper plate (if you didn't remove the spring plate, extra thickness would result in too much preset torque). I suppose maybe it was an extra spring plate or two and a thinner stopper plate. I recall buying a different NSX-R stopper plate for this purpose...it's still new-in-box in the attic since the mechanic (Paul at Pikes Peak) didn't recommend increasing the preset torque and my dad went with his recommendation (car was dad's at the time).

I'm sure it can be shimmed in other ways to get to NSX-R spec...but from my research years ago I concluded that the NSX-R actually uses one different part and a different number of total parts (I'm less certain about the latter, but sure about the former) in the differential.

There is a downside to locking the wheels together more...the car is harder to turn (rear wheels have to spin at different rates when turning). Where the perfect balance is between increased resistance to spinning a single wheel when putting down the power and increased resistance to turning the car is not something I'm qualified to have an opinion on (not THAT good of a driver).

 

[Dhalsim]

This is an excellent thread. Thanks for all the great input.

So could it be summarized as follows:

Unless your tracking your car there is no need for short gears. And on some tracks its possible that the shorter gearing actually will harm your lap times instead of improve them.

 

[LJSB]

This is an excellent thread. Thanks for all the great input.

So could it be summarized as follows:

Unless your tracking your car there is no need for short gears. And on some tracks its possible that the shorter gearing actually will harm your lap times instead of improve them.

Or:

Not.:wink:

 

[goldNSX]

Some empirical evidence. Those guys who considered the short gears and finally installed them never regretted their decision in the past 6 years or so. During this time I hear plenty (not all ) of people with the long gears complaining about them. :wink:

 

[tbromley]

Some empirical evidence. Those guys who considered the short gears and finally installed them never regretted their decision in the past 6 years or so. During this time I hear plenty (not all ) of people with the long gears complaining about them. :wink:

In my year and a half here I can surely say this has been what I've heard. Must be somthing to it:wink:

 

[nsxtasy]

Some empirical evidence. Those guys who considered the short gears and finally installed them never regretted their decision in the past 6 years or so. During this time I hear plenty (not all ) of people with the long gears complaining about them. :wink:

Psychologists have a field day with stories like this. Ask people who spend money to make a change and 100 percent of them will say it's an improvement, even when it is not. They call it "cognitive dissonance" - a fancy term for saying that it's easier to talk yourself into liking something you did than to blame yourself for not liking it. :biggrin:

Again, though, there is a perception of quicker acceleration (due to the lower shift points) that is far beyond the relatively small difference in actual acceleration (to any given speed).

 

[SFNSXguy]

Psychologists have a field day with stories like this. Ask people who spend money to make a change and 100 percent of them will say it's an improvement, even when it is not. They call it "cognitive dissonance" - a fancy term for saying that it's easier to talk yourself into liking something you did than to blame yourself for not liking it. :biggrin:

I think that's more akin to "buyer's remorse"

Cognitive dissonance is an uncomfortable feeling caused by holding conflicting ideas simultaneously. The theory of cognitive dissonance proposes that people have a motivational drive to reduce dissonance. They do this by changing their attitudes, beliefs, and actions. Dissonance is also reduced by justifying, blaming, and denying. It is one of the most influential and extensively studied theories in social psychology.

If you're one of those folks that think the JDM gears are better, it must just be a figment of your (our) imagination.

 

[goldNSX]

Psychologists have a field day with stories like this. Ask people who spend money to make a change and 100 percent of them will say it's an improvement, even when it is not. They call it "cognitive dissonance" - a fancy term for saying that it's easier to talk yourself into liking something you did than to blame yourself for not liking it. :biggrin:

Yes, it's omnipotent here in the forum and in circumstances with just with a massively higher money-wise impact without going into too much details.

It can be read in all of my posts on the short gears that the car gains more flexibility not just more g's in the lower gears. I never said it benefits to every driver.

 

[nsxtasy]

The other thing to realize is that changes in gearing don't affect acceleration all that much, either way. You'll get far greater improvement from modifications which offer even relatively modest increases in horsepower or modest decreases in weight.

 

[goldNSX]

The other thing to realize is that changes in gearing don't affect acceleration all that much, either way. You'll get far greater improvement from modifications which offer even relatively modest increases in horsepower or modest decreases in weight.

Horsepower yes, modest weight loss no according to the FAQ.

 

[LJSB]

Psychologists have a field day with stories like this. Ask people who spend money to make a change and 100 percent of them will say it's an improvement, even when it is not. They call it "cognitive dissonance" - a fancy term for saying that it's easier to talk yourself into liking something you did than to blame yourself for not liking it. :biggrin:

Again, though, there is a perception of quicker acceleration (due to the lower shift points) that is far beyond the relatively small difference in actual acceleration (to any given speed).

What Ken's saying is that if you disagree with him you're nuts.:biggrin:

 

[Larry Bastanza]

I thought this was done by removing a spring plate and using the NSX-R's different (thicker) stopper plate (if you didn't remove the spring plate, extra thickness would result in too much preset torque). I suppose maybe it was an extra spring plate or two and a thinner stopper plate. I recall buying a different NSX-R stopper plate for this purpose.

Yes, you are correct and that is exactly what I did. I used the word "shimming" to describe the extra shim and stopper plate.

Regards,
LarryB

 

[SFNSXguy]

What Ken's saying is that if you disagree with him you're nuts.:biggrin:

No comment.

 

[goldNSX]

What Ken's saying is that if you disagree with him you're nuts.:biggrin:

Not yet - but the short gears are driving me nuts - they are so good. :tongue:

The Type R diff parts consists of these two and a third part. Anyone know it's number?

 

[LJSB]

If you're one of those folks that think the JDM gears are better, it must just be a figment of your (our) imagination.

A Fig Newton of my imagination: Fiber makes you FASTER.

 

[tbromley]

Psychologists have a field day with stories like this. Ask people who spend money to make a change and 100 percent of them will say it's an improvement, even when it is not. They call it "cognitive dissonance" - a fancy term for saying that it's easier to talk yourself into liking something you did than to blame yourself for not liking it. :biggrin:

Again, though, there is a perception of quicker acceleration (due to the lower shift points) that is far beyond the relatively small difference in actual acceleration (to any given speed).

Now - I really don't know that much about this because I haven't driven a car with shorties -but Ken your argument can go both ways it seems to me.

You may be arguing against the shorties to rationalize your own "dissonence" cause you don't want to fork out the bucks. Is it worth it - that's kind of the question I hear - the undercurrent- the cost to benefit ratio. It may not make economic sense but then spending lots of money on car mods that you'll never recoup - well is that sensible? No most likely not in that argument - but if you like it and it is faster I mean the numbers show it - they didn't create these gear sets cause they don't affect the driving MOST do on most tracks cause they don't need em, ie just for the hell of it. Maybe on your track and maybe in your mind it doesn't make sense to you - and you have gone to great lenths to try and prove that - to yourself - cause many here obviously have done it and extoll the virtues just like you do not. So all this paper argument stuff and some one track when you can shift into 5th for 3 to 4 seconds being the rule of "thumb" - maybe for you it's right - for others it's not.

I think you gotta be a little more flexible in your position. Otherwise why do you think that Honda came up with it???? Doesn't that have to make you wonder just a little - they didn't do it for their health.

My 1 cents worth of my own brand of dissonence.

 

[nsxtasy]

Horsepower yes, modest weight loss no according to the FAQ.

Wrong. Either horsepower or weight loss will give better acceleration than gearing changes. Here are the numbers.

1/4 mile acceleration in seconds for a '91 NSX:
stock gears - 13.67 seconds
short gears - 13.56 seconds
stock with +15 hp - 13.35 seconds
stock with -100 lb - 13.51 seconds

0-150 acceleration in seconds for a '91 NSX:
stock gears - 37.78 seconds
short gears - 41.06 seconds
stock with +15 hp - 33.25 seconds
stock with -100 lb - 36.62 seconds

You may be arguing against the shorties to rationalize your own "dissonence" cause you don't want to fork out the bucks.

Not true. I use my car on racetracks where roughly 65-80 mph is the "sweet spot", the speeds that are often used through the corners and long stretches of the track (such as Mid-Ohio all the way from the end of the back straight to the chute). An NSX with stock gears can use second gear in those sections and is simply faster than an NSX with short gears which is stuck using third.

I think you gotta be a little more flexible in your position.

Oh please, get serious. As I have said, for general street use, like if you're concerned about speed "off the line" if you're trying to beat someone away from a stoplight, the short gears are faster. And, they give the additional perception of being faster, beyond the actual speed differences. But the stock gears are faster above 70 mph, so if that's where you want quicker acceleration, you're better off sticking with the closer-ratio stock gears rather than the wider-spaced short gears. It just depends on where you want the benefit, below 70 mph or above 70 mph.

I think those who claim that the short gears are ALWAYS faster are the ones who need to be a little more flexible in their position. Because they are NOT always faster.

 

[tbromley]

Wrong. Either horsepower or weight loss will give better acceleration than gearing changes. Here are the numbers.

1/4 mile acceleration in seconds for a '91 NSX:
stock gears - 13.67 seconds
short gears - 13.56 seconds
stock with +15 hp - 13.35 seconds
stock with -100 lb - 13.51 seconds

0-150 acceleration in seconds for a '91 NSX:
stock gears - 37.78 seconds
short gears - 41.06 seconds
stock with +15 hp - 33.25 seconds
stock with -100 lb - 36.62 seconds


Not true. I use my car on racetracks where roughly 65-80 mph is the "sweet spot", the speeds that are often used through the corners and long stretches of the track (such as Mid-Ohio all the way from the end of the back straight to the chute). An NSX with stock gears can use second gear in those sections and is simply faster than an NSX with short gears which is stuck using third.


Oh please, get serious. As I have said, for general street use, like if you're concerned about speed "off the line" if you're trying to beat someone away from a stoplight, the short gears are faster. And, they give the additional perception of being faster, beyond the actual speed differences. But the stock gears are faster above 70 mph, so if that's where you want quicker acceleration, you're better off sticking with the closer-ratio stock gears rather than the wider-spaced short gears. It just depends on where you want the benefit, below 70 mph or above 70 mph.

I think those who claim that the short gears are ALWAYS faster are the ones who need to be a little more flexible in their position. Because they are NOT always faster.

Good response Ken.- very detailed as ususal! I would say most of us street drivers would enjoy the short gears - not for stop light challenges but most of our driving is surely below 70 in our canyon carving areas. I would say that the predominance of owners never see a track. Just a guess.

You mention - weight and hp gains- lot of us could do all three -then we'd really see an improvement - although I can't figure out where you get a 100 lb reduction - the spare tire is most likely only 25 lbs or so. Headers - well most do that in the early ones - where else would you get modest hp gains? Just curious. Obviously the easiest way to be assured of quicker times is to personally loose weight :biggrin: and put in shorties, especially if you already have headers like me.

Otherwise on the track - most would see a bigger difference in their track times by taking driving lessons! Proficiency behind the wheel - there is no substitute!

 

[nsxtasy]

where else would you get modest hp gains?

Not necessarily hp gains, but you can see weight reduction numbers here.

 

[goldNSX]

Wrong. Either horsepower or weight loss will give better acceleration than gearing changes.

I was referring to your statement about 'modest weight-saving'. Modest weight-savings won't help you much. -100 lbs is quite much for a car where every part has been put on a scale. Of course, on a standard, absolutely stock NSX, you can find this weight but as soon as you've thrown the spare time, the trunk tools and maybe some little things out of the car (been there - done that), it gets difficult/very expensive. So moddest weight-saving is far less effective in straight-line-acceleration that adding hp. Adding 20 hp is no big deal on a stock NSX.

You proof it with an example with your numbers. :wink: Therefore, I'm not wrong.

 

[nsxtasy]

Fair enough. :smile:

 

[SFNSXguy]

Bear in mind that most of the "numbers" bandied about on this issue are all "calculated" numbers. When it comes to a car on a road I would trust "empirical" data quite a bit more (based on my experience).

When running cars with easily-exchanged gears (Hewland, etc.) we would often used computer data to select ratios before going to a new track -- to save some time, always useful when learning a new circuit.

80% of the time two or more ratios would need to be changed before I was happy. This is due to the way a road twists and turns, rises and falls -- things the computer which only has two dimensional data and can't possibly be expected to understand/compute things like traction, wind and its direction, location of berms, co-efficient of friction of a given rubber compound etc.

So one can quote "numbers" until they're blue in the face -- the proof is in the lap times after sufficient practice time. And, it is my experience that MOST of the tracks I've experienced would best be served by the JDM gears with a 4.55 R&P.

It's a complete no-brainer that this combination is the best for the street, ERGO why have several trannys for track/street?

Now I understand that keN has "driven" on more tracks than Ayrton, and simply driving around a track is somewhat different than DRIVING around a track. With the OEM USA tranny you can drive around every track in the country. Hell, if you wanted to you could do them all in just 3rd gear (as keN suggested to a student in Phoenix). If you want to do more than that, I recommend the JDM/4.55 version.

(God I hope this controversy ends soon, I'm getting carpel tunnel.)

 

[nsxtasy]

Bear in mind that most of the "numbers" bandied about on this issue are all "calculated" numbers. When it comes to a car on a road I would trust "empirical" data quite a bit more (based on my experience).

Me too. And I know that second gear gives you much better acceleration at tracks with a lot of corner-to-corner flow, like Mid-Ohio, whereas with the short gears it's virtually useless at many tracks.

So one can quote "numbers" until they're blue in the face -- the proof is in the lap times after sufficient practice time. And, it is my experience that MOST of the tracks I've experienced would best be served by the JDM gears with a 4.55 R&P.

And it is my experience that MOST of the tracks I've experienced would best be served by the USIM stock gears with the USIM stock 4.062 R&P.

(endless tacky insults deleted - I used to think Harry was a reasonably classy guy, but not since his juvenile phallic references and other similarly puerile quips in these topics)

Hell, if you wanted to you could do them all in just 3rd gear (as keN suggested to a student in Phoenix).

That depends on the track and the student. Doing an entire track in third gear is often a good recommendation when a novice student is not experienced at shifting and finds it distracting at his first track event. Nice job taking that out of context, Harry!

If you have enough experience to do a lot of shifting to take advantage of all the gears that the NSX has to offer, with the best rate of acceleration through the turns and down the straights, I strongly recommend the stock USIM gears with their closer spacing for gears 2-5, rather than the short gears with the closer spacing of gears 1-2. It's the same reason the six-speed is superior to the five-speed; the stock five-speed gives you four closely-spaced gears to use on the track, rather than the three wider-spaced gears you're limited to with the short gears. More gears, with closer spacing, means that you can take better advantage of gearing in maximizing your rate of acceleration.

(God I hope this controversy ends soon, I'm getting carpel tunnel.)

You wouldn't, if you didn't insist on always having the last word!

 

[SFNSXguy]

Hey keN

Please list a couple of the "endless tacky insults" that you referred to, and at least one of the "juvenile phallic references" and a couple of the "similarly puerile (good use of your vocabulary, by the way) quips" in these topics -- I must have missed them! Please save readers the trouble of searching.

...and as to "the last word," hmmmm.


P.S. "Students" come to learn, just sayin'.