[QUOTE]Originally posted by Luis
[B]


Sev, one thing to remember, if you shorten the final ratio, you do get more torque at the wheels on every gear. But you do loose a lot

 

Gee lots of things happened since I've been gone for a bit.

There seems to be bit misunderstanding and misinformation going around.
I am the one who has done both ATS final gear and Jets final gear as a caveat.

Let me first clarify one thing.

ATS final gear is entirely different from Ring and pinion swap in differential offering from Spoon and Jets integral Kobe and now J's Racing's

I have seen somewhere that the approximate ATS final gear change is from 4:1 to 4:44 or 4:5
ATS parts involve changing secondary gear or mission in the transmission.
The retail website say removing transmission is not necessary?? Is this suppose to be a joke?
You need to remove transmission.
As matter of fact this is most difficult install among all final gear offerings.
You need to buy new sets of O rings about 13(I am not too sure exact counts)
As well as a pair of bearings(not needed but should do) and the most importantly a shim that needed to be carefully picked from 22 different sizes to prevent getting the bearing chewed out like I have experienced(two bearing failure at 9,000 interval)
Strangely the way the gears are grounded, ATS does not promise to perform silently. Sadly this was admitted by the president of ATS. In my car you will hear whirr or gear noise as the rev increases and coming to a stop. This noise was incredibly loud at the beginning but started to quite down with the mileage. Because of this I am afraid to recommend this to anyone.
But if you are willing to tolerate difficult install and gear whirr noises, you can do this and have the differential section open for interesting mod like mine.

On to the ring and pinion final gear mod:
This does not require transmission removal as stated in the web site again.
You do need to remove differential however where the ring/pinion is housed as well as rear axle. I had posted some during install picture of Jet's ring/pinion gear install and if you have seen it, it is not overly difficult and can be done in 3-5hrs.(the pics are lost I think because I did not keep with photopoint, but if anyone needs to see them e-mail me)
In addition you need to get two bearings and one crush collar because they must be replaced and cannot be reused.
I had know idea J's racing just came out with different spec Ring/Pinion offerings. If I had know n I would've waited for it but I think I am happy with what I have now.
I would certainly recommend the ring/pinion in differential oppse to modding secondary gear like ATS's. If you want some serious oomph starting first gear go with 4.77 or 4.44 even.

Now the serious draw back with this mod. The speedo and consequently the odomter error...
I wasn't scientifically measuring but with ATS the speedo seems to be off by 6-7 mph+
With this mod you will see higher speedo than normal, ex speedo will say 65 but in real you are traveling 58-59mph.
With inclusion of Jet's ring/pinion. My speedo is now off by 9-10mph.
And now dreaded admission, this effects odometer adversely. You will rack up mileage faster than normal so this is serious no-no to many. My current mileage claim of 463000 is not exactly kosher. I am in no mood to seek out correcting the speedo error but I am secretly hoping someone will come out with that or maybe from the companies offering the final gears.

To conclusion:
Should you do this? Absolutely.
This is the best modification that I have done to my car period.
Put it in first and stomp on the gas and you can easily feel the car lurching forward unlike never before. Even in hot 90+ with airconditioner on, the car doesn't seem to slug like it use to.
If you are fortunate to live near DC/MD/VA you are welcome to test drive my car.
With ATS gear I was able to shave off .8 second at the 1/4 mile run drag strip.
Now with both ATS and Jets' ring/pinion I am curious how much better I can do.
With combination of Mugen ECU and final gears( now i am recommending JS racings either 4.44 or 4.77, say good bye to engine bog and high rpm lauching(your differential will thank you)
Still I believe that the major thing that will stop many of you for doing this will be speedo and ultimately the odometer error. You are losing top speed but in return your car will be significantly more movable arourd town.

 

[QUOTE]Originally posted by 1Randyc
[B]
With combination of Mugen ECU and final gears( now i am recommending JS racings either 4.44 or 4.77, say good bye to engine bog and high rpm lauching(your differential will thank you)
Still I believe that the major thing that will stop many of you for doing this will be speedo and ultimately the odometer error.

 

Randy, Is there any way to fix the odometer error? Also where can I get this ATS stuff from? Thanks

 

You know this is an area where motorcycle riders get a lot of benefits and experience.

It is so easy (and cheap) to have a couple of sets of front and rear sprockets available to change gearing on the fly.

A front sprocket change alone (up 1 or down 1 tooth) allows approx 14% (7% up or down either way) variation in gear ratios at a total cost of around $40 ($20 for each sprocket) and a total time for changeover of less than 10 minutes.

It makes it very easy to set your bike up for different tracks. Go out and do a couple of laps - come back in - change sprockets and see if you got it right.

Changing rear sprockets is slightly more costly and time consuming (about twice the price and twice the time) but in combination with front sprocket changes allows almost infinite ratio variations.

Ahh, don't you wish Honda stuck with the old S500/600/800 chain drive? This would have solved our problems so much easier - and yes chains can take 240hp without snapping.

 

top

 

Starting a thread in "Under the Hood" to seek a solution to the speedometer/odometer related issues.

http://www.s2000online.com/forums/showthre...?threadid=20424

 

[QUOTE]Originally posted by DavidM
[B] What you want to table is torque, at the wheels if possible.

 

anyone know where I can get this stuff?

 

I changed the temperature to a little higher so times are a little slower then above....

4.1 Gear (stock)

0-60 5.0
0-100 12.4
0-140 34.03
1/4 mile 13.70
Top speed 150 MPH

4.3 GEAR

0-60 4.9
0-100 12.2
0-140 35.13
1/4 mile 13.69
Top speed 148 MPH

4.44 GEAR

0-60 4.8
0-100 12.1
0-140 33.38
1/4 mile 13.57
Top speed 149 MPH

4.77 GEAR

0-60 5.0
0-100 11.9
0-140 32.71
1/4 mile 13.54
Top speed 144 MPH


The 4.44 is a great performance enhancement. The added drive force at the wheels is superb. The 4.77 would be hard to live with day to day, worth it for autoX though.