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Question about slowing down after traps

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Old 11-16-2001, 09:12 AM
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Default Question about slowing down after traps

Ok, I'm still fairly new to the drag strip so bear with me. After you run through the traps, you'll be in 4th (for most of us). My question is do you leave it in fourth and let the engine braking slow you down? Or do you stick it 6th and feather the brakes? At the track I've gone to the only way I can slow down in time is to really get on the brakes (or else I run out of room and off the track). Is it bad to let the engine slow you down in 4th gear?

Chris
Old 11-16-2001, 09:43 AM
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Default Re: Question about slowing down after traps

Most tracks that I have run on have a sufficient enough shut down area that you don't really need to get on the brakes too hard. Even still, I would leave it in 4th gear after the run and let the engine help me slow down, then just before the turn off at the end I would feather the brakes as needed.
Old 11-16-2001, 09:49 AM
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Default Re: Question about slowing down after traps

Yeah, that's really my question, if I'm going over a 100mph in 4th, is it okay to just take your foot off the pedal and let the engine slow you down? Even on the street after passing someone. Does it hurt the engine at all?

Chris
Old 11-16-2001, 09:55 AM
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Default Re: Question about slowing down after traps

It doesn't hurt the engine at all, in fact it may help it since it brings oil up into the upper cylinder area. I do know that when you're breaking in a new engine they recommend coasting like this.
Old 11-16-2001, 10:00 AM
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Default Re: Question about slowing down after traps

[quote]Originally posted by Patman:
<strong>It doesn't hurt the engine at all, in fact it may help it since it brings oil up into the upper cylinder area. I do know that when you're breaking in a new engine they recommend coasting like this.</strong><hr></blockquote>

Ok, thanks man, that's all I needed to hear. When I pass someone on the street it's usually in 3rd and ends up in 4th and then I let off the gas to slow down. If I put it in 6th and let off it just takes to long to slow down because it's such a tall gear there's almost no drag. Same for the track.

Chris
Old 11-16-2001, 10:03 AM
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Default Re: Question about slowing down after traps

Technically engine braking is hard on the engine. It should not be made a habit of, but moderate amounts don't hurt.

It puts high load on the rods, turning the engine into essentially a vacuum pump. It tries to stretch the rods.

Also very high oil consumption occurs.
Old 11-16-2001, 10:07 AM
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Default Re: Question about slowing down after traps

[quote]Originally posted by McRat:
<strong>Technically engine braking is hard on the engine. It should not be made a habit of, but moderate amounts don't hurt.

It puts high load on the rods, turning the engine into essentially a vacuum pump. It tries to stretch the rods.

Also very high oil consumption occurs.</strong><hr></blockquote>


So after you blow by someone on the road do you just throw it in 6th and coast back down to a cruising speed?

Chris
Old 11-16-2001, 11:12 AM
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Default Re: Question about slowing down after traps

MI_SS_LE,

If you are going to Luskville, they have a VERY short run off area for a 1/4 mile track. Especially if you want to hit the first exit from the run off area. I usually keep on the gas until I am sure I am clear of the traps, then I brake moderately hard and downshift. I don't think that you would do much damage by either braking hard or letting the engine brake you down, unless you slam it from 4th to 1st! <img src="images/icons/shocked.gif" border="0">
Old 11-16-2001, 11:27 AM
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Default Re: Question about slowing down after traps

[quote]Originally posted by BBYZED:
<strong>MI_SS_LE,

If you are going to Luskville, they have a VERY short run off area for a 1/4 mile track. Especially if you want to hit the first exit from the run off area. I usually keep on the gas until I am sure I am clear of the traps, then I brake moderately hard and downshift. I don't think that you would do much damage by either braking hard or letting the engine brake you down, unless you slam it from 4th to 1st! <img src="images/icons/shocked.gif" border="0"> </strong><hr></blockquote>

That's exactly where I'm talking about. The end of the track is so close to the traps I have to really get on the brakes to make the turn. Usually I leave it in fourth and get on the brakes as lightly as I can.

Chris

P.S. BBYZED, sorry to see you go from M.R.'s. You should have given it more of a chance. It's local at least.
Old 11-16-2001, 11:30 AM
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Default Re: Question about slowing down after traps

[quote]Originally posted by MI_SS_LE:
<strong>


So after you blow by someone on the road do you just throw it in 6th and coast back down to a cruising speed?

Chris</strong><hr></blockquote>

After a 1/4mi pass, I push the clutch in and brake. I have a better feel for what the car is doing with the clutch in. Our turnout (1 only) is only a few hundred feet from the finish, you have to brake aggressively or do a Uturn on the track. My first few passes, I had to do a UTurn.

With big fronts, it's not so much of a issue, because these cars have SERIOUS braking power. With skinnies, it's a little fussier.

On the street, I usually go to 6th.
Old 11-16-2001, 11:42 AM
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Default Re: Question about slowing down after traps

I have heard that engine breaking is hard on the engine and the bearings. I put my car into OD as soon as I go thru traps.
Old 11-16-2001, 11:52 AM
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Default Re: Question about slowing down after traps

I usually back out of the gas and let it slow on it's own for just a bit, then pop it in neutral and start hitting the brakes...I do always go to the very last turn off.....I don't feel letting the RPM's hang in there for a while is that good for it...as McRat stated most oil consumption is attributed to RPM's over 3K alot.
I have slotted rotors now and they seem fine w/ new pads...afterall, might use up more pads.....it's cheaper to me to use my brakes hard then be hard on the motor more then alot of WOT runs! <img src="images/icons/grin.gif" border="0">
<img src="images/icons/smile.gif" border="0">
Old 11-16-2001, 01:06 PM
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Default Re: Question about slowing down after traps

FWIW, i always pop it out of gear when i pass the traps and use the brakes only.

I get the ABS to kick in when the skinnes are on. I can hear the slip and grab <img src="images/icons/smile.gif" border="0">

the first few times i left it in gear and it was harder to stop.

and some advice, make sure your brakes are good and burnished after a pad change. the time to seat them is not right after crossing the traps at 128 <img src="images/icons/shocked.gif" border="0"> <img src="images/icons/grin.gif" border="0">

don't ask how i know <img src="images/icons/wink.gif" border="0">
Old 11-16-2001, 01:20 PM
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Default Re: Question about slowing down after traps

[quote]Originally posted by y2khawk:
<strong>and some advice, make sure your brakes are good and burnished after a pad change. the time to seat them is not right after crossing the traps at 128 <img src="images/icons/shocked.gif" border="0"> <img src="images/icons/grin.gif" border="0">

don't ask how i know <img src="images/icons/wink.gif" border="0"> </strong><hr></blockquote>


<img src="images/icons/rolleyes.gif" border="0"> Mr. "What? They have a lifetime warrenty!"


I push in the clutch, and get on the brakes.
Old 11-16-2001, 01:22 PM
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Default Re: Question about slowing down after traps

[quote]Originally posted by blackhawk2000:
<strong> <img src="images/icons/rolleyes.gif" border="0"> Mr. "What? They have a lifetime warrenty!"
</strong><hr></blockquote>

ahem, i need it <img src="images/icons/tongue.gif" border="0">


Old 11-16-2001, 01:27 PM
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Default Re: Question about slowing down after traps

[quote]Originally posted by y2khawk:
[qb]

ahem, i need it <img src="images/icons/tongue.gif" border="0">

<hr></blockquote>

Holy cow, do you ever need it <img src="images/icons/grin.gif" border="0"> How in the hell did you do that?

Chris

[ November 16, 2001: Message edited by: MI_SS_LE ]</p>
Old 11-16-2001, 01:38 PM
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Default Re: Question about slowing down after traps

[quote]Originally posted by MI_SS_LE:
<strong>

Holy cow, do you ever need it <img src="images/icons/grin.gif" border="0"> How in the hell did you do that?

Chris

[ November 16, 2001: Message edited by: MI_SS_LE ]</strong><hr></blockquote>

LOL

that actually happened when i stood on it at 140 to make a turn on the highway w/ ET streets
out back. The 929RR next to me was doing the same <img src="images/icons/grin.gif" border="0">

I've been told i shoot massive sparks from the front brakes when i stop from speed. those silly semi-metallic pads <img src="images/icons/smile.gif" border="0">
Old 11-16-2001, 02:13 PM
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Default Re: Question about slowing down after traps

I do not upshift most of the time. With our cars manually upshifting will allow you to wind out a shift, but not shortshift.

When you have as much gear as I do (4.10's in an A4) It's nice to shift into OD... I like my engine. <img src="images/icons/smile.gif" border="0">
Old 11-16-2001, 02:23 PM
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Default Re: Question about slowing down after traps

[quote]Originally posted by Pro Stock John:
<strong>I do not upshift most of the time. With our cars manually upshifting will allow you to wind out a shift, but not shortshift.

When you have as much gear as I do (4.10's in an A4) It's nice to shift into OD... I like my engine. <img src="images/icons/smile.gif" border="0"> </strong><hr></blockquote>

Then in an M6...I guess pop it in neutral, coast til we have to lay into the brakes!!
Old 11-16-2001, 02:37 PM
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Default Re: Question about slowing down after traps

[quote]Originally posted by Pro Stock John:
<strong>I do not upshift most of the time. With our cars manually upshifting will allow you to wind out a shift, but not shortshift.

When you have as much gear as I do (4.10's in an A4) It's nice to shift into OD... I like my engine. <img src="images/icons/smile.gif" border="0"> </strong><hr></blockquote>

So does this mean the computer actually shifts a little too early? Is that because of the 4.10's or are the shift points just not set right to the end of the rpm range on a stock A4 car? I thought the A4 shifted pretty well when putting the pedal to the floor and holding it. It feels like it winds the gear right out. ????

Now, as to the original question ... so far I've gotten leaving it in 4th is ok and letting the engine brake, push the clutch pedal in and hold it and coast, put it in neutral and coast (and brake), put it in 6th. Looks like everyone has their own style. As long as I know I'm not doing damage to the car I'll use whatever feels best I guess.

Chris


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