Thread: JGY transmission questions

i have seen a couple threads on this from the past but i just wanted to start a new and get current up to date answer...

i have a fully built direct port nitrous b13 that is making probably jut over 400 whp for now... looking to do a bigger shot and dyno tune this spring and should be at atleast 500 whp once that is done...

i need to do some trans work... i have been running a stock b13 and pretty much launching gentle with it... well, the one time i decided to actually launch hard, i cracked the trans beyond repair... and of course i had no way to tell and made the pass and don't feel comfortable trying to salvage it after running it dry...

so has anyone had any luck with the cryo treating and shot peening along with the case welding they offer? i want something that is going to be pretty damn strong and reliable for some launches and not cost me thousands... i would get a b15, but i don't want to spend a grand on a stock transmission...

any insight would be greatly appreciated along with any other ideas on who can build these trans'...

i also see a nismo lsd listed on the site for $850... anyone have any experience with them or any knowledge? that or also about the "JGY Customs Friction type LSD" they offer for $219... seems really cheap... thanks in advance!

-Sam

also if you feel this is in the wrong section please move it where appropriate

I would say for the time, effort, and money you are going to spend through jgay on a band aid solution for an aging trans, you would be better off investing in a P11 tranny (longer gears than B15), or going the 6 speed spec v route.

If you have plans on putting down serious power like that, you may as well do it right the first time and be done with it. Put some Redline shockproof in the new tranny and take decent care of it and I think you will be fine.

I have a built B14 tranny in my 10:1 car that has everything you mentioned done, and I still felt more comfortable with the P11 I put in my old turbo car. Just speaking from personal experience.

that's true... i'm just on such a tight budget this year with the car... i was thinking p11 but i would have a couple thousand in it to get it built... and i don't know if i trust any stock one launching hard... it's looking like jgy would be around $600 for the cryo and shot peened and welding... and i have a spare b13 trans... i know that the smart thing would be to invest in a stronger trans altogether, but the funds may stop that for the time being...

I'm *guessing* that a stock B15/P11 would be stronger than a built B13 tranny.


You can buy a B15/P11 for between....$700 and a $1,000.00. Depending on your sources, freinds, connections. I paid $800.00 for my B15 tranny from G-spec a couple years back.

Here's Andreas with a VERY nice tranny at $1,100.00, a bit much for your budget, but pre-modified for cable, and cleaned up to the tits.

http://www.sr20-forum.com/naturally-aspirated/41001-fl-2002-p11-trans-sale.html


Drop it in, baby it, save your funds and buy a B15/P11.

1) Prothane motor/tranny mounts or equivalent (JWT, Nismo, Place Racing...)

2) Redline Shockproof.

3) Andreas Miko Tranny Saver Bracket: http://www.sr20-forum.com/naturally-aspirated/11706-tranny-brackets-sale.html (which will also work on a B15/P11)

OR....sell your B13 tranny ($200-300) and add it to your $500.00. Now you can go shopping for a deal on a B15/P11.

I am highly biased AGAINST the B13 tranny. A worthless, poorly engineered, inherently fragile peice-of-shit that should have been a complete factory recall. And the B14 "band-aid" was not much better, nor did it solve the major issues with the B13 tranny. BenFenner will disagree with this last statement.

First I will answer the diff question. The nismo unit is no longer in production and they sell another brand that is close. the jgy diff is just like a phantom grip unit. they do work well. As for the transmission it self I would go with a b15/p11 unit or switch to the spec v tranny. I am waiting to see how much abuse the spec v tranny will take since i know the RTR spec v race car could not keep a tranny in one piece.

The spec trans will hold 500whp relatively reliably given it has heavy shockproof and a sprung clutch. The gears are substantially beefier, and the shafts are 5mm larger in diameter which should reduce gear spread. The shaft length is also kept very short, and there are 3 shafts instead of 2. The reverse is completely separate.

The B15 is pretty short gearing. The P11 was still rather short for my taste, until I started revving to 8500+rpm. Then it started getting fun!

Gear oil and clutch selection have a ton to do with what the trans will handle. However, the P11 gearbox still does not hold up to 400+whp very reliably. Not in my experiences, even with a sprung clutch and heavy shockproof. I guess if you used a weaker clutch it could, but weak clutches don't hold up to sub 2.0 60' launches very well.

But the RS6 trans is a pretty expensive endeavor. There are still a few kinks getting worked out with some of the parts, and their availability. Expect to spend close to $3000 for a complete swap. But the benefits are a stronger transmission with a better differential, and can be purchased from a junk yard for only $400-$500 bucks. So if you break them, it doesn't break you.

my .02

p11 only way to go .

JGY sucks for 1 and you should never buy anything from them! 2 I say save for a p11. It'll be worth it in the end. If my trans goes this year that's what I'm gonna do. I'm on my 3rd b13/b14 trans with 300hp...

Care to elaborate a little bit more on this?

they no longer make the nismo diff. Carbonetic is the brand they sell now. Its a clutch type diff. Thmotorsports also sells this brand.