Thread: P11 Transmission Article

Steve, any info or experiance with an sr20development trans? I picked one up a few years ago that the oringnal owner says he had it cryo treated and the girdle was welded. I've yet to install it because my stock trans still works and don't feel like swapping the nismo lsd unless I have to.

Yep, blew up a couple and started building my own. I'd just keep it around until your existing one explodes, then see how it does. Don't expect it to last and you'll be fine with it.

Very interesting read Steve. Nice to see you around. I am going with a P11 tranny soon.

i never knew they made gear oil, thats pretty cool! i've been running their synthetic blend motor oil for years and its great stuff.

The added weight of the platform is exactly why the RS6 is such a great transmission. The P10 would have to be checked for clearance for the diff. The B15 and P11 fit the 6 speed without issues, perhaps the p10 would fit it nicely?

I ran the P11 trans for several years. Drag racing and general beating. I blew up 6 transmissions when everyone else still claimed they were practically indestructible. First gear to go was 2nd! of all gears! And I was running heavy shockproof. Each transmission after that seemed to live a shorter and shorter life. You can even see me on youtube shattering 3rd on about 320whp getting on the freeway. Gear fatigue is a bitch.

The transmission swap is not cheap, but everything else for it is. Axles, super strong and easy to source. Clutch, 240sx. They are cheap and everywhere. The p11 transmission is not much stronger than the 32. And I will maintain and go on record by saying; If you plan on tracking this car competitively, there is little chance of this transmission surviving. The RS5F70V/A is not strong enough for 300whp continuously. And I believe it will break. But, replacements are cheap and plentiful!

As far as the Brembos, weight isn't much of an issue. The calipers are lighter than the standard calipers, since they are aluminum. Rotors are WAY cheaper, and there are a ton of pad options. Sure there is more weight, but it really is marginal. Just gotta run larger wheels... so I totally can understand not using the Brembo setup. It's justifiable.

I do agree with Ashton on many points. I also agree with Steve when it comes to shift feel. The shifts feel smooth, but less precise. But you're really nitpicking at that point. Staying with the old tech keeps things simpler. But overall cost in the long run... I think the 6 speed would be the way to go.

I posted on Mike's FB earlier Yesterday about this issue. Though I don't think the RS6 is going to be bullet-proof, I do feel it is going to last much longer. The size of the shafts, gear teeth, and case structure all ensure much longer operation. The P11 transmission has a stronger case, and better structure to reduce shaft flex. But the gears are practically the same as the old P10 transmission.

The external dimensions of the gears isn't much different, but the shaft diameter is larger, and the gears are cut deeper for more contact area.

I agree, however, this transmission would not last if we were racing it competitively with 300whp. Luckily, we're only running 208whp.

Again, I believe the 51H is overkill for our needs and sticks us with a subpar diff in a heavier trans. Anyone who's driven a NISMO LSD-equipped car would agree. There really is no comparison. Floor it in a corner, and the diff will just yank the car around it. It really is too bad NISMO discontinued it.

This pic from my old build thread sums up the gear differences quite well. The teeth are thicker on the tip, are cut deeper, and the substantially larger shafts reduce flex, and are shorter as well. It's a better transmission all the way around. I've never driven the clutch type LSD, but I can attest the the Helical unit in the 51h being pretty decent. Much better than the VLSD in the older transmissions.

But like you said, the extra weight may not be worth it. I feel good about the P11 trans holding up for a little while longer, but I have reservations about it actually lasting. After all, the gears aren't any larger vs the old 32 box. The reduced gear flex and stronger case help prolong the transmission. But if you guys are breaking the 32, the 70 box likely won't last that much longer. And this is especially the case given the amount of abuse the car sees on the track. Ultimately we'll have to wait and see. I don't wish you bad luck with the new box. I hope it holds up better for you than me.

I disagree with this statement relating to this thread. This is an extremely informative thread with lots of great info. This is new way VS old way and it is being discussed, what is wrong with that? Without this discussion and new ways of doing things, we would probably still be putting T25's on our DE's.

Besides most of the OG's that I know that aren't around are not because of this, its because life takes over and people have full time jobs, families and kids to worry about. Or have gotten out of the SE-R game and have moved onto a different brand/chassis.

Its not like Ashston bashed this guy, he just gave him some different points to look at and try and defend the "new school" transmission option that is out there. Rockwood did not get upset, but he defended his way in a friendly debate on a car forum. If this upsets some of the OG's, sorry, but this is a car forum and that is what happens on one.

I don't believe in Google, like I don't believe in the 6 Speed swap . Oddly enough, when I searched Kendall MTL, it redirected me to Good ol' Dino MTL LOL! Ohhhh the irony............

Thanks BTW! Found some at a local place a few miles from my friend's place. I am having him be my bitch and pick some up

One of the biggest reasons we went 70 (aside from being cheaper and easier)is because we could swap in the NISMO diff. It's THAT good. I've driven a car with a Quaife (helical), and it's great until you hit some curbing. When you do that, it goes open and you temporarily lose all forward power and the car's handling goes to shit temporarily. Usually, when I'm hitting curbing, it's right at the apex, which is the last place you want to lose power in a FWD car that's set up "loose". That freewheeling is also extremely bad for the transmission, as it will have to absorb what is effectively a clutch drop at 90mph with a 100lb flywheel.

With a helical diff, there's no customization that goes into the diff, since it's gear-driven. No preload, no engagement speed and force, nothing. It's either on, or it's off. These are the things that separate the NISMO man-diff from the boys.



Err, you yourself said the following in that same thread:



So, which is it? We're running a stock-disc/JWT PP clutch setup, ultra light flywheel, generally don't use 2nd gear (no throttle-on shifts into 3rd), and are making only 230lb-ft at the wheels.