Recently I purchaed a '90 CRX Si with a JDM B16A installed in it, the head is marked 89, so it's a fairly old head, and I can only assume that the that the block and tranny are from the same timeframe...however after looking at another thread where people were complaining about 5,000rpm and 80mph(normal for my itr with JDM 4.785FD), it leads me to believe that I have a different tranny installed in the car than I thought.

At 80mph in 5th gear the speedo reads ~3,900 rpm, I finally cleaned the block and tranny off enough to note that the tranny has a label(right next to the block ID) that says S1, with it's particular ID number. So now I know that I have an S1 tranny...leads me to believe that it's a USDM tranny, however the person that I purchased the car from doesn't know anything about it(he bought the engine from someone and had a shop install it, he was ~17 when they did it, and he didn't know a whole lot). Looking at the invoice for the swap it doesn't designate that it's a US, or JDM tranny...could be that the tranny was bad and they replaced it with a USDM tranny.

Question: Other than the gearing calculator, and tearing down the tranny to count teeth, is there a way to find out which S1 tranny that I have?

Thank you,
Austin

 

honda trannies are a pain in the buttock to identify from their number. Counting teeth is a surefire way, but the gearing calculator would work just as good. Other than that you're SOL (to the best of my knowledge at least)
I'll watch this thread though, hopefully I'll be proven wrong

 

That 3.9k rpm seems really low at 80mph. Your tach may be off by 500-700rpm or you have a USDM tranny.

 

If you're not extremely irritated by high RPM at 80mph then you have the USDM.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SoulSurfer &raquo;</TD></TR><TR><TD CLASS="quote">If you're not extremely irritated by high RPM at 80mph then you have the USDM.</TD></TR></TABLE>

I have an itr with a JDM final drive...so this is a luxury for me, I'm going to have to assume that I have the USDM tranny.

 

3.9K at 80mph is pretty good. The JDM S1 is around 4K at 70mph.

 

Do you have a complete 00 spec ITR tranny, or a hybrid 96+ spec with 4.785? If you have a 00 it should be fairly similiar, if you don't, then ya even an S1 will feel long. Tach could easily be off that much.

 

At 80:
The JDM S1/J1 should be 4800-5000rpm
The JDM Y1 should be at 4200-4400

If you're at 3900, I'd say you have a US S1.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Patch &raquo;</TD></TR><TR><TD CLASS="quote">At 80:
The JDM S1/J1 should be 4800-5000rpm
The JDM Y1 should be at 4200-4400

If you're at 3900, I'd say you have a US S1.</TD></TR></TABLE>

At least I know that I can fix the scratch in 3rd, and 4th gear, bad side is that the gearing isn't the best