Skrill

I was at the track today and it was danmed hot (Willow Springs about 90F ambient -- who knows what on the track).

Anyway, I was running hard and found that that as I got into my sessions my clutch pedal would get real soft, and drop to the floor as I upshifted and not come back up. This was at the top of 4th going down the front straight at well over 100 mph.

Anyway -- I would calmly pull the pedal up with my foot and proceed through the session but as the temps built up it would start happening at other areas of the track. Once I came into the pits and let thinks cool off -- it was fine. I had no issue shifting and the clutch would disengage (i.e., I had power) -- but it was extremely unnerving. Once everything was cool -- the issue went away completely. When I started out the next session -- everything would be fine, until stuff started getting hot again (about 10-15 minutes into the 25 minute session). Then the problem would come back and get progressively worse.

I remember Doug Crawford telling me that some people w/ Crawford Headers who drove their Z's really hard (like at the track) would boild their clutch fluid. I have never experienced boiled clutch fluid -- but I imagine that is what I did given that the problem when away when I cooled everything down.

I have stock clutch, flywheel and clutch fluid (which is just the stock DOT 3 brake fluid). I had no issues with slipping of the clutch at all, and no issues shifting. I had no other issues with overheating (I also have a Koyo rad, Nismo P/S cooler, and Nissan Motorsport Oil Cooler).

Engine mods as follows --

Nismo CAI
ProFlow Bored ThrottleBody
Crawford Cast Plenum
Crawford Headers
Crawford Cats
Nismo Exhaust
Technosquare Tuning

I put a call into Doug, and left a voicemail. Previously he said that people with this issue replaced the stock fluid with a higher temp fluid (like Ate SuperBlue DOT4 or Motol RBF 600) - and it solved the problem.

Any help would be appreciated.

Edit: This was the first time I tracked the car since putting on the headers. And they are coated with JetHot 2000.

amolaver

iTrader: (1)

interesting. i'd swap in some rbf or ate just because. where the heck do you bleed it from? anybody got pics or a diagram?

but the answer the question - no, i've never had anything like that happen. 'course, the hottest day i've been on track has been mid-80's ambient. probably mid-upper 90's asphalt temps.

ahm

daveh

iTrader: (9)

Keep us posted as to your findings. Putting in a better fluid would be the first course of action.