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Old 2006-03-12, 07:53 PM   #26
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Cart : Horse

Turn down your boost, and come out and drive.

You need to destroy at least one set of pads and rotors before you start worrying about brake ducts.

Did I mention seat time?

The drivers instructors fear most, and most often end up hurting their car or themselves are ones who have made many mods to their cars before they learn to drive.

I am not saying this is you, but reccomending you take things slow. You already have a fast car, use up some street tires, and stock brakes and learn to drive it the way it is. The only mod I would make before your first event is turning down your boost.

They only way to be fast is to be slow first.
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Old 2006-03-12, 10:45 PM   #27
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^Makes sense... but I'm not turning down my boost! I cant anyways... its the lowest it goes right now.
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Old 2006-03-12, 11:08 PM   #28
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Quote:
Originally Posted by Dean
You need to destroy at least one set of pads and rotors before you start worrying about brake ducts.
The good new is that without brake ducts, this won't take long

<captain stoptechs>You don't need brake ducts on your crappy stock brakes, just brake less</captain stoptechs>
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Old 2006-03-13, 07:30 AM   #29
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Quote:
Originally Posted by MikeK
The good new is that without brake ducts, this won't take long

<captain stoptechs>You don't need brake ducts on your crappy stock brakes, just brake less</captain stoptechs>
I hear that. Dont worry it's still fun, even though you won't out-brake anyone into a turn.
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Old 2006-03-13, 08:48 AM   #30
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If I'm Captain Stoptech, I never said exactly that, and I ran on my stock brakes for almost 2 years including many track days before putting on the Stoptechs.

Speak for yourself Brembo Bleeding Boy.

Learning to drive within your cars limits such as tires, suspension, cooling system, and brakes is key to learning to drive.

If you come out on R-Compounds, big brakes, and a slot car suspension, you aren't going to learn nearly as much because the car will save you right up until it snaps loose and then you won't understand why.

To misquote Days of Thunder...

You drive 20 laps your way, then 20 laps my way and we'll se which is faster, and which has more of the car left.
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Old 2006-03-13, 10:45 AM   #31
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Quote:
Originally Posted by tysonK
I hear that. Dont worry it's still fun, even though you won't out-brake anyone into a turn.
All we do are time trials and open track days... you should *never* be attempting to out brake someone into a corner. You shouldn't even be near the guy in front of you... if something goes wrong w/ their car, just like on the street, you need a buffer to allow you time to react and avoid and incident.

For example: at the RFR Audi day a while back, with an instructor in my car, we decided to practice some left foot braking through T5-T6. There was an older Jetta (IIRC) that had been tailing me for a few laps so he was pretty used to my line and was starting to follow pretty close. Well, we went into T5 and I grabbed a little more brake w/ the left foot than I intended a little earlier than normal. Of course I let up right away to get back on line, but to the guy in the Jetta it must have looks like a massive early brake check.

He still had the wheel turned exiting T4 and stomped the brakes... and we all know what happens when you turn and brake... I glanced in my mirror and saw that Jetta almost completely sideways with tire smoke billowing off the rear wheels. After the session the guy came up to me and actually apologized for tailing me so close (class act guy, it was really my fault not his) I told him I was sorry for not letting him by on the straight before trying a new line... I was just concentrating so hard on listening to my instructor and working on my driving, I plain old forgot some common courtesy.

Anyway, the moral of the story is that the guy in front of you might be an idiot like me and decide to run a new and shitty line, which can get you all sorts of out of sorts if you need to check up mid-corner to avoid them.
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Old 2006-03-13, 10:56 AM   #32
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Well, there are a couple of aspects of thermal management you need to consider. The first has been mentioned, with simple overheating.

Another is heatsoak. Depending on where intake air is routed, the piping can absorb quite a lot of heat. So after your intake air goes through the intercooler, it can be reheated by the piping. You'll feel the car essentially fall on it's face after a few laps if you're getting heatsoak. The intake charge will be too hot, the intake air density will be lower and the compy will pull timing to reduce knock.

I can't tell you the number of times I've seen IC piping go right over the turbo before it turns into the throttlebody. This is a perfect candidate for heat soak performance loss and overheating.

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Old 2006-03-13, 11:32 AM   #33
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Quote:
Originally Posted by GarySheehan
I can't tell you the number of times I've seen IC piping go right over the turbo before it turns into the throttlebody. This is a perfect candidate for heat soak performance loss and overheating.
And a perfect candidate for thermal insulation.
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Old 2006-03-13, 12:44 PM   #34
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Quote:
Originally Posted by sperry
All we do are time trials and open track days... you should *never* be attempting to out brake someone into a corner. You shouldn't even be near the guy in front of you... if something goes wrong w/ their car, just like on the street, you need a buffer to allow you time to react and avoid and incident.
Werd. Anybody have a link to Lowball's in-car from the i-club Buttonwillow day where freddie's car goes blazing by us on the straight... straight off of turn one, and almost came back on and t-boned me? Video proof that if you're not racing, you need spacing. I made that up all by myself! Go me.
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Old 2006-03-13, 02:29 PM   #35
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Time trials sound fun I'll definatly be wanting a lot of buffer room though.

Are the stock STI brakes / pads / fluid / (other components i don't know about) gonna be just fine for my first few track days ? (i'll probably be slow, but i could also be on the brakes too much ) ?
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Old 2006-03-13, 02:34 PM   #36
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I would suggest higher temp front pads and fresh fluid. You can swap the pads the night before or at the track in the morning. The rest of the bits will be fine the first few times out.
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Old 2006-03-13, 02:49 PM   #37
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Quote:
Originally Posted by GarySheehan
I can't tell you the number of times I've seen IC piping go right over the turbo before it turns into the throttlebody. This is a perfect candidate for heat soak performance loss and overheating.

Gary
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www.teamSMR.com
Hmmm, that's exactly how mine is. I'm hopeful that the big scoop is generating enough air over the turbo area to help a little.
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Old 2006-03-13, 02:51 PM   #38
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Quote:
Originally Posted by doubleurx
Hmmm, that's exactly how mine is. I'm hopeful that the big scoop is generating enough air over the turbo area to help a little.
Do you have a heat shield on your turbo? I added the generic Gruppe-S shield on my car... took all of 5 minutes to install and should help a bit. Though bagging the turbo and wrapping the intake would also help quite a bit.
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Old 2006-03-13, 02:59 PM   #39
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Quote:
Originally Posted by sperry
Do you have a heat shield on your turbo? I added the generic Gruppe-S shield on my car... took all of 5 minutes to install and should help a bit. Though bagging the turbo and wrapping the intake would also help quite a bit.

No. I should get one. I wonder if my stock one can be modified ever so slightly?
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Old 2006-03-13, 03:05 PM   #40
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Quote:
Originally Posted by doubleurx
No. I should get one. I wonder if my stock one can be modified ever so slightly?
http://www.scoobymods.com/forums/sho...09&postcount=8

If your DP is bare metal, consider wrapping that too. The DP radiates heat into the engine bay to a certain extent and holding the heat in exhaust components actually increases their performance (hotter gas travels faster).
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Old 2006-03-13, 03:19 PM   #41
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My turbo is bagged, and downpipe is wrapped. They made a huge difference to the temps on that side of the IC. Anyone who is planning on having the turbo off the car for any reason, definately consider taking the extra time to wrap the turbo hotside.
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Old 2006-03-13, 03:20 PM   #42
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Quote:
Originally Posted by cody
holding the heat in exhaust components actually increases their performance (hotter gas travels faster).
Only if it is before the turbo (headers and uppipe). The exhaust gasses don't help the turbo spool once they are past the turbo
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Old 2006-03-13, 03:22 PM   #43
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Quote:
Originally Posted by MikeK
Only if it is before the turbo (headers and uppipe). The exhaust gasses don't help the turbo spool once they are past the turbo
True. The closer to the cylinder, the more important keeping heat in is for gas velocity.
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Old 2006-03-13, 03:23 PM   #44
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Quote:
Originally Posted by cody
http://www.scoobymods.com/forums/sho...09&postcount=8

If your DP is bare metal, consider wrapping that too. The DP radiates heat into the engine bay to a certain extent and holding the heat in exhaust components actually increases their performance (hotter gas travels faster).
Close... you want to keep the heat in the exhaust before the turbo because the hotter the gasses, the more they expand, the faster the turbo spools. After the turbo, you just want to get them the hell out of there... keeping the temps up doesn't doesn't help that.

So, wrapping the DP isn't really going to gain you much, except to help reduce under-hood temps. The headers and UP on the other hand are a different matter.

Also remember, when wrapping stuff, there's pretty much a guarentee that somewhere down the road, condensation in the wrapping will eventually lead to rust destroying the wrapped exhaust. Even if you go the full 9 yards and use all the different sprays and sealants etc to make the wrapping "waterproof", you've still got a pretty good chance that the wrapping will ruin the exhaust in 5 or 6 years instead of 2 or 3. Plus, if you're going that route, it's probably cheaper and less work just to get everything jet coated.

Edit: Mike beat me to it!
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Old 2006-03-13, 03:33 PM   #45
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Yah, I'm happy with my ceramic coated UP. I don't know how much heat the wrapping on my headers really is holding in considering how hard they are to wrap well. I did use the spray sealent stuff. I would prefer to get some Port and Polished headers with a good ceramic coating, but you know, the whole money thing. I guess I'll just wait till they rust through from the wrap.
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Old 2006-03-13, 03:52 PM   #46
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Quote:
Originally Posted by GarySheehan
Well, there are a couple of aspects of thermal management you need to consider. The first has been mentioned, with simple overheating.

Another is heatsoak. Depending on where intake air is routed, the piping can absorb quite a lot of heat. So after your intake air goes through the intercooler, it can be reheated by the piping. You'll feel the car essentially fall on it's face after a few laps if you're getting heatsoak. The intake charge will be too hot, the intake air density will be lower and the compy will pull timing to reduce knock.

I can't tell you the number of times I've seen IC piping go right over the turbo before it turns into the throttlebody. This is a perfect candidate for heat soak performance loss and overheating.

Gary
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www.teamSMR.com

I've been thinking about spray-painting my Upper IC pipes with some black, high temp spray (like for bbqs or wheels) in an attempt to block off some of the heat. How would that work out?



Quote:
Originally Posted by sperry
Close... you want to keep the heat in the exhaust before the turbo because the hotter the gasses, the more they expand, the faster the turbo spools. After the turbo, you just want to get them the hell out of there... keeping the temps up doesn't doesn't help that.

So, wrapping the DP isn't really going to gain you much, except to help reduce under-hood temps. The headers and UP on the other hand are a different matter.
You just kind of ate your own words, Scott. You want to get the exhaust out as fast as possible, right? The hotter the gas is, the faster it'll move. Thus, you'll gain a little from wrapping your dp.

Also, what about high-temp spraying the DP?
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Old 2006-03-13, 04:06 PM   #47
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I've never heard of using paint to insulate piping. I bet it has negligible benefit.

And I do agree that keeping heat in the DP is not anywhere near as important as holding it in pre-turbo for turbo spool. I really don't know how beneficial the coating on my DP is considering I still have the 3rd cat right after it, but it is worth it regardless just to keep the underhood temps low and keep it from radiating heat to the TMIC.
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Old 2006-03-13, 04:19 PM   #48
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Quote:
Originally Posted by sp00ln
You just kind of ate your own words, Scott. You want to get the exhaust out as fast as possible, right? The hotter the gas is, the faster it'll move. Thus, you'll gain a little from wrapping your dp.

Also, what about high-temp spraying the DP?
Hot gasses do not "move faster", there is a difference between pressure and flow. Gasses that come off the motor are expanding due to their heat. If you let the gas cool, it doesn't expand as fast... i.e. you're losing some of the kenetic and thermal energy that will spin the turbo. Once the gas leaves the turbo, you don't want it to expand, because (just like a balloon) they expand in all directions. Expanded gasses after the turbo push backwards against the turbine blade, and slow them down. Ideally, you'd want hot expanding gas before the turbo and cool contracting gas after the turbo to help scavenge the gasses out of the turbo and reduce back-pressure.

Hi temp paint on the IC pipes will have virtually no effect. Get some thermal wrap from summit, it's relatively cheap, works well, and looks like ass under the hood (helps reduce the chances people will call you a ricer ). This is the stuff: http://store.summitracing.com/defaul...=egnsearch.asp
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Old 2006-03-13, 04:48 PM   #49
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Quote:
Originally Posted by sperry
Hot gasses do not "move faster", there is a difference between pressure and flow. Gasses that come off the motor are expanding due to their heat. If you let the gas cool, it doesn't expand as fast... i.e. you're losing some of the kenetic and thermal energy that will spin the turbo. Once the gas leaves the turbo, you don't want it to expand, because (just like a balloon) they expand in all directions. Expanded gasses after the turbo push backwards against the turbine blade, and slow them down. Ideally, you'd want hot expanding gas before the turbo and cool contracting gas after the turbo to help scavenge the gasses out of the turbo and reduce back-pressure.

Hi temp paint on the IC pipes will have virtually no effect. Get some thermal wrap from summit, it's relatively cheap, works well, and looks like ass under the hood (helps reduce the chances people will call you a ricer ). This is the stuff: http://store.summitracing.com/defaul...=egnsearch.asp
A really cool theoretical discussion on the topic of holding heat in post turbo can be found starting on page 2 of a thread sombody started on heat wrap. Here's a link: http://www.wrxfanatics.com/index.php...ot%20gas&st=15

You know it's a good discussion when people start quoting Corky Bell.

One thing Adrian (Thunderbolt) brings up is convection currents that can slow velocity if heat difuses too quickly through the pipe.
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Old 2006-03-13, 05:00 PM   #50
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Quote:
Originally Posted by sperry
... you've still got a pretty good chance that the wrapping will ruin the exhaust in 5 or 6 years instead of 2 or 3.
Wrapping makes it last 5 or 6 years instead of 2 or 3?? Where do I sign!!
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