I came across this site earlier today while trying to figure out if my car is equipped with a JDM or USDM S1 trans
http://www.fatboyraceworks.com...are=1

At first I thought I had a JDM S1 trans, but on the highway at about 80-82mph it is very close to 5000 rpm in fifth gear. With the stock 185/60-14 tires, you'll see that the JDM S1 with the 4.40 FD should read about 91mph at 5000 rpm, totally not my case.

The trans is stamped S1-1036662.

As I worked around with different S1 configurations, a JDM S1 trans with a 4.7 final drive OR a USDM S1 trans with a 4.928 final drive both seem like they could be what I have as they are both extremely close to the mph's/rpm's mine turns.
EDIT: It looks like JDM S1 trans w/ 4.928 FD may actually be spot on

Is there a way to tell visually or from the serial number on my trans which trans (usdm or jdm) that I have?

Right now I'd venture to guess the JDM trans + 4.928 FD as its closer.

Thanks

JDM S1 trans + 4.7 FD vs. USDM S1 trans + 4.928 FD calculations





Modified by vacantskies88 at 7:34 PM 12/27/2007

 

as far as i know there is no company that makes a aftermarket final drive for s1,j1's except mfactory and they just came out with them not to long ago. theres no way to make the jdm 4.7 final fit

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4g hatch &raquo;</TD></TR><TR><TD CLASS="quote">.....except mfactory and they just came out with them not to long ago. theres no way to make the jdm 4.7 final fit</TD></TR></TABLE>

Yea, and thats what makes me wonder what's really going on. The trans is stamped S1-1036662. The owner before me only drove the car about 10 miles after purchasing it (late 2006) from the previous owner so that pretty much puts the MFactory gear out of the equation because all of the work was done by the owner before him. I just went out and took some rough measurements, they may have been +/- 1.

4th Gear
<U>RPM___MPH</U>
5000-------68
6000-------81
7000-------94

5th Gear
<U>RPM___MPH</U>
3000-------49
4000-------65
5000-------81
6000-------98
7000-------114

My 5th gear on-road measurements are nearly dead on with the calculated JDM S1 + 4.298, but 4th gear is off by 6mph at 5000rpm, 7mph at 6000rpm, and 7mph at 7000rpm.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 4g hatch &raquo;</TD></TR><TR><TD CLASS="quote">as far as i know there is no company that makes a aftermarket final drive for s1,j1's except mfactory and they just came out with them not to long ago. theres no way to make the jdm 4.7 final fit</TD></TR></TABLE>

Beyond aftermarket parts are there any other known gears that fit the cable tranny? Similar to the way Kia gear's can be used in S2000s?

 

still looking for opinions

 

the u.s s1's,a1's jdm y1's,s1's,and j1's gears can all interchange,as far as i know but if you change the final drive then you use the matching countershaft

 

If you want to know, pull the trans and count the teeth. People on here will be able to give you guesses. No telling if the former owner of the trans swapped gears in it or not.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Aquafina &raquo;</TD></TR><TR><TD CLASS="quote">If you want to know, pull the trans and count the teeth. People on here will be able to give you guesses. No telling if the former owner of the trans swapped gears in it or not.</TD></TR></TABLE>

i agree thats the only way to know for sure. like the u.s s1 and the jdm counterpart have the same 4.40 final but youll have to check the gear ratio's cause the u.s has longer gearing

 

my question is does it realy matter? are you happy with your gearing? i would think if it rips why stress about what gearing you have. just enjoy your short gears.

 

Count the teeth if you absolutely must know.

Driven / Driver = Ratio

 

A good transmission setup can make a subpar engine perform half decent. Gearing is the most overlooked part of a good N/A setup IMO.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Aquafina &raquo;</TD></TR><TR><TD CLASS="quote">A good transmission setup can make a subpar engine perform half decent. Gearing is the most overlooked part of a good N/A setup IMO.</TD></TR></TABLE>

It does rip pretty well. Coming from a VR6 with a 3.39 FD to this is alot of fun, you don't even notice the missing torque. It actually feels peppier than my s2000.