joel n

We currently have a SIR trans, 4.9FD and wavetrak diff. We just bought a 97 spec type R swap for the car. I was told I could switch the FD and the diff over by a Honda tech, but after looking online more I found 2 part numbers for the diff from the SIR trans and the Type R trans. From what I read the Final drive will switch over NP.

So if the diff cant interchange and we can change the FD is there much difference between the wavetrak diff and the stock Type R diff. both are helical, and that's all I know. lol.

The main reason we what the type R box is so we can get the proper gears back. We currently have a LS integra 2nd gear. Its hurting us a lot out of a few turns. So getting the hole swap will change that but we need the 4.9FD. Also giving us a spare trans finally.

So if the diff and the FD cant be switched over can we switch the input shaft and gears from the counter shaft into the SIR trans keeping the wavetrak diff and 4.9FD?

If I missed this info somewear else I am sorry. Searched a bunch and didn't find anything.

BTW all this is for a 95 Del Sol VTEC road racecar. running a B17A1 motor, soon to be a back-up motor.

Honda Bull

What brand is the 4.9 final drive? ATS or MFactory?

Regardless, final drive and differential will indeed swap over into the Type-R transmission. Without knowing the final drive and what differential was used (B16/LS are different sizes to the GSR/ITR) it's hard to say exactly what is needed in the direct swapping in your exact situation. But overall, all of the parts are interchangeable.

Depending on what all was used in the SIR trans, you may have some incompatibilities with the ring gears (4.9 ring gear may have to remain with the Wavetrac LSD and may not fit the ITR LSD, etc.) and might have some 1st gear (gear, needle bearings, collar) differences due to final drive design with the JDM ITR transmission.

You'll find those things out for sure once you open it up, but it all will transfer over in some way, shape, or form. :p

joel n

I will have to get the boxes and get the part numbers to fully figure out what is in it. I know when Paul (current owner) bought the car he was told it had a GSR box and factory LSD. But once they pulled the trans out they found out it had a SIR box or the stock Del Sol VTEC box. (i am told the SIR and VTEC del sol are the same). So by that i would guess he bought all GSR compatable parts.

The main goal is to get a trans together with the 4.9FD, one of the 2 LSDs, and the type R gears. Or atleast the type R 2nd gear in the current box.

joel n

So it is a MFactory Diff from syncrotech, and the final drive is the type R 4.78 from Gear-X. LOL the car owner thought it was a 4.9FD, till this all came up. dosnt matter, its geared great for the track we run. I called the guys at syncrotech up and he helped me sort out the Part numbers we had. Turns out we have the GSR/ITR diff, and GSR/ITR final drive. he said they use to sell Gear-X stuff. I am much happier now with this all sorted out.
Also big thanks to whoever I was talking to last night at syncrotech. Customer service like that is why we will go back to them when we need new goodies

Honda Bull

Cool! Yeah, Dave and co. @ Synchrotech are always a pleasure to deal with, from questions to ordering - the whole process is fantastic.

I was hestitant to tell you what all would definitely switch over until I knew what final drive you had attained as there are some that compensate for the difference in 1st gear bores. With the information you've provided, I would personally just swap over the MFactory LSD into the ITR transmission and leave the final drive alone that way you don't need to swap any 1st gears / needle bearings, etc. Keep the Gear-X as a back-up incase the OEM fails or sell it to a fellow racer that needs it.

0parts@synchrotech

No problem! Glad we could help!

joel n

We have to change the final drive as we need the ratio. 4.7 to 4.4. We ordered a 97 spec ITR swap from HMO, so we get the 4.4FD. figured since we have the FD and diff already and decent a header, no point in spending another $900 for a 98+ spec ITR swap

It says the FD we have is for the GSR/ITR trans. So it should drop in no problem. Should we order some parts? lol

Honda Bull

Ah! Totally glanced over and missed the "97" model year trans. That does indeed have the 4.400 so definitely understand your desire to transfer the 4.785.

I'm not entirely certain if the Gear X final drive is designed with the USDM or 98-spec JDM Type-R 1st gear and needle bearing in mind. Someone else may have to check in with that to confirm. If it's designed for the USDM ITR/GSR, it'll swap over no issues. If it's designed for the JDM 98+ ITR, you'll need to bring the 1st gear and needle bearings along for the ride.

joel n

From what I was told the USDM and 97 spec JDM trans is the same and this stuff will work. they changed the 98+ spec trans.