Since I went with the H/C package and also changed over to the C6 shifter I have noticed a problem shifting gears when racing at the 1/4 mile. At Pocono Long track I had no issues, but since last night was the 2nd time I ran the 1/4 since the Mods and had an issue I wonder what is up.


So here is the scenario:

I run a few runs with no issues. I get good shifts and everything is fine. I then get to about the 3rd run and I start to miss 2nd gear. I just cannot get it into gear.

Last night something new happen during the 5th run. I got my shift into 2nd, but I swear I could not move the shifter into 3rd. It was locked there. The clutch was in, but it would not move. Thinking aobut it over nioght I am not sure if it was locked in 2nd or stuck between 2nd and 3rd, but I know I could not move it. I then pushed teh clutch in a few times and it went into 3rd with no problem.

I stopped after that and let the car rest for about 1/2 hour. I drove home with no issues being able to shift into all gears though I could not really run the gears to see if there was an issue.

Just wondering if it is me, the shifter, something else that is starting to go, maybe time for a new tranny, syncros are out and when they heat or at high rpms they have problems (high rpms would explain why I don't have issues at the road track - I assume heat wise it would be hotter at the road tracks).

Any ideas???

 

sounds like a heat issue .. possibily the slave cylinder.

 

I would give some Royal Purple Syncor-Max trans fluid a try, I was at Fontana last year and some of those guys turned me on to RPSM, this stuff is real slippery, I could tell the difference on the first shift. What do you have to loose, 4 bottles of trans fluid.

 

good idea. I can do that at home so that is an easy one!!!

 

I haven't had this happen to me although I know several others with the same scenario and they've tried everything with no luck. The synthetic tranny fluid is a good idea as you will definitely feel the difference in shift smoothness. I'd have to say this is a heat related issue that affects the slave cylinder. The new style 'concentric' slave cylinders that are used in a lot of new vehicles have caused many headaches, especially when it comes to bleeding them. In high performance use they really start to cause problems. Off hand I'd say that there is an expansion issue occurring when they get hot that causes the fluid to bypass internally, reducing the required pressure needed to move the cylinder forward enough to release the clutch. Manufacturing tolerances could be a little on the high side for some units which causes this issue to appear. These units are partially made out of plastic. I'd be curious to know what the C6R race cars use. If you could insulate the cylinder some how with a heat protective product that might do the trick.

 

Good stuff. I use RP too and noticed a smooth change right away.
I used Royal Purple Max-ATF in my car but Synchromax is great stuff too.

Synchromax
Max-ATF

 

Bob, get an A4...