Gearbox options!

[madras]

Hi guys, ok so I need to rebuild my gearbox and I had a snap ring come off so looking at a new transmission case as well.

Question is should I go for the JDM 5 speed set (93 car) or stick to the UK/US ratios. I guess there is also the option of fitting a 6 speed, but the JDM 5 speed actually has slightly shorter ratios up to 3rd anyway.
http://www.daliracing.com/v666-5/info/article_read.cfm?articleID=950

Opinions? Should I just get a rebuild service from the US rather than getting the parts delivered?

Thanks.

[NSXGB]

Kaz might be able to help you with supply and rebuild of your box.

Is your transmission case damaged? If not there is a fix to avoid you buying a new case with regard to the snap ring failure.

Depending on your budget, you can rebuild yours replacing all the damaged parts, buy a second hand box (I believe Sudesh has two for sale) or ideally rebuild your box with the short gears (you did not say whether your car is JDM or UK), higher ratio diff etc.

[NoelWatson]

Hi guys, ok so I need to rebuild my gearbox and I had a snap ring come off so looking at a new transmission case as well.

Question is should I go for the JDM 5 speed set (93 car) or stick to the UK/US ratios. I guess there is also the option of fitting a 6 speed, but the JDM 5 speed actually has slightly shorter ratios up to 3rd anyway.
http://www.daliracing.com/v666-5/info/article_read.cfm?articleID=950

Opinions? Should I just get a rebuild service from the US rather than getting the parts delivered?

Thanks.

Can't you do something like 6 speed with shorter final drive, or is that a PITA?

[jaytip]

Is your transmission case damaged? If not there is a fix to avoid you buying a new case with regard to the snap ring failure.


May not have to buy a whole transmission case but you have to buy a part of one because it's the case that is the problem.

[m666 edd]

If money was no problem I'd have a 6spd with a comptech 4.5 final gear.

[Kaz-kzukNA1]

Depending on the spec of your NSX, you may already have shorter gear ratio any way...

Kaz

[NSXGB]

May not have to buy a whole transmission case but you have to buy a part of one because it's the case that is the problem.

Mutley write up a piece on his snap ring repair.
The casing was machined incorrectly at the factory and after a while the snap ring can fail due to being under more stress than it's supposed to be.
I thought a stronger ring was available which negates the need to change the casing?
Anyway, might be irrelevant if it's caused other damage...

EDIT: Just had a read up on it. The sensible \ stress free option would be to bite the bullet and buy the new casing. I'm sure that a decent machine shop could correct the manufacturing defect and supply a suitable replacement snap ring though....

[madras]

Depending on the spec of your NSX, you may already have shorter gear ratio any way...

Kaz

It's standard UK so the longer gearing as far as I know. Honda said gear oil was ok so prob don't need to replace the bearings just all the syncros and gears while it's apart and the slider sets (syncro rings).

Thanks

[m666 edd]

Following on from what Kaz said.

I believe there are some short ratio UK spec NSXs around the 94-96 years or something? I believe most if not all the 3.0 targas are short ratio. Something along those lines I think, could be completely wrong though!

[NSXGB]

Following on from what Kaz said.

I believe there are some short ratio UK spec NSXs around the 94-96 years or something? I believe most if not all the 3.0 targas are short ratio. Something along those lines I think, could be completely wrong though!

Correct....

[Hagasan]

Following on from what Kaz said.

I believe there are some short ratio UK spec NSXs around the 94-96 years or something? I believe most if not all the 3.0 targas are short ratio. Something along those lines I think, could be completely wrong though!

Yep, well 95-96 anyway? My 96 Targa has the JDM gearsets....Thought it did anyway but Kaz confirmed it by the VIN. I was going to by the 6-speeder from Ireland if it hadn't but no real need in my case...

[A.S. Motorsport]

if i recall correctly the post 95 cars got the short ratio, and previous have a EDM gear ratio which is between the US and JDM, (Which would be terribly uneconomical)

[Kaz-kzukNA1]

For UK 5MT NSX, the shorter gear ratio was introduced from 93 model.

However, each country has different definition for the term ‘Year model’ so you really need to confirm it through VIN.
Also, the year model that you were told from your previous owner is not necessarily correct from the VIN point of view.



It's standard UK so the longer gearing as far as I know. Honda said gear oil was ok so prob don't need to replace the bearings just all the syncros and gears while it's apart and the slider sets (syncro rings).

Thanks
As your GBox will be off the car, I'm quite sure your mechanic will inspect the internal parts.
Just for the reference, unless you visually inspect the gears, other parts and the magnet next to the MTF pump, you can’t tell the condition of internal parts by just looking at the drained MTF.

Someone may have replaced the MTF after the damage was done resulting in clean MTF when you drain it.

Burning the sample MTF and analyzing the spectrum is a different story…

Inspecting the MTF strainer/filter will provide you with some info but again it’s not conclusive as not many people clean it every time when the MTF was replaced.

For example, recently I was working on one NSX for the new owner and I found lots of metal particles inside this strainer.

However, the drained MTF was very clean because it was replaced recently. Also, the owner didn't feel any issues with his GBox.

The GBox was definitely opened up by the previous owner(s) before the MTF was replaced as it was equipped with aftermarket LSD. Possibly the damaged parts were replaced at the same time.

Looking at the state of the strainer cover seal, it was never opened and thus, leaving the metal debris from the previous damage.


Hope you will find the best option for your GBox.

Regards,
Kaz