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Old 05-07-2013, 03:02 PM   #1
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Default shifting issue when car gets hot on track

my transmission 6 speed has a hard time shifting once it gets hot, only starts happening after nearly 20 minutes. it starts getting very hard to find 5 gear. I wonder if this could have something to do with the clutch overheating? and not fully disengage? does not seem likely. Ive tried several different oils, right now I have amsoil 75-90 trans oil. I think I need to build a heat shield for the exhaust and or add a temp probe to see what temp this trans gets to on the track.


can I put a temp sensor in the fill plug of the transmission? the drain plug has a magnet and i would rather not delete it. I'm sure the oil is splashing around inside but not sure how much of an affect it will have. guess I should not worry about the magnet since I change the oil pretty offten


any ideas or suggestion?

Last edited by psreynol; 05-07-2013 at 03:36 PM.
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Old 05-07-2013, 03:13 PM   #2
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I had a similar issue with a slow leak on the slave cylinder. Shifting would get harder about 10-15 min into a session. Downshifting was horrible, it just felt like it was not dis-engaging. My guess is that the old piston seal would warm up and leak more when hot. Never had a problem at normal street temperatures.

Do you have a hard time with all gears or just 5th?
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Old 05-07-2013, 05:29 PM   #3
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actually 5th is by far the biggest issue for me. its like once the trans is hot the shifter gets stuck on the gate for reverse or something and you must put the shifter in exactly the right spot or it will not go, versus pretty easy shifting all around at the beginning of the session.

I replaced my master and slave very recently so unless I got a bad one seems unlikely that is my problem. my down shifting is pretty fine.
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Old 05-07-2013, 06:39 PM   #4
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I got the same problem with my 6speed. I am going to try making a heat shield to separate the exhaust heat from the trans. I have to believe it's just the trans getting hot.
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Old 05-08-2013, 01:40 AM   #5
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[QUOTE=k24madness;1009632]I got the same problem with my 6speed. I am going to try making a heat shield to separate the exhaust heat from the trans. I have to believe it's just the trans getting hot.[/QUOTE


good so I'm not the only one with this issue. well we need to get cracking on this issue, I dont want to destroy my trans.

I've been thinking about the possibility of using a heavy oil or even a oil cooler but if a heat shield works that is a much better solution

I have some material that will make a good heat shield but I would like to double insulate somehow so that when I track, it is the best heat shield i can make. it kinda sucks, no way to reproduce the heat on the street.
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Old 05-08-2013, 02:19 AM   #6
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I just put this on my car today, it's from Thermo Tec...




Clamp-On Heat Shield - pretty easy to put on. My problem is that I'm getting heat soak into the footwell after about 45 min. of freeway driving to/from the track. It's just on the borderline between uncomfortable and slightly painful.

The intention is for this to block the radiant heat while still allowing the exhaust gases to cool enough so the cat doesn't overheat. I've got it on the first part of the exhaust pipe after the downpipe turns towards the rear. I'm also going to do some sort of insulating (this or self adhesive sheet on the tub) where the downpipe passes near the vertical front part of the footwell.

I did change my trans oil over the weekend and it did have a sort-of burned smell to it. Makes sense the trans is getting baked too. Hopefully this helps that as well.
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Old 05-08-2013, 02:51 AM   #7
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[QUOTE=billybobster;1009753]I just put this on my car today, it's from Thermo Tec...




Clamp-On Heat Shield - pretty easy to put on. My problem is that I'm getting heat soak into the footwell after about 45 min. of freeway driving to/from the track. It's just on the borderline between uncomfortable and slightly painful.


yeah I know what you mean, sometimes I get stuck in traffic around Chicago and between my shoes literally melting, and my seat, I would say it is borderline brutal

I mounted a cutting board to the floor and it helped a ton! now it is hardly noticeable.
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Old 05-08-2013, 09:40 AM   #8
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This is the **** you want for heat shield material. Heat Master Shields
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Old 05-09-2013, 09:02 AM   #9
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Quote:
Originally Posted by Leafy View Post
This is the **** you want for heat shield material. Heat Master Shields
that stuff looks very nice. at the moment I'm not quite ready to spend $200 on a heat shield. gotta at least try a home brew something first.

might try finding something at the pick and pull or perhaps this product is adequate

http://www.blowbyracing.com/heardopish12.html

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Old 05-09-2013, 10:53 AM   #10
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I got a sheet of this for the transmission tunnel:
DEI 050501 2' x 21" Floor and Tunnel Shield - 3.5 sq. ft : Amazon.com : Automotive DEI 050501 2' x 21" Floor and Tunnel Shield - 3.5 sq. ft : Amazon.com : Automotive

Just wipe it down to get the dust/grease off, and slide it up under there. It works really well in helping keep the heat out.

Stole the idea from this guy, cheesy vids, but great info:
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Old 05-10-2013, 01:31 PM   #11
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that looks way better than the crap I found at auto zone.

going to try to wrap the exhaust this weekend and hopefully it works. annoying that I can never test this stuff on the street since the car wont get hot enough but such is life.
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Old 05-10-2013, 03:04 PM   #12
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Put car on jack stands. Put brick on throttle. Win (or more likely lose)
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Old 05-10-2013, 04:48 PM   #13
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Even the stock exhaust has heat shielding to protect the transmission from the heat. If you are making twice as much power as stock, you are making roughly twice as much heat because you are burning twice as much fuel. I used a cheap IR thermal gun to determine how hot my trans and diff were getting immediately after track sessions and it was scary!

I used exhaust shielding form various sources (junkyard truck exhausts are 2.5-3 inches in diameter) and attached the pieces with worm gear radiator hose type clamps. It cinches down tight and worked well. Sometimes I doubled the clamps together to make them long enough to go around.

I also used the Frost King self-adhesive foam-backed aluminum that is used for home ductwork on the underside of my footwell and part of the tunnel closest to the downpipe and exhaust. After a little cleaning with solvent, it stuck quite well. I bought it at Lowe's. 15 feet by 12 inches for $18. My feet and legs are happier.

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Old 05-16-2013, 09:29 PM   #14
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just ordered 2 of the Thermo-Tec Clamp-On Exhaust Pipe Heat Shield 6" x 24" #11620 inch heat shields for pretty cheap on ebay. easy to work with and should be enough to show heat off the exhaust is causing the shifting problems when hot.. or not. perhaps the turbo itself needs a blanket. one step at a time.
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Old 05-17-2013, 02:14 AM   #15
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I just returned from a three day track weekend at Thunderhill and got a chance to test my Thermo Tec shields. One went over the downpipe at the bottom and the other on the forward part of the exhaust in the tunnel near the front of the footwell. A little fiddly to put on but a lot easier (I suspect) than trying to get self adhesive sheets in there without removing the exhaust.

My problem was not on track but on the freeway. So my left foot actually felt less heat at 90-95 degrees in the Central Valley last weekend than it did at 65 degrees in Salinas after Miatas at MRLS.

But there's still a ton of heat coming in the cabin overall - so more insulating to do.
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Old 05-17-2013, 04:10 AM   #16
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Quote:
Originally Posted by billybobster View Post
I just returned from a three day track weekend at Thunderhill and got a chance to test my Thermo Tec shields. One went over the downpipe at the bottom and the other on the forward part of the exhaust in the tunnel near the front of the footwell. A little fiddly to put on but a lot easier (I suspect) than trying to get self adhesive sheets in there without removing the exhaust.

My problem was not on track but on the freeway. So my left foot actually felt less heat at 90-95 degrees in the Central Valley last weekend than it did at 65 degrees in Salinas after Miatas at MRLS.

But there's still a ton of heat coming in the cabin overall - so more insulating to do.

good info. i dont care if my foot is on fire driving to the track, it already is. I want something that keeps my temps consistent and my trans shifting right for 20 min at full tilt... at a bare minimum, really it needs to work for an hour but right now i dont really care about hot foot. want my car running good first..

i hear you though, its kinda annoying for the street kids
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Old 05-17-2013, 08:25 AM   #17
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Quote:
Originally Posted by psreynol View Post
good info. i dont care if my foot is on fire driving to the track, it already is. I want something that keeps my temps consistent and my trans shifting right for 20 min at full tilt... at a bare minimum, really it needs to work for an hour but right now i dont really care about hot foot. want my car running good first..

i hear you though, its kinda annoying for the street kids
Its easier to be fast when you're comfortable, you might as well kill 2 birds with one stone if you're already going to be installing heat shield.
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Old 05-17-2013, 10:32 AM   #18
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My downpipe is also wrapped with header wrap to keep the heat down.
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Old 05-17-2013, 12:18 PM   #19
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Quote:
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My downpipe is also wrapped with header wrap to keep the heat down.
yeah mine downpipe is wrapped but it is not enough to keep the heat off the transmission.
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Old 05-17-2013, 04:50 PM   #20
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comfort is grand, but I dont think about comfort at all when I'm driving on the track. I think alot about comfort on my way to and from the track because my car is the least comfortable car I've ever driven.


or as Hustler said once to someone who was not having the turbo stud problem..."or maybe you're just driving like a *****. Seriously. Do you go out there for blood or to cruise around and "have fun"? I go to the track because my mother never loved me and I never met my father, and now you have to ******* respect me or I'll wear your face as a ******* mask.
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probably the funnest quote ever about track driving because it is so f-in true.
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