couple questions

[hayabusa1285]

got a couple questions

first when swaping my drive shadts last night me and friend were thinking of ways increase power through the drive(or i guess lose of it). and one thinking we were debating on was makiing the moutns that the diff are mounted too strong by filling them in with something like window sealant. my thoughts on this was it would wear out the diff quick and really would gain much in the area of power. thoughts

also i know the 00-01 run really rich but i just had someone else tell emt hat they run lean while in vtec something like 17:1 with a cat on. which is true?

and last one how heavy is the stock fly wheel in a AP1

[JonBoy]

Window sealant is nowhere near as strong as steel. All you would do is gum things up. You need to allow for movement/play in the shafts and you'd actually end up increasing friction, reducing power to the wheels.

There's a fine line between too loose and too tight and if there are bearings involved, you really don't want to try and "add" anything to the system. Everything you need to do to reduce play/slop can be done within the parameters of the stock setup.

To reduce driveline losses, you could go to straight cut gears (very loud but more efficient and stronger, so you can make them smaller/lighter as well!), carbon fiber driveshaft (less weight), a lighter flywheel (less weight), and a grabbier clutch (more friction to reduce slip losses).

[hayabusa1285]

Window sealant is nowhere near as strong as steel. All you would do is gum things up. You need to allow for movement/play in the shafts and you'd actually end up increasing friction, reducing power to the wheels.

There's a fine line between too loose and too tight and if there are bearings involved, you really don't want to try and "add" anything to the system. Everything you need to do to reduce play/slop can be done within the parameters of the stock setup.

To reduce driveline losses, you could go to straight cut gears (very loud but more efficient and stronger, so you can make them smaller/lighter as well!), carbon fiber driveshaft (less weight), a lighter flywheel (less weight), and a grabbier clutch (more friction to reduce slip losses).

see i'm with you i dont feel filling in the mounts would help anything but just wear the gear out quicker. carbon fiber did come up in the discussion, a lil pricey really but i would think it would have the best gain and still keep from making the car vibrating to much

[repiv]

makiing the moutns that the diff are mounted too strong
I'm not sure I'm getting the true idea of this statement, so I'm guessing here. There already exists "solid" diff mounts:
http://www.aj-racing.com/catalog/product.php?productid=1273
Unless you are in a racing application or are in the business of racing and have the budget to replace and rebuild stuff, this would be very ill-advised. Things on this car are designed the way they are to maximize track performance while giving it a modicum of streetability, drivability and longevity. Changing the car in even one area, strips away some of the attributes of another.
For example, we always get discussions of engine torque dampers from time to time and the general consensus is that these are more for show than anything else. Perhaps on a pure track car, you would find a small benefit from limiting the normal movement of the engine, but for a daily driven street car, this would be detrimental to the longevity of the car as a whole and the small difference they make, tend to be quite minor and hard to perceive by the vast majority of S2000 drivers.
All cars have components that normally move and vibrate. If we didn't allow for some "controlled" movement, these motions and vibrations would get transmitted to things that would simply wear out much sooner than desired. This is why we have fluid filled engine and rear diff mounts and rubber tranny mounts. Why do we not have solid mounts where we have rubber or neoprene suspension bushings? For that matter, why don't we see more 600 HP S2000s running around all over the place? We know they exist. I think the answer is painfully obvious. They just don't last very long.

and last one how heavy is the stock fly wheel in a AP1
Already asked and answered: http://forums.s2kca.com/showthread.php?t=19349&highlight=flywheel

also i know the 00-01 run really rich but i just had someone else tell emt hat they run lean while in vtec something like 17:1 with a cat on. which is true?

I can't comment on this as I've never had a wide band when my car was NA. You should find out how this "someone" made the determination of 17.1. If it was done on a dyno with the cat on, then the a/f would have likely been taken with a tailpipe sensor. This may not be the best place to measure a/f since the cat has cleaned up much of the exhaust by the time it gets to the tip. Only if the a/f was measured using a dedicated O2 sensor mounted in the exhaust manifold just before the cat, can a true a/f be obtained. Additionally, those who use a narrow band "Christmas tree" light type of a/f gauge is reading a/f via the stock O2 sensor. This would be purely an extrapolation of the lighted region to come up with a number. Not only is this just a "guesstimate", but the stock O2 sensor is not designed to be interpretted in this fashion.

[hayabusa1285]

I'm not sure I'm getting the true idea of this statement, so I'm guessing here. There already exists "solid" diff mounts:
http://www.aj-racing.com/catalog/product.php?productid=1273
Unless you are in a racing application or are in the business of racing and have the budget to replace and rebuild stuff, this would be very ill-advised. Things on this car are designed the way they are to maximize track performance while giving it a modicum of streetability, drivability and longevity. Changing the car in even one area, strips away some of the attributes of another.
For example, we always get discussions of engine torque dampers from time to time and the general consensus is that these are more for show than anything else. Perhaps on a pure track car, you would find a small benefit from limiting the normal movement of the engine, but for a daily driven street car, this would be detrimental to the longevity of the car as a whole and the small difference they make, tend to be quite minor and hard to perceive by the vast majority of S2000 drivers.
All cars have components that normally move and vibrate. If we didn't allow for some "controlled" movement, these motions and vibrations would get transmitted to things that would simply wear out much sooner than desired. This is why we have fluid filled engine and rear diff mounts and rubber tranny mounts. Why do we not have solid mounts where we have rubber or neoprene suspension bushings? For that matter, why don't we see more 600 HP S2000s running around all over the place? We know they exist. I think the answer is painfully obvious. They just don't last very long.


Already asked and answered: http://forums.s2kca.com/showthread.php?t=19349&highlight=flywheel


I can't comment on this as I've never had a wide band when my car was NA. You should find out how this "someone" made the determination of 17.1. If it was done on a dyno with the cat on, then the a/f would have likely been taken with a tailpipe sensor. This may not be the best place to measure a/f since the cat has cleaned up much of the exhaust by the time it gets to the tip. Only if the a/f was measured using a dedicated O2 sensor mounted in the exhaust manifold just before the cat, can a true a/f be obtained. Additionally, those who use a narrow band "Christmas tree" light type of a/f gauge is reading a/f via the stock O2 sensor. This would be purely an extrapolation of the lighted region to come up with a number. Not only is this just a "guesstimate", but the stock O2 sensor is not designed to be interpretted in this fashion.

sorry ment to say no cat. and if i am not mistaken hey said he got it from s2ki.com from what forum i dunno ill have to ask him. but from what i can remember the computer in 00-01 run rich.

and i feel dumb i even asked that question.

and what u said bout the mounts is i feel i dont wanna shorten the life of my compents and i felt by doing that you would shorten the life of the diff

[repiv]

but from what i can remember the computer in 00-01 run rich.

and what u said bout the mounts is i feel i dont wanna shorten the life of my compents and i felt by doing that you would shorten the life of the diff

I believe they do run a bit rich, that's why I'm somewhat surprised to see that it ran so lean in VTEC. More investigation would be in order. Honda engines can be quite tolerant of lean burn throughout the rpm band. The Ale, being developed in Maple Ridge, Canada, is claimed to run as lean as 20:1 and get almost 100 mpg on an otherwise unaltered Honda motor. I have seen as high as 16:1 on my own car when just coasting steady state, NOT under boost.

Just as I think that using solid diff mounts (in the extreme case) would not produce noticable performance gains, I don't believe they would cause severe or sudden degradation of the rear diff. However, having said this, if you combine a bunch of things (like solid engine, diff and tranny mounts), the sum of the parts may contribute more than the each single part (in a detrimental way). If such mods were to be chosen, then much more attention must be paid toward fluid maintenance and inspection.

[hayabusa1285]

I believe they do run a bit rich, that's why I'm somewhat surprised to see that it ran so lean in VTEC. More investigation would be in order. Honda engines can be quite tolerant of lean burn throughout the rpm band. The Ale, being developed in Maple Ridge, Canada, is claimed to run as lean as 20:1 and get almost 100 mpg on an otherwise unaltered Honda motor. I have seen as high as 16:1 on my own car when just coasting steady state, NOT under boost.

Just as I think that using solid diff mounts (in the extreme case) would not produce noticable performance gains, I don't believe they would cause severe or sudden degradation of the rear diff. However, having said this, if you combine a bunch of things (like solid engine, diff and tranny mounts), the sum of the parts may contribute more than the each single part (in a detrimental way). If such mods were to be chosen, then much more attention must be paid toward fluid maintenance and inspection.


Ya i'll have to ask him where he found this out from. to me it doesnt seem right. wow 20:. having just started to learn A/F mixtures but from the lil a know thats just :eek: but 100mpg seems very nice

ya i dont think the diff would just fail soon after the mounts were change out but in the end the car is still my DD and i put on bout 60 miles a day so i cant really be worrying to much bout my diff giving out on me. maybe someday when my car spends the remaining years of it life on a track something to this nature would be something i look at. thanks for your imput repiv and jonboy

[bimdub]

filling the diff mounts with silicone used to be a trick for things like my old BMW 320......now you can get polyurethane mounts for it......I would stay away from steel or anything hard like that....but I can see that polyurethane would be ok......the key is that the diff actually does not need to move much at all......the suspension is supposed to take up the movement, but the OEM mounts are there for "shock reduction" so if you stiffen up the mounts you have to be careful not to "shock" the diff to much......as for making it go better down the road? probably not even worth the trouble.......I doubt that there are but a very select few in this world that would even notice any difference as most of us just can not drive the car to its fullest.....

my :twocents: