Synchro replacement or tranny rebuild?

[Electro]

Went and had an oil change today... ended up having to replace my oil pan gasket - with the oil change, filter and oil pan gasket plus labor it was $209.62. Didnt exactly expect to pay *that* much...

anyways, I was talking to one of the guys about where they would recommend me taking my 91 NSX to get the 90k done and synchro replacement.. and he suggested that i should go ahead and put the short gears in it rather than rebuilding the transmission...

now replacing the synchros isnt exactly rebuilding the transmission is it?

The whole setup - 90k service, new dali comp. clutch and flywheel and replacement of the synchros is going to run me at about $4500 - and i really dont want to spend any more than that as it is.

I'm confused now though... whats the difference between the R&P and the short gears? i see them as 2 seperate items on comptechusa.com ... thanks for the help

 

[maomaonsx]

send me an e-mail
I'm thinking about selling my tranny and upgrade to 6-speed.
I have short gears and 4.23

------------------
Please visit my NSX tuning page! Mods, Japanese NSX related stuff, pics!
http://www.geocities.com/Tokyo/Dojo/6073/index.html

 

[nsxtasy]

whats the difference between the R&P and the short gears?

The power is transmitted through one of the various gears (first through fifth or sixth) AND through the ring and pinion gear. Thus changing the ratio of the R&P gear changes the overall gearing no matter which gear you are actually in (first through fifth or sixth). The short gears replace the stock second through fourth gears of the five-speed, so they only change the gearing in those particular gears.

More info in the FAQ at http://www.nsxprime.com/FAQ/Performance/gears.htm

 

[Electro]

Ok i've read the FAQ ...

What is the difference in performance on a stock 91 5spd NSX with just the R&P vs. a stock 91 5spd NSX with the short gears? That really wasnt touched on in the FAQ. Thanks

 

[nsxtasy]

What is the difference in performance on a stock 91 5spd NSX with just the R&P vs. a stock 91 5spd NSX with the short gears? That really wasnt touched on in the FAQ.

Yes it is. Perhaps you didn't scroll down to the table under the heading "What are the Numbers". Keep in mind that the "Japanese 5-speed" is the same as the short gears. There are columns for each of the two non-stock R&P gear ratios available.

[This message has been edited by nsxtasy (edited 18 January 2001).]

 

[Lud]

Originally posted by Electro:
now replacing the synchros isnt exactly rebuilding the transmission is it?

No, but due to the labor costs involved in any transmission work, it makes sense to overhaul it anytime you open it up, meaning check tolerances and replace any parts showing wear. The individual parts inside the transmission that tend to wear out are not all that expensive, but the labor is around $800 +/- depending on your shop's rates.

So by the same token, if you were considering doing a short gear set or R&P mod at some point, this is the time to do it since you have to open the tranny anyway for the synchro work. You're basically getting an $800 labor discount on the mod because you have to pay that labor anyway for the repair job.

I'm confused now though... whats the difference between the R&P and the short gears? i see them as 2 seperate items on comptechusa.com ... thanks for the help

They are two different items. Short gears are the selectable (via the shifter) drive gears in the transmission. The short gear set replaces gears 2, 3 and 4 and the related parts. When you replace those parts, the only thing affectes is the gear ratio for those gears.

The R&P is the final gear set that is driven by the main gears (1-5). A change to the R&P affects all gears because all gears connect to the R&P which is eventually connected to the wheels.