[Chrykies]

Installed this morning at Turner Motorsport. Custom Jim Blanton-built (www.performancegearing.com) 3.46 Salisbury-style LSD with modified E60 differential cover (offering additional fluid capacity and improved cooling . . . even after removing three fins to clear the left exhaust) and factory o-ringed drain plug machined into bottom of pumpkin. Specs, review and more photos to follow, including a much-needed bath.

[nailer335]

Nice. Looking forward to a thorough review

[skim7x]

Sick bro... can't wait to hear about your experience!

[hugus311]

Originally Posted by nailer335

Nice. Looking forward to a thorough review

+1 on the new edition

[vasillalov]

E60 Diff cover! Nice I like it a lot! Hopefully the VAC and HPA will drop the outrageous prices on their E90 diff covers.

[C4sF80M3]

How do you plan on handling the speedo compensation, or are you just going to let it be off?

[JaSSon]

Same as above. Is there a way to correct the speedo? How upset will traction control be?

[onebadmofo]

E60 what, M5? Do you have P/N for the cover? I want to get the same thing for my Quaife.

[nafoo]

Any rattles when you hit bumps?

[Chrykies]

The 188L differential pumpkin used in the 335i does not utilize a differential-mounted speed sensor like some other models. Vehicle speed is derived from the ABS wheel sensors. Similarly, traction control is not affected in any way. If anything, since both wheels have traction, the traction control kicks in less to cut throttle and the DTC setting is much more forgiving as well, since one wheel is not spinning out of control while the other sits still. If you disable DSC, the car will drift and burn better than my E39 M5.

Swapping from 3.08 final drive to 3.46 final drive only multiplies torque in each gear and does not affect speedometer calibration in any way. Moving from a 3.08 to a 3.46 increases by approximately 12% the number of revolutions of the rear axle in each gear. Thus, "shortening" the final drive acts as a torque multiplier in each gear, making the car pull harder in each gear. It also requires more frequent shifting to stay within the car's boost/power band, and also reduces overall top speed.

If you are a drag racer, this diff swap is not for you, as you are concerned with maximizing speed in each gear and not losing time with gear shifts. But, if you are a daily driver that sees road track time, this mod is definitely for you. The increased torque in each gear is readily noticeable and truly enjoyable, and it actually makes 5th and 6th gear useable.

At 80mph, 5th gear runs at 3400rpm; 6th gear runs at 3150rpm. Acceleration in 6th gear is now possible without downshifting to 5th, which is very nice.

Although close, the exhaust is very tightly supported to the chassis and moves very little and does not interfere with the differential cover. The diff itself is silent and does not rattle (I am running Redline 75W-140 for initial break-in). As for clearance, I live in Boston and the roads are terrible. I am lowered on PSS10's, ride on 19" wheels and am careful to avoid raised manhole covers and steep driveway aprons. The E60 diff cover hangs only slightly lower (0.25" or so) than the factory exhaust. The E60 cover is NOT from the M5, but appears to be from a 545i or 550i. There is no complete part number on the diff cover. This diff cover does not hang nearly as low as the factory E60 M5 or E9x M3.

[Chrykies]

Notice the factory windage plate and vent pipe.

[Chrykies]

Please note that the E60 differential cover is not truly plug & play. While the bolt pattern of the cover matches that of the rear differential, the rear diff mount "ear" is backspaced off of the axle carrier bushing by approximately 16mm, which requires the fabrication of an aluminum spacer (see photo #5 above) and use of a longer bolt. I used a rear diff bolt from an E46 M3, which is about $15 from the dealer, and machined my own spacer out of 1.375" aluminum stock (Jim happened to be out of spacers at the time of my order as this cover is a special order item).

[C4sF80M3]

What's year/model/part# for that cover?

Originally Posted by Chrykies

Please note that the E60 differential cover is not truly plug & play. While the bolt pattern of the cover matches that of the rear differential, the rear diff mount "ear" is backspaced off of the axle carrier bushing by approximately 16mm, which requires the fabrication of an aluminum spacer (see photo #5 above) and use of a longer bolt. I used a rear diff bolt from an E46 M3, which is about $15 from the dealer, and machined my own spacer out of 1.375" aluminum stock (Jim happened to be out of spacers at the time of my order as this cover is a special order item).

[dlbrooks18]

Very nice, how much does this LSD cost?

[Chrykies]

Originally Posted by c4s335i

What's year/model/part# for that cover?

I presume the cover came from an E60 545i or 550i, but I cannot be certain. Realoem shows a similar cover at p/n 33 11 7 519 661, however the number stamped on my cover is 7 519 662, which realoem.com does not recognize.

[Chrykies]

Originally Posted by dlbrooks18

Very nice, how much does this LSD cost?

The base price for the build with new BMW 3.46 ring and pinion gear set is $2450, plus freight ($95) and core charge (varies depending on your needs). If you want custom lock, ramp, etc., you will need to discuss with Jim:

http://www.performancegearing.com

[dlbrooks18]

Originally Posted by Chrykies

The base price for the build with new BMW 3.46 ring and pinion gear set is $2450, plus freight ($95) and core charge (varies depending on your needs). If you want custom lock, ramp, etc., you will need to discuss with Jim:

http://www.performancegearing.com

Thanks, looking forward to a review.

[cleex024]

wow i would love to get more info on this...does anyone have this on their car yet?

[BADS335]

Actaully, putting in a shorter gear set (higher number ratio) is better for drag racing. You want more torque to accelerate and put the car in the power band when passing the traps. But it is all relative to tire diameter and traction too. My opinion is the ratios in the trans are quite short so this is really not needed. I will have to see where RPMs are when passing traps with stock ration to see if this change would bennefit at the strip. But typically, cars are geared for fuel economy so usually shorter gears give better drag times (60' and 1/4 ETs).

I look forward to review and results.

[jb's335]

I have a 3.46 in a manual car and my first gear is pointless now. And we can't do 2nd gear launches like you auto guys. Even with slicks I think I would be slower in the quarter than I was with the open 3.08.

[BMWeber]

I disagree^

I have 3.46 LSD in my Manuel and with good traction and a proper launch 2nd gear launching works great and is definitely way faster than the 3.08 non LSD launching in 1st

[cleex024]

so any update? i would love to see what you have to say about this unit as i would like to get this one too as it is a decent deal...but talked to the guy and he told me he only puts in 3 clutch packs which seems a bit low.