penguinking

made by longare racing, they bleed off pressure buildup on the track so tires remain at a constant pressure. wondering if anyone in the racing community uses these as this appears to be a great solution to what can be a major headache for some

http://www.longacreracing.com/catalo...d=579&catid=20

JackOlsen

I bought a set, and never took them out of the bag. Tire valve failure produces such catastophic crashes that I just didn't feel comfortable adding a link in the chain that could inadvertantly bleed off my pressures. After I looked at my set, i decided to just check my pressures after each session like everyone else does.

Greg Fishman

I'd stay away from them. This is based on what I have heard others say that are a lot more knowledgable than I.

Larry Herman

Greg, I've heard just the opposite. A fairly good racer and mechanic named Dave Coleman from Summit Point swore by them. They keep your tires at the maximum desired pressure, bleeding off the excess that would develop normally through heat. He used to start out races with his slicks at the perfect pressure and in the first two laps, rocket away from everyone, until their tires came up to operating pressure (and temperature). I never had the ***** to drill 4 holes in my rims to try them.

penguinking

is that the only thing thats keeping racers from using pressure bleeds? i first discovered this device while reading through carroll smith's "drive to win" book, thought it was a neat idea, then forgot about it until earlier htis week when i was going through the lindsay racing website and on their project car buildup they mention using the tireliefs. though on the longacre website literature their use seems to be directed towards oval track racers.

mitch236

What is to keep the bleeder from losing too much air during tire compression (bumps)

penguinking

thats a good question. i wonder how much the tire deflects going over a bump or a rumble strip, for example. i'm sure these tireliefs would be something to experiment if you have a "junk" set of rims to play around with. again, i think these are intended for oval/clay/dirt racers so they're not going over too many bumps

Greg Fishman

How accurate are they to begin with? If you set them to 40 will all tires show 40 or will there be significant variances.

penguinking

you set them individually.

i'm hoping someone whos actually uses them can contribute to the thread

RJay

And of course this would seem to make more sense, assuming it worked, for a racing venue, not a DE as you'd have to refill you tires back to optimum once they've cooled down. Although I suppose you don't have to, they could start low ( as normal) for any subsequent sessions and theoretically come up to optimum, assuming you hadn't gotten them so hot that they overbled and no longer reach your setting (like a sunny morning and a cloudy afternoon or light rain). Dunno, just seems like there are too many scenarios where even if this were bullet proof from a safety point, aside from the inital hot lap argument doesn't seem worth the effort to me. Plus they seem only to go to 38 lbs which seems a little low for some tires.

penguinking

well you did say primarily for racing, and r-compounds use lower tire pressures than regular street tires

RJay

Hoosiers R-Componds, which is what I was thinking of, particularly the 04s seem to require well in excess of 38 pounds. I've know of some people who are running with hot pressures close to 50!

Cory M

I've got a set of Panasport wheels for a 240z track car that have them. They were on the car when we bought it but they were blocked off with a bolt, I left them blocked off. If I try them out in the near future I'll give you guys an update.

Greg Fishman

I understand how you set them. My point is even if they are supposed to be at a given pressure are they really at that pressure when you check them at the valve stem.

JPhillips-998

I have a set of wheels with them but have never bothered to check their accuracy. I will do that and post the results. There was a post about these several months ago but I couldn't find it in a search.

At that time, I had questions as to "how fast they work". My concern being if you are in a long highspeed corner (carousel at Road America) you are likely heating your tires and raising your tire pressures for a short period of time. If they offer immediate relief, would you be running less than ideal pressure for the rest of the lap? Should you be able to overfill your tires on the paddock or should the pressure bleed off immediately? I have never heard mine bleeding air on the paddock so I can't say....

Another issue raised by Hoosier was that the stems tend to collect more than thier share of rubber debris during a session (as opposed to the "random" patterns that normally occurs). This could cause a significant imbalance in the wheel while on the track.

I am going to have mine removed and the holes filled before the start of the season.