S2000 Under The Hood S2000 Technical and Mechanical discussions.

another diff bites the dust (long)

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Old Jun 12, 2001 | 08:34 PM
  #31  
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Originally posted by Sev


Most cars will break their differentials and drivetrain components if subjected to high RPM clutch drops repeatedly.

The reason they don't is that it is actually faster to do a "clutch slip" take-off at mid to low RPMs then to do a clutch drop at high RPMs.

This is why cars like the lude and the R aren't breaking anything. Have you ever had the need to do a take-off with a clutch drop at 6k rpm in your lude??????????????

The reason we do it in the s2k is because our clutch won't grab unless the wheels are shocked into spinning at higher RPM.

Thus, change the clutch for a strong one, and you will eliminate the need for aggressive clutch dropping.
I don't know much about RWD take-offs, but I do know that Camaros take off the same. Rev high and clutch dump. They are pushing loads of power back there. I have no idea how many diffs they fry. I agree with you that if the clutch was slipped then there would be less of a chance of the diff frying. My point is only that a clutch dump may still give you better 1/4 times and if so, regardless of clutch strength, the diff would still be stressed. It kinda has me worried that a car I'm gonna get and possibly Supercharge has a weak diff. I will do clutch dumps from time to time. But still IMHO, the S2000 shoudl not have diff problems. They should have a strong clutch as well.

On a seperate note, the FAQ says if you have a flat in the rear, move a front tire to the rear and use the spare on the front. Did anyone who fried their diff have flats?
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Old Jun 12, 2001 | 09:35 PM
  #32  
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I think the diff failures might be related to the torsen... In my experience, the torsen starts to give a lot of resistance as it wears out. That resistance might contribute to excessive strain on the casing. That's just my guess tho.

BTW, I have had two rear ends go bad on me. I've had one blowout a few days after I first got the car. I used the front tire on the rear like the manual says and drove very slowly until I got home.
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Old Jun 13, 2001 | 06:36 AM
  #33  
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[QUOTE]Originally posted by gabedude
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I don't know much about RWD take-offs, but I do know that Camaros take off the same.
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Old Jun 13, 2001 | 09:17 AM
  #34  
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Originally posted by Sev


The f-bodies Rev about 2k-3k on grippy asphalt in order to launch, anything more and they will spin and loose time.

The problem isn't only the torque, it's also the following.

At 2-3k RPM, an F-body is forced to go from stop to 14 to 24 mph.

At6-7k RPM and s2k is forced to go from stop to 29-37 mph.



It's puts more stress on the parts when you have to accellerate to a higher speed.... I don't know if i am explaining this well...

Also, on all VTEC cars i have driven including the lude, slipping the clutch propelry yields better 1/4 mile times then dropping it.
Gotcha. The only other Vtec car that is RWD is the NSX. Does anyone know how they launch? With a strong clutch we would probably launch similarly. I am pretty sure Wesmaster still dumps his clutch at around 6000-7000 with an ACT clutch and a supercharger. ACT is what? 40% stronger or so? I know in order to launch good in a FWD car, you have to feather the clutch. But with RWD and an LSD, feathering may not be as good as dumping cause all the weight transfers to the rear on takeoff. I'm just speculating and going from what I know. All the car mags do clutch dumps in their tests. You'd think if feathering gave better times they might try that. That's why all the FWD cars are rated slower than they really are. Dumping in a FWD car just creates huge wheelspin. I see where dumping at 7000 rpms can create stress, but its still only what 150 lb/ft? That just doesn't seem right for it to break.

Someone also posted that we use Miata Rear Ends? If so, we can definitely see where Honda cut corners. A Miata has 140 hp, the S2000 has 100hp more!

I just don't see a clutch helping that much. Sure it may save it for awhile, but there are also diffs breaking that were not abused. They need to fix the diff even if they change the clutch as well.
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Old Jun 13, 2001 | 10:33 AM
  #35  
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service manager called me today. honda NA will do a one time goodwill warrantee repair, very reluctantly. part is about $3k. i will have the opportunity to take pictures once the new part is here and the old one is taken out.
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Old Jun 13, 2001 | 10:44 AM
  #36  
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Good deal josh. Once they take off that old differential, let us know what caused it to go bad.
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Old Jun 13, 2001 | 12:33 PM
  #37  
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[QUOTE]Originally posted by gabedude
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Gotcha.
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Old Jun 13, 2001 | 02:57 PM
  #38  
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Originally posted by Sev


The reason the mags don't do it is because it would take too much time and practice with the particular car.

Just dumping it is easier and more consistent for all cars.

Slipping the clutch in a practiced way yields "controlled wheelspin".

controlled wheelspin = good times.
So just to get it right, you need to be right at that edge where wheelspin is happenning, but you are still getting traction. That can be done one of two ways:

1. Dropping the clutch and modulating the gas pedal.

2. Easing the clutch out while having the gas all the way down (or at one point) while inducing wheelspin. At the same time feathering the clutch to get wheelspin and grip with the gas on. (This is what I do in my Prelude)

So do alot of Camaro owners just dump it cause its easier? Still, there would be some clutch dumping cause it is easier than slipping the clutch. It took me awhile to get my Prelude right where I can launch well. Still I get beat alot by RWD cars who just dump. But mine is FWD.

I just think that regardless, people will still be breaking differentials even if they had a strong clutch. I've heard alot about pre-loading the drivetrain before dumping. That seems easy. Do you all do this that have had broken diffs?
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Old Jun 13, 2001 | 03:17 PM
  #39  
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[QUOTE]Originally posted by josh3io
[B]service manager called me today.
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Old Jun 13, 2001 | 07:03 PM
  #40  
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[QUOTE]Originally posted by gabedude
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2.
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