Does anyone know FOR SURE what rpm I should be at going 60mph with a jdm itr 98 spec tranny??

 

Yes.

https://honda-tech.com/forums/forumd...ysprune=&f=127

 

Bump

 

Did you try posting in the *proper* forum or using any of the multiple online transmission calculators?

Don't be so obtuse.

 

if your refering to which gear it might help. its about 3500rpm 5th gear

 

easiest way is to check the black stamp, second easiest way is to look at the online gear charts and do the math. that particular trans is mostly sold by importers who deal with identifiable gear most of the time. if this is a "some guy" deal have him provide the receipt showing what it is.

ITR transmissions of any sort with no paperwork i would avoid, chance of stolen property is just too high. even if the vin tag is gone it's bad karma for the car

 

Well most people don't cruise 60 in anything but 5th smart ***

 

I'm going to buy one buy it's has been painted and there is no stamp now and the only way I could tell if it was real is to match the rpm and I can't find it anywhere. I have found what people think it might be but not a real answer

 

check for the LSD to make sure you at least have an itr box. value wise the two styles aren't much different and the b16 gearset is actually better matched. using the lower FD with the b16 1-3 gears and gsr 4-5 gears is good for autocross but the 3-4 shift will kill any advantage in the 1/4 or most road courses

 

^Not only ITR transes have LSDs. As a matter of fact, the ITR isn't the only one with a S80 case and a LSD.

The gearing for B16s and for USDM ITRs and JDM 96-97 ITRs is the same. The JDM 4.78FD trans has a GSR 4th and 5th. In 5th gear, the JDM ITR 4.78FD trans should have the engine revved up a bit higher than a USDM or 97spec ITR trans. Maybe like 100RPM of a difference at 60.

Just check for 2nd gear to end around 58MPH at 8400RPM. If you can rev to 8400 and get to 62mph in 2nd, it's a 4.4FD ITR or B16 SI-R trans.

The 98+ ITR trans casing has:
-NE3 LSD stamped on it.
-Has a S80 tag on it
-Has a OBD2 style vent plug (a lot of B16 transes are OBD1 and have the dome style plug).

58mph in 2nd at 8400 rpm is the easiest way to tell once the trans is in the car.

 

The only sure way to check is to open it up.

Tire size will affect your rpm/mph.

Don't put too much stock into a 13 year old cluster.

 

1-2-3 is where you would really notice the difference. the other trans i suppose it could be is a CTR trans but even if, meh, still a good box.

buying these transmissions used is a bitch though, never know what you're getting of if it will grind. i actually wound up buying a new in the box USDM ITR trans myself for this reason

 

The CTR trans is the same as the ITR trans, IIRC. S80 LSD.

 

thought they had the viscous lsd? or clutch lsd? didn't think the itr /ctr used the same lsd

 

All Honda FWD LSDs are helical. I believe that the only ones that aren't helical are found in 4WD vehicles. Clutching type LSDs for FWD is generally a bad idea unless it's for a track car. Viscous LSDs are good when found in garbage cans.

 

now that i know isn't true. the jdm gsr uses a viscous. even M factory will confirm this

https://honda-tech.com/forums/acura-integra-6/what-differential-2941932/

 

No....it's a helical S80 LSD in the SIR-G

 

so you're saying not only am i wrong, you're saying , m factory, the place that builds god knows how many transmissions is wrong?

mm..kay

 

Any confirmations on this lsd debate?

Any reason why the helical is so much better then the viscous? From what I read they both have their (+)'s and (-)'s

 

Helical LSDs actually lock down. The viscous LSD relies on silicone fluid to heat up and then the plates eventually (sort of) lock up. It sucks....unless it's used on a 4WD vehicle.

The advantage of a helical is that it never wears out. There's no clutchpacks, no special fluid, no nothing. Just a worm gear that locks.

The disadvantage of helicals is that they only work if BOTH wheels are on the ground or if there isn't a huge delta in traction between the wheels (one wheel is on very smooth ice and the other is only dry asphalt). It works on torque multplication. If you multiply anything by 0, you always get 0. There's a gear ratio that will multiply torque to send to the non slipping wheel by X ratio.

From what I've seen, helicals don't work on decel and acceleration. Clutch pack or Viscous LSDs can be set up to be 1 way (only locked on acceleration), 2 way (locked both ways) or 1.5 way (half locking power on decel).

I like helical diffs because there's nothing to wear out and the locking action is very solid. There's no slipping clutches to worry about. Special fluid for clutching diffs sometimes costs a fortune and they tend to chatter around turns and stuff. Helical LSDs are very smooth and solid feeling.

I hate viscous LSDs. I had one on my S13.

 

I have to agree with b serious that the gsr LSD would be a helical/gear type if oem (from the motors that I have seen and had myself including JDM gsr motor).

If there ever was a viscous LSD, what oem fluid did Honda use in it? I'm curious about that.


I'm using a clutch type LSD now and love it but the cost of the trans fluid is pretty expensive and also the fact that the plates will wear out eventually. I spent an hour doing circles to break in my LSD and it makes no noise or chatter unless it's really cold and I make a tight turn.

Also, I'm using a ctr trans with a 4.7fd right now. I believe the 4-5 are slightly shorter than the JDM 98 spec trans i had.

 

One way to find out for sure would be to find someone with a jdm SiR-G trans with an LSD and have them open it...

 

Viscous LSDs don't need special fluid usually. The silicone packs are sealed.

What code is on your CTR trans and does the black stamp say NE3 LSD?

 

i posted a link, direct with a thread m factory commented on about the oem viscous units. anyone bother reading it?

not sure where the "lsd debate" is? the early sir-g optional lsd was viscous. if they changed to helical in the later years, no idea. if one of the best companies in the honda transmission world isn't enough proof for some of you, i don't know what else to say.

 

I read it, also read a few more places that confirmed that the optional LSD for the y80 trans was viscous. Im more trying to get b serious to open his trans so I know what it is for sure.