[leftcoastman]

Went to the drag strip for the first time yesterday. I'm normally a twisties guy so it was definitely a new experience to launch and just drive straight!

Out of the three runs I did, I blew my 1-2 shift in two of the runs! I somewhat forcefully move it into second at about 6000 rpms (didn't shortleg the clutch) and while the lever goes there, the gear doesn't engage.

What gives? If I gingerly put it into second, it engages just fine. But when I'm trying to shift quickly, a ginger shift just doesn't seem effective. What causes missed shifts and more importantly, how do you avoid them?

BTW - I'm in a 335i with 6MT and about 8000 miles.

[razormy]

It's the clutch delay valve. It does not matter how fast you will try to shift, the CDV will only allow the fluid to move through it at it's rate.

Once you remove it, you will love your 6MT.

[SoCal335i]

what was your best time?

[ADHD]

ya do the cdv mod and youll be golden!!!!

shifting from 2 to 3 for me on teh drag strip is where i usually miss!!

[leftcoastman]

CDV has been removed already. And it's only my 1-2 shift. My 2-3 and 3-4 are no problem.

[leftcoastman]

Originally Posted by SoCal335i

what was your best time?

The track is at 6,000 ft. Guess my time and trap speed.

[PresaMat]

Leftcoast - does it feel like your in gear pressing down the gas but the car isnt really going anywhere? Ive had this happen to me... gotta love shitty bmw clutches.

[leftcoastman]

Originally Posted by PresaMat

Leftcoast - does it feel like your in gear pressing down the gas but the car isnt really going anywhere? Ive had this happen to me... gotta love shitty bmw clutches.

I guess you could say that. The lever is in the "2" position but when you engage the clutch (foot off clutch pedal), the engine just revs. A textbook missed shift.

Presa - do the CDV delete. Never understood the bored out CDV. If your tranny blows, would you want to bank your warranty on BMW not peeking into the modified Zeckenhausen CDV? Or would you rather take 2 seconds and put the original CDV back in?

[Maestro]

I have experience this too.

I have not been able to pin point exactly what causing this. Every once in a while, trying to hit second coming out of first it just does not engage it kind of sticks, something it misses totally other times it grines, and some times it partially engages and when you let the clutch you can feel the shifter fully engage. However, if you do not leave your hand on the shifter it will pop out.

It happen going 2nd to 3rd some times too, but not as ofter, but never happens doing a down shift. I am thinking something is messed up with the synconizer.

I never missed as many time as I have with this car, and I do believe the CDV has a little to do with it, but some times I really have to pull hard to get it into 2nd.

[HyperM3]

I firmly believe the syncros are off on the 1-2 shift. No matter how many people have the CDV, modded it, or deleted it, theres still a problem shifting fast. Going into any of the other gears 3-6 quickly isnt a problem. I still grind 2nd sometimes and I dont know why. The clutch is all the way down but its like it doesnt want to engage as quickly.

Id rather this than my fuel pump dying if theres a choice.

[PresaMat]

Could a SSK help with this?

Mat

[HyperM3]

Originally Posted by PresaMat

Could a SSK help with this?

Mat

Maybe, but theres nothing officially made for our 6spd yet. From what I understand the B&M one has some fitment issues. Ill wait for Rogue or UUC to come out with theirs and then decide.

[schneid4323]

this is getting interesting. I have the CDV delete. But for some reason at higher revs, the car hates goign from 1st to 2nd, it almost forces me outta the gear, hell ill even put the lever in gear and sometimes you will hear grinding. So this is a comon issue?

[mayno]

Get the steptronic....problem solved. j/k

You need to put some force/effort in changing your gears quickly...don't baby it...you won't break anything so don't worry. in my previous car (2003 M3), it supposedly had the CDV but I never had a problem doing very quick shifts.

[schneid4323]

Originally Posted by mayno

Get the steptronic....problem solved. j/k

You need to put some force/effort in changing your gears quickly...don't baby it...you won't break anything so don't worry. in my previous car (2003 M3), it supposedly had the CDV but I never had a problem doing very quick shifts.

Were talking ALOT of force then, its horrible

[HyperM3]

Originally Posted by schneid4323

this is getting interesting. I have the CDV delete. But for some reason at higher revs, the car hates goign from 1st to 2nd, it almost forces me outta the gear, hell ill even put the lever in gear and sometimes you will hear grinding. So this is a comon issue?

Yes.

[radgator1]

Originally Posted by leftcoastman

The track is at 6,000 ft. Guess my time and trap speed.

14.1@101.

Okay now post the timeslip or Ban . You already have your excuses covered with the elevation and shift problems.

[derryck]

in my previous car (2003 M3), it supposedly had the CDV but I never had a problem doing very quick shifts.

I have an 03 M3 (6MT) and an 07 335i (6MT) and the trannies are completely different. The M3 is always kinda notchy unless I'm running the gears hard and then it's smooth as silk. I have not done the CDV delete in either car and don't really see a need to as of yet. I should get the 335i to Gainesville in the next month or so and I'll see if I change my mind.

[bronco]

slip?

[jack1526]

i've had this problem before, but once i did the modified CDV, in my case.....my shifting has became not only smoother but quicker throughout all the gears...

[leftcoastman]

Originally Posted by radgator1

14.1@101.

Okay now post the timeslip or Ban . You already have your excuses covered with the elevation and shift problems.

Close. The slip is at home. 14.6 @103.5

I'm going back next week. Twas my first time at a drag strip. I'm thinking mid 13s with a proper launch. Hell I'd be super stoked to get 13.9x that here at 6,000 feet. Might even try starting in 2nd since the track is a bit slick.

BTW - I have found that finger-shifting (gentle) is less likely to cause a missed shift than palm-shifting (forceful).

To be honest, the challenge of properly launching a 6MT is appealing to me. No grandma-appropriate 6ATs here! Just kidding, fellas.

[radgator1]

Originally Posted by leftcoastman

Close. The slip is at home. 14.6 @103.5

I'm going back next week. Twas my first time at a drag strip. I'm thinking mid 13s with a proper launch. Hell I'd be super stoked to get 13.9x that here at 6,000 feet. Might even try starting in 2nd since the track is a bit slick.

BTW - I have found that finger-shifting (gentle) is less likely to cause a missed shift than palm-shifting (forceful).

To be honest, the challenge of properly launching a 6MT is appealing to me. No grandma-appropriate 6ATs here! Just kidding, fellas.

Pretty decent trap speed. It should allow lots of room for improvement in the ET. What was your 60'. 2.5 or so I'm guessing.