Drag Racing Technique Improve your track times

What's your trap RPM ?

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Old 08-07-2009, 06:37 AM
  #31  
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Originally Posted by 5SPDCHK
I never really understood the whole +X% thing until I started driving my own car. I used to sit in the stands up at the top end and wonder why the shift light was on in most cars while going through the traps. The first time I ran my car I thought I broke something because my shift light was on and I had no more gears left... DUH!!!

Yes! That very first time down the track in a car with the shift light coming on before you've reached the first speed cone, makes you wonder if you "can" or "should" stay in it until you reach the stripe!

Due to some local and division politics and a few other issues, we're running 1/8 mile this season in the NHRA Summit Bracket points series. So, I don't have to worry about the shift light being on in my new tube-chassis car this season. However, we have a perfectly good 1/4 mile track that hosts a Div-4 Lucas Oil event.

If I recall correctly, I believe you wrecked your car about two years ago. I hope you've got everything back together and are back at the track racing again.

WD

Last edited by The Engineer; 08-07-2009 at 06:39 AM.
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Old 08-07-2009, 07:30 AM
  #32  
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Originally Posted by The Engineer
Yes! That very first time down the track in a car with the shift light coming on before you've reached the first speed cone, makes you wonder if you "can" or "should" stay in it until you reach the stripe!

Due to some local and division politics and a few other issues, we're running 1/8 mile this season in the NHRA Summit Bracket points series. So, I don't have to worry about the shift light being on in my new tube-chassis car this season. However, we have a perfectly good 1/4 mile track that hosts a Div-4 Lucas Oil event.

If I recall correctly, I believe you wrecked your car about two years ago. I hope you've got everything back together and are back at the track racing again.

WD
I rolled my car about a year and a half ago - 2nd points race in 08. It's not back together yet but I'm crossing my fingers for next season. As little as the damage was for a 130mph rollover, it's still a TON of work. Last year we didn't rush to get to it because my season was over anyway. And this year, things came up with family and it hasn't really been important. Right now, I wish I had the car for an outlet!! Last week I traded in my 6 speed Honda Accord for an Automatic Malibu and I will be out running in the street class a few times before this year is over. I can't wait!

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Old 08-07-2009, 08:48 AM
  #33  
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Originally Posted by 5SPDCHK
I rolled my car about a year and a half ago - 2nd points race in 08. It's not back together yet but I'm crossing my fingers for next season. As little as the damage was for a 130mph rollover, it's still a TON of work. Last year we didn't rush to get to it because my season was over anyway. And this year, things came up with family and it hasn't really been important. Right now, I wish I had the car for an outlet!! Last week I traded in my 6 speed Honda Accord for an Automatic Malibu and I will be out running in the street class a few times before this year is over. I can't wait!

Sorry to hear your car is not back together just yet, I know you really miss the racing (I know I would).

I've been in-and-out of drag racing several times over the years due to career, family, Etc. However, I've always really enjoyed drag racing, as-well-as the race car projects and building my own cars (as-much-as possible). Now that my kids are grown and I'm well established in my career, I've been racing really intense for the past several years and haveing a lot of fun doing it.

This season I took my racing to a new level with a new tube-chassis, Glasstek body Cavalier (SBC powered w/ P/G). While the Cavalier has a full electronis package (delay box, trans-brake, Etc.), I've been racing it in the No-E class this season and already have the points secured to run in the Div-4 bracket finals.

Here is a photo of the new car.

WD


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Old 08-07-2009, 12:28 PM
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Very nice! Good luck at the bracket finals!!! Maybe you'll be out in California in November!!!!

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Old 08-09-2009, 09:46 AM
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Originally Posted by 5SPDCHK
Very nice! Good luck at the bracket finals!!! Maybe you'll be out in California in November!!!!

I would love to be at Pomona to run in the NHRA 2009 finals! I've had my ups and downs with bracket racing and paid a lot of dues over the years (been beat-up really bad at times), however, I've stayed with it and last night I really had my act togehter! First round I drew the No-E points leader and took him out with a .018 light and ran dead-on my number. He bought back in and I drew him again 3rd round and took him out again.

I made it down to five cars and went red (ouch)! But I raced really well and my new car was spot-on and delivered the numbers every round. What doesn't come easy in life, you appreciate a lot more when you finally achieve some success.

Also, my new tube-chassis big-tire (32" x 14") car is "much more" competitive bracket racing than my LTX Camaro (a lot faster also).

WD
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Old 08-09-2009, 09:55 AM
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Well with a 3.89 gear and 28" slicks I go thru the traps about 7100 rpm's at 151.6. So since I shift at 75-7800 that means I have my gear then needed.
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Old 08-09-2009, 12:22 PM
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Originally Posted by jakesz28
Well with a 3.89 gear and 28" slicks I go thru the traps about 7100 rpm's at 151.6. So since I shift at 75-7800 that means I have my gear then needed.
Mike,

It sounds like you need some 4.30s possibly and maybe taller 29" slicks? Also, it was nice meeting and getting to visit with you at the Shoot-Out this year. Additionally, meeting your family!

Warren

Last edited by The Engineer; 08-09-2009 at 12:24 PM.
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Old 08-09-2009, 02:00 PM
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Yeah I was thinking the same thing. I went with the 3.89 just incase the converter was to loose and had to much slip. Now this converter is to tight and needs loosened. It has slowed down the 60'. I have to leave on both kits to get a 1.34 60' and the converter last year I was going 1.31 on about 180 shot. Last year I had about 12-14% slip this new ptc is about 5-6%. I opened the quarters for a 29" tire and left the 28's on there. I was thinking I needed something a little better then a 4.10 and a 4.30 is just borderline on the 28's. But a 29 inch tire could help in a couple ways.
I'm rethinking the whole combo right now. I have some noise in the bottom end and I need to pull it out but I would hate to keep spending what I have on a small motor then push it this hard. I could have bought a 632 short block for the money I put in this shortblock last year. I would like to step up the power a little more with some 12 or 18* heads but the block may not hold it all year and with a bigger motor I won't have to push it as hard.


It was nice meeting you too.
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Old 08-09-2009, 02:53 PM
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Originally Posted by jakesz28
Yeah I was thinking the same thing. I went with the 3.89 just incase the converter was to loose and had to much slip. Now this converter is to tight and needs loosened. It has slowed down the 60'. I have to leave on both kits to get a 1.34 60' and the converter last year I was going 1.31 on about 180 shot. Last year I had about 12-14% slip this new ptc is about 5-6%. I opened the quarters for a 29" tire and left the 28's on there. I was thinking I needed something a little better then a 4.10 and a 4.30 is just borderline on the 28's. But a 29 inch tire could help in a couple ways.
I'm rethinking the whole combo right now. I have some noise in the bottom end and I need to pull it out but I would hate to keep spending what I have on a small motor then push it this hard. I could have bought a 632 short block for the money I put in this shortblock last year. I would like to step up the power a little more with some 12 or 18* heads but the block may not hold it all year and with a bigger motor I won't have to push it as hard.


It was nice meeting you too.
Mike

I had to slightly trim my quarters down at the rocker to get my 29" x 10.50s to clear. However, the 29" slicks were an improvement over the small 28s on my car (i.e., 1.48 60fts now). With the HP you're making and the ETs you're running, the 29" should be much better.

Also, what is the latest on the new LTX Dart block with 4.125 bore? I believe with .030 over bore and 4.00" stroke, that would be a 434 CI LTX engine. Wow, I love it! There's no replacement for displacement!

Warren
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Old 08-09-2009, 03:05 PM
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Engineer, sweet looking bracket car, and nice job beating the points leader 2 races in a row. That's got to help get into his head for the next time you line up against him.
I believe I read the LTX block was put on hold for now.
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Old 08-09-2009, 03:30 PM
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Originally Posted by The Engineer
Mike

I had to slightly trim my quarters down at the rocker to get my 29" x 10.50s to clear. However, the 29" slicks were an improvement over the small 28s on my car (i.e., 1.48 60fts now). With the HP you're making and the ETs you're running, the 29" should be much better.

Also, what is the latest on the new LTX Dart block with 4.125 bore? I believe with .030 over bore and 4.00" stroke, that would be a 434 CI LTX engine. Wow, I love it! There's no replacement for displacement!

Warren

I have to agry with you on the 29" tires that might help me a little when I get it back out and some adjustments to the IC, shock ect.

As far as the dart block I couldn't wait on something that they might make and then they might not. Until it is availble I'm not even looking at that as an option. I was told about some bowtie LT1 blocks and I should check back on them but then I could buy an BBC aftermarket block for less. So that is what I keep going back and forth on. I would love to stick with the block I got but with more power it will always be the weak link. If I do go to a different sbc block or the bowtie LT1 block I think I would stick with the 3.75 stroke to help keep a nitrous friendly ring pack on it.
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Old 08-09-2009, 05:27 PM
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Originally Posted by jakesz28
I have to agry with you on the 29" tires that might help me a little when I get it back out and some adjustments to the IC, shock ect.

As far as the dart block I couldn't wait on something that they might make and then they might not. Until it is availble I'm not even looking at that as an option. I was told about some bowtie LT1 blocks and I should check back on them but then I could buy an BBC aftermarket block for less. So that is what I keep going back and forth on. I would love to stick with the block I got but with more power it will always be the weak link. If I do go to a different sbc block or the bowtie LT1 block I think I would stick with the 3.75 stroke to help keep a nitrous friendly ring pack on it.
Mike,

So, you're thinking BBC and wanting to go fast! You may end-up like me, with a LTX car and a completely different "go fast car" without "any" LTX parts.

I love my LTX car and really enjoyed all the years I spent learning "every detail" about the LTX game (PCM/EFI, Opti, reverse-coolant flow, 4L60E, Torque-Arm, Etc.). But when I strap-in and go down the track in my 2140 lb tube-chassis car (SBC 400+ ci w/ P/G), I'm not even thinking LTX issues.

I'm working on a new SBC stroker engine (Dart block) for the car that should put me down into the 8s for next season.

Warren
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Old 08-10-2009, 06:57 AM
  #43  
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The way to do this is as follows (if the goal is to optimize for the 1/4 mile):

1. estimate your trap speed
2. estimate peak power rpm
3. pick a gear and tire size that will put you a couple hundred rpm past peak hp through the traps

Rich
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Old 08-12-2009, 09:01 AM
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This is how i normally get my gear ratio as close as possible w/o having to change gears. I run my car both on motor and n2o so i just swap from 26" tires for more gear on themotor and put 28" tires for n2o runs. Later
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Old 08-12-2009, 05:43 PM
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Originally Posted by T/A lt1
This is how i normally get my gear ratio as close as possible w/o having to change gears. I run my car both on motor and n2o so i just swap from 26" tires for more gear on themotor and put 28" tires for n2o runs. Later
With the tight conveter, 3.89 gears and a 28" tire I like it when someone that doesn't know my car sees me make a motor pass. They mention something about how slow it is and lazy off the line.


Then the next pass all hell breaks loose.
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