Clutch replacement

Hey guys,

Newbie on the forums. I have an E92 335xi and I am looking at getting JB4, DPs, intake and exhaust this summer and noticed that virtually nobody is talking about clutch replacement on these boards.

The above mods will bring the car from ~275whp to close to 400 (if not over), so I doubt that the stock clutch can take that kind of a beating.

What brand/model clutches are you guys using and what are your impressions?

Thanks!

The stock clutch will more than handle those loads. It's the individual poor driving style that ruins clutches & added torque will accentuate that.

g/l

Originally Posted by Husband

Hey guys,

Newbie on the forums. I have an E92 335xi and I am looking at getting JB4, DPs, intake and exhaust this summer and noticed that virtually nobody is talking about clutch replacement on these boards.

The above mods will bring the car from ~275whp to close to 400 (if not over), so I doubt that the stock clutch can take that kind of a beating.

What brand/model clutches are you guys using and what are your impressions?

Thanks!

Did you own an STI/WRX before your E92?

Originally Posted by lqaddict

Did you own an STI/WRX before your E92?

Nope. I'm a Toyota man - owned a RAV4 and a couple MR2s over the past few years.

I've gotta be honest, I'm skeptical and surprised that an OEM clutch can handle a ~40-50% increase in HP/TQ.

I agree with Gary. If you jump off the line and ask the clutch to absorb all that power you'll wear it out in no time. If you ease out the clutch gently and wait until your left foot is off the pedal before smashing the accelerator, then the stock clutch will hold up just fine.

So is it safe to say that you guys are pushing 350-400whp with a stock clutch then? How many miles on it? I'd like to hear from someone who has done this.

Isn't the clutch/transmission in the 335 is the same as the one from the e39 M5, which had 400hp? Should be fine.

Don't worry about your clutch in that E92. You have a torque safety valve called limited traction. Long before you grenade your clutch your right rear tire will be doing a smoke show.

Clutch will be fine for a while, but the the vibration from the dual mass flywheel under high boost/load at low rpms will be there. I have had 2 tuned manual 335's and both clutches have been fine accept for the vibration.

Originally Posted by David1

Clutch will be fine for a while, but the the vibration from the dual mass flywheel under high boost/load at low rpms will be there. I have had 2 tuned manual 335's and both clutches have been fine accept for the vibration.

I thought dual-mass flywheels are supposed to lessen vibration in the drive train?

Originally Posted by Husband

Nope. I'm a Toyota man - owned a RAV4 and a couple MR2s over the past few years.

I've gotta be honest, I'm skeptical and surprised that an OEM clutch can handle a ~40-50% increase in HP/TQ.

The reason I asked because it is a prevalent subject among WRX/STI crowd

Originally Posted by DSXMachina

Don't worry about your clutch in that E92. You have a torque safety valve called limited traction. Long before you grenade your clutch your right rear tire will be doing a smoke show.

Is that the CDV you refer to? The one that most seem to like to delete?

Originally Posted by cwinter

I thought dual-mass flywheels are supposed to lessen vibration in the drive train?

Not once the springs get fully compressed in the flywheel.

Originally Posted by daytrader

Is that the CDV you refer to? The one that most seem to like to delete?

He isn't talking the CDV, he is saying that your tires will spin before your clutch explodes. The 335i doesn't have a locking rear diff like the M3.

Originally Posted by jburke4689

He isn't talking the CDV, he is saying that your tires will spin before your clutch explodes. The 335i doesn't have a locking rear diff like the M3.

Yeah that makes sense, lighting them up has never been much of a problem.
OK thanks, no way I would ever find my pulled CDV anyway!

Originally Posted by David1

Not once the springs get fully compressed in the flywheel.

So the benefits of this are negated once the clutch is fully dis-engaged? Seems silly to (me) to reduce rattle/noise during shifting while introducing rattle while the clutch is disengaged, considering you spend much more time in gear than out of gear shifting. Blurb from an AMS Automotive...

Dual-mass flywheels were originally developed to reduce synchronizer wear, gear noise, and chassis rattle in high-torque diesel applications like 7.3L Ford and 6.5L GM trucks. However, because dual-mass flywheels were so effective in improving shifting action while reducing noise, vibration, and harshness (NVH), they were soon adapted for use in high-performance applications including Audi TT, BMW 325, Chevy Corvette, and Porsche Boxster. Lately, dual-mass flywheels have found their way into more every-day vehicles like Acura TL, Ford Focus, Hyundai Sonata, and Nissan Altima.

http://www.amsautomotive.com/flywheels_dualmass.php

Originally Posted by cwinter

So the benefits of this are negated once the clutch is fully dis-engaged? Seems silly to (me) to reduce rattle/noise during shifting while introducing rattle while the clutch is disengaged, considering you spend much more time in gear than out of gear shifting. Blurb from an AMS Automotive...



http://www.amsautomotive.com/flywheels_dualmass.php

No, the OEM DM flywheel maxes out it's vibration dampening capability when highly tuned.