[mattswimmer101]

Hey F30 community,

I was just wondering if the manual trans is as strong as the auto trans in terms of reliability for bigger numbers. I know its obviously slower than auto but I'm asking if it is good for more power and if anyone has some fairly bigger numbers with the manual trans.

Thanks

[thejeremyman9]

The clutch will start to slip at low to mid 400wtq (i.e., BM3 stage 2 E30 map).

With a good clutch and flywheel the trans itself should hold 500+wtq without a problem, although your driving habits, wheel/tire setup, etc, can obviously affect that

[mattswimmer101]

Originally Posted by thejeremyman9

The clutch will start to slip at low to mid 400wtq (i.e., BM3 stage 2 E30 map).

With a good clutch and flywheel the trans itself should hold 500+wtq without a problem, although your driving habits, wheel/tire setup, etc, can obviously affect that

what exactly do you mean by driving habits lol like constantly ripping it or launching wym

[thejeremyman9]

Originally Posted by mattswimmer101

what exactly do you mean by driving habits lol like constantly ripping it or launching wym

Launching, especially if on good tires and/or a prepped surface. Any kind of shock load is hard on drivetrain parts. If you are banging gears that can fall into this category, and also wears synchro's, especially the 1-2 shift that often causes a 2nd gear grind.

Roll races with reasonable shifting is much more friendly to your drivetrain.

[XutvJet]

Originally Posted by mattswimmer101

what exactly do you mean by driving habits lol like constantly ripping it or launching wym

A 6MT won't be a good choice for you then. The 6MT in a RWD F series can handle a lot of power reliably once your upgrade the clutch. However, the 6MT syncros don't fair well if you're slamming them into gear all the time (especially the 1-2) or launching hard which is hell on a clutch and half shafts. I wouldn't recommend the 6MT if you have xdrive. It's just too much for the 6MT, especially if you're tuned.

If you want to rip shifts and are more concerned about dragging racing and 1/4 mile ET, the 8AT is the only way to go.

If you're going for a ton of power (i.e., 500wtq or more), aren't as concerned with dead stop drag racing (roll racing above 60mph is the 6MT's advantage) and want more driver interaction, the 6MT is the only way to go reliably, IMO.

[thejeremyman9]

Originally Posted by XutvJet

A 6MT won't be a good choice for you then. The 6MT in a RWD F series can handle a lot of power reliably once your upgrade the clutch. However, the 6MT syncros don't fair well if you're slamming them into gear all the time (especially the 1-2) or launching hard which is hell on a clutch and half shafts. I wouldn't recommend the 6MT if you have xdrive. It's just too much for the 6MT, especially if you're tuned.

If you want to rip shifts and are more concerned about dragging racing and 1/4 mile ET, the 8AT is the only way to go.

If you're going for a ton of power (i.e., 500wtq or more), aren't as concerned with dead stop drag racing (roll racing above 60mph is the 6MT's advantage) and want more driver interaction, the 6MT is the only way to go reliably, IMO.

Looks like we basically said the same thing at the same time haha

[codestar]

6MT xdrive here

I bought my car CPO with 29k km on it and had my trans replaced under warranty (thank the heavens) due to a bad 1-2 synchro. They said they don't do transmission repairs, only replacement. After going fbo st2 (no e30) my clutch started to slip as well.

Replaced the clutch and DMF with a spec stage 2+ and OEM flywheel, it's been running great ever since

Out of the 7 manual trans cars i've owned previously this is the only one that's given me problems with either the clutch or transmission. I can't speak much for the transmission because I don't know how the previous owner drove it, but the new one has not given me problems since. The clutch was expected with the extra power and xdrive, but I think what sped its wear along was the CDV. With the more robust clutch and CDV removal it's been great

[thejeremyman9]

Originally Posted by codestar

6MT xdrive here

I bought my car CPO with 29k km on it and had my trans replaced under warranty (thank the heavens) due to a bad 1-2 synchro. They said they don't do transmission repairs, only replacement. After going fbo st2 (no e30) my clutch started to slip as well.

Replaced the clutch and DMF with a spec stage 2+ and OEM flywheel, it's been running great ever since

Out of the 7 manual trans cars i've owned previously this is the only one that's given me problems with either the clutch or transmission. I can't speak much for the transmission because I don't know how the previous owner drove it, but the new one has not given me problems since. The clutch was expected with the extra power and xdrive, but I think what sped its wear along was the CDV. With the more robust clutch and CDV removal it's been great

This is par for the course essentially, especially when the first owner beats on it. Just do a search and you will see tons of threads about the 1-2 shift grind due to people banging gears aggressively. And as mentioned, its a trans replacement not repair. The CDV delete is also common and generally recommended for a tuned car when doing a clutch upgrade.

[Boostedphil698]

Out of curiosity, is the 6MT a GM box or ZF?

[akgambino]

Originally Posted by 435i_Phil

Out of curiosity, is the 6MT a GM box or ZF?

ZF

[zinner]

my clutch started slipping with a PS2 upgrade and I am not hard on it. I am very nice to my clutch.

[thejeremyman9]

Originally Posted by zinner

my clutch started slipping with a PS2 upgrade and I am not hard on it. I am very nice to my clutch.

Stock clutch will only hold mid 400s wtq even if its in good shape. That's why it starts slipping with BM3 stage 2 E map. The way torque shoves in hard with overboost at low rpm/high load is too much, and the disk+clamping force just cant hold it. A clutch that is beat on will just do it sooner/more severely.

[Salty B.]

My 6MT was replaced under warranty for faulty 2nd gear synchro at only 22K miles, and I don't beat on it or speed-shift, but I do enjoy a nice WOT blast up an on-ramp. Or two.

The replacement even catches a grind here and there on 1-2 and 3-2 shifts but not as bad as the original. Got a new clutch out of that too.

This ZF box seems pretty fragile. I've never, out of all the manuals I've owned in this lifetime, had a transmission failure. Clutches, sure.

Thinking of a JB4/BM3 tune this year, but nothing crazy... Between the MPPK and the Dinantronic Sport I'm not sure it's worth that kind of coin for maybe another 40hp.

[rjd_F30]

Just to add another point of reference, I lost reverse on my 6MT at 86k miles. This was like a week after I bought the car so I can't speak towards the previous owner's driving habits, though I don't imagine he was powershifting reverse very frequently. Got a reman unit under warranty thankfully. As far as powerholding I think the 6MT is reasonably robust, but it doesn't seem like the most reliable gearbox out there as far as lasting the life of the car goes.

[thejeremyman9]

Originally Posted by Flying Badger

My 6MT was replaced under warranty for faulty 2nd gear synchro at only 22K miles, and I don't beat on it or speed-shift, but I do enjoy a nice WOT blast up an on-ramp. Or two.

The replacement even catches a grind here and there on 1-2 and 3-2 shifts but not as bad as the original. Got a new clutch out of that too.

This ZF box seems pretty fragile. I've never, out of all the manuals I've owned in this lifetime, had a transmission failure. Clutches, sure.

Thinking of a JB4/BM3 tune this year, but nothing crazy... Between the MPPK and the Dinantronic Sport I'm not sure it's worth that kind of coin for maybe another 40hp.

Not to go off topic in this thread, but BM3 or MHD will be miles ahead of MPPK+sport piggyback. Not only in peak # gain, but overall driveability and power delivery. Especially if you add XHP.

Originally Posted by rjd_F30

Just to add another point of reference, I lost reverse on my 6MT at 86k miles. This was like a week after I bought the car so I can't speak towards the previous owner's driving habits, though I don't imagine he was powershifting reverse very frequently. Got a reman unit under warranty thankfully. As far as powerholding I think the 6MT is reasonably robust, but it doesn't seem like the most reliable gearbox out there as far as lasting the life of the car goes.

Yeah, that's what i was getting at. It can hold power (you wont go stripping/breaking gears), but the syncros and other bits can be failure/wear points.

[codestar]

Originally Posted by thejeremyman9

Not to go off topic in this thread, but BM3 or MHD will be miles ahead of MPPK+sport piggyback. Not only in peak # gain, but overall driveability and power delivery. Especially if you add XHP.



Yeah, that's what i was getting at. It can hold power (you wont go stripping/breaking gears), but the syncros and other bits can be failure/wear points.

on the first point jeremyman is definitely right; I purchased MPPK and a dinan stage 1 tuner before bm3. Definitely a noticeable upgrade, but the difference between stock -> mppk/dinan and mppk/dinan -> bm3 + downpipe is drastic. You could certainly feel the power upgrade over stock for the first setup, but there is a way larger power gain from the already upgraded setup to bm3. Also since that guy is mentioning synchros in his 6mt I don't think xhp is an option

My clutch seemed to be fine with just the mppk and piggyback but that was after getting my transmission replaced because of the syncho. I think that setup is right at the edge of the clutch's limit though, because it started to slip a month or two after upgrading to bm3

[thejeremyman9]

Originally Posted by codestar

on the first point jeremyman is definitely right; I purchased MPPK and a dinan stage 1 tuner before bm3. Definitely a noticeable upgrade, but the difference between stock -> mppk/dinan and mppk/dinan -> bm3 + downpipe is drastic. You could certainly feel the power upgrade over stock for the first setup, but there is a way larger power gain from the already upgraded setup to bm3. Also since that guy is mentioning synchros in his 6mt I don't think xhp is an option

My clutch seemed to be fine with just the mppk and piggyback but that was after getting my transmission replaced because of the syncho. I think that setup is right at the edge of the clutch's limit though, because it started to slip a month or two after upgrading to bm3

Oops yeah, XHP wont apply if he is 6MT. But the other comment on the tunes remains

Stock clutch can usually handle pump gas OTS maps from BM3 without a problem, but typically starts to slip on ethanol map, even if its healthy.