Opinions Please... I'm looking to get the PI TC and an LSD very soon.

For those with the Supra TT and TC, do you find this combination [at least with the 2800 stall] to be too much, i.e- major traction issues. If you could change the stall speed or did change your stall speed to better match the 3.76 gearing, what stall speed would/did you select? Do you have any regrets about the loss maximum speed [if this is indeed a problem, the threads seem inconclusive.] Do you have any problems with noise and uneven engagement through corners?

For those with the TRD LSD and TC, does this combination make you happy or do you wish you had gone with the Supra 3.76? Same questions about noise and uneven engagement through corners?

The LSD options price out quite a bit different, but get much closer as one includes installation labor. The TRD LSD runs about $760 but labor can be significant. The Supra 3.76 runs over $1500 but the labor is minor. Another option I am seriously considering is the new ATS carbon LSD [1.5 way] for $1250 which has similar labor to the TRD. I am also looking at possibly swapping gears to achieve a 3.76 with the non-supra options.

And... For the TRD and Supra TT LSDs, are these 2 way? 1.5 way? 1 way??!

FYI, if anyone is selling a Supra TT 3.76 LSD for cheap, that would make my decision really easy!!!

 

As we have discussed here before. If you want to go with 3.76 gear ratio, you must change the ring and pinion gear at the same time which is equal to the whole SupraTT 3.76 unit. You're looking at cost for LSD + pinion gear + rear end housing.

TRD LSD is a 2 way unit. The major diff. between Torsen and clutch type is the smoothness of gear locking. Torsen style is gradually locking down both wheel while the clutch just locks down immediately. For a quick acceleration out of a corner, clutch type works better than Torsen but you can definitely feel the shaking from the clutch locked down. I'm happy with my TRD LSD/2800 TC combition.

 

Thanks Jacob. I've decided to go with the ATS Carbon 1.5 way LSD and the PI TC/2800 Stall. Between the ordering, waiting for parts and install it will be at least a month before I'll be able to comment on the combination.

Funny, I expected a lot more comments -- normally CL members are not shy when it comes to opinions. Then again, the boards have been pretty quiet lately.

 

Red - Actually, Ethan asked me to write an article on my RMM LSD & I submitted it in early February ( don't know where it's at right now? ) I got the RMM piece more for the stiffer gears than the LSD as I'm more of a quartermiler than autocrosser. Haven't had any problems with the marriage of the 2 but I also haven't tried to see if there was a difference in top speed with the 3.76 gears. Not other negative comments on the mods other than the loss of about 1 highway mpg due to the 2800 stall speed.

 

just want to add this: the clutch type LSD (TRD) will need rebuilt depend on your usage, the clutch will wear out, planning another chunk of $$$ for installation labor sometime in the future if you are planning to keep the car for a LONG time hee hee. The Supra TT (torsen gear) LSD are supposed to last forever, granted that you are not putting 400+HP into it.

 

Nothing like a comment about the "lack of comments" to get a response. I know that Ethan solicited a number of CL regulars for articles on various mods and I suspect that also has contributed to the slow down in the CL forums. Everyone is either burnt from writing the articles or does not want to duplicate what they so pain stakingly put together for Ethan.

Here's a link to the ATS web site and specifically to the ATS Carbon LSD:

http://www.a-t-s-usa.com/ats-products/lsd-carbon.shtml

The unit is 50% more expensive than the TRD and with labor is probably the equivalent of the Supra TT Torsen LSD. Is it worth it? I certainly hope so! I have had several incidents in the last week where I could have used some form of LSD -- I pulled into traffic with a heavy foot only to have the traction control cut the gas.

 

Well, turn off your TC! You'll have the same problem even with a LSD installed - if you get into it with your TC on it's going to shut you down. Maybe you'll go a bit longer before you do, but I can easily get mine to click on and I don't even have the steeper gearing (my LSD is a TRD variety).

I am happy with the TRD LSD. I got it because I eventually will add some sort of FI to my GS. I'd like the gears from the Supra LSD, but I've never regretted my decision. No problems with noise (I use Redline fluid) or uneven engagement through corners, but I haven't been out drifting.

Sorry I didn't respond; I totally missed this thead when you posted it last week somehow. Thanks for being the guinea pig and trying a new product for the everyone!

 

Hi, there!

I was wondering if someone could point me to some material which explains the diference between 1- vs. 1.5- vs. 2-way differentials.

I know what the LSD is supposed to do (in theory), but the "way" term is new to me.


Any info is appreciated.

 

Nope, no major traciton issues. I can brake it loose when I want to, but the TC keeps things planted.

The added pop out of the hole is nice. And with larger tires + wheels, the hole shot puts things back to near stock ratios.

I wouldn't change the stall speed.

No regrest about max speed. I rarely get above 80 unless I'm passing someone, usually.

No problems with noise and / or uneven engagement through corners. Mine has always been smooth. Now, when turning slowly, likke for a stop, and my wheels are turned all the way to one side (think 3-pt-turn), and I goose it a little, I can feel the LSD working, gripping, but that makes me feel good actually.

I don't have any answers to the 'way' questions.

 

guru pointed me to the basics: http://auto.howstuffworks.com/differential5.htm

And I found several other sites with good information, also, such as: http://www.twelve100.com/faq%20and%2...ential_101.htm. And here is a great white paper on Torsen differentials: http://auto.howstuffworks.com/framed...ferential.html

If you go to any of the manufacturers you will find more information: ATS, KAAZ, Cusco, etc. Also, do a google search on "limited slip differential 1.5 2 way" and you will get a bunch of good hits.

The two way appears to be better for straight line performance such as drag racing, the 1.5 way seems to be better for the twisties. I say "seems" because there is a LOT of opinion involved.

 

Well, without the LSD the traction control is still better than sitting and spinning on an open differential. My cars suspension is as tight as <off color reference here> and corners and uneven surfaces highlight just how traction impaired I am. I am usually better at modulating the accelerator but occasionally I get carried away.

 

I just installed the PI TC and the TRD LSD. The TC is set at 2800rpm.

In normal driving the car feels the same, except in light crusing around 40~45rpm and you let up the gas pedal, I feel a little push when the transmission upshifts from 4th to 5th gear. Before the upshift is smoother.

When accelerating from standing still and turning, I could feel the locking of the LSD. It's a bit disconcerning at first, but it beats having the wheel spin and the Traction Control cutting the power!

The power flow from the TC is phenomenal. My low end has already been improved by the SRT CAI, and now I can feel it even more. I have not done a full throttle run from standing still, but there were a couple of times where I drop the transmission to 2nd gear and power through a tight freeway on-ramp. The feeling is incredible! And no tire spinning too. The traction control was liking sleeping, never bother me once while I was having fun.

Now I need to install the transmission oil cooler.

 

All, thanks for your input!!! I have been sitting on the fence with these mods because of barrier to entry [cost] and fear of screwing up my warranty. But the taxman was kind and will be giving me some of my hard-earned money back and my 3 year warranty will be up in a few months so that will no longer be an issue.

I can't wait!!! Bwah ha ha ha ha [evil laugh]