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I want to know the same! wanna know if its even worth me doing the 1/4 mile when my car is done.
 

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Seat time is seat time. Do it regardless of if it's slow or not. It's why you built the car right?!
I will be mostly street driving my car and roll racing at the Poconos event. Not willing to destroy my stock rear and clutch for a shit pass at the 1/4 mile unless its worth a good pass.
 

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Discussion Starter #5
If you have 6 puck or twin disc your clutch should be fine I made some pass at 600whp on act 6 puck sprung. My diff on the other hand didn't do so well the mk3 supra diff is suppose to be able to hold 800whp or so but mine didnt. I rebuilt it with yukon gears gonna make passes later this year see how it goes.

It's definitely a lot of fun you should go even if you come off the line soft
 

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I'd love to know what mine does but probably never make it to the track. :lol:

Once I get it to hook up I'll be more enticed.
 

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Discussion Starter #10
im gonna have a stock LSD rear with over 900 thing cant wait to explode lol
Just launch easy 10psi or less is what most people seem to launch at but with drag racing anything can happen.. my i destroyed my rear end last year without 2step but on drag radials
 

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Just launch easy 10psi or less is what most people seem to launch at but with drag racing anything can happen.. my i destroyed my rear end last year without 2step but on drag radials
Yea that's gonna have to be the move
 

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I plan to take mine down, but nearest track is 3 hour drive one way. I will likely play around with launches on the mr dyno/gtech on the street to sort out a few issues before I go. Either way, I think it's worthwhile to go through the motions to figure out how to launch your car and get moving quick. On the street, I really don't think it's fun to do 180mph, and would rather get it over with quick. The more you can maximize what you have, the better the odds that you can have the race over and done with by the time you reach the speed limit.

I modified the typical ET/MPH from hp formulas when I had my Aristo to get more reasonable prediction for mediocore street tire/suspnsion for trying to hit a number at the track. It was a good guideline for me to figure out what side of the line I was on and where I should improve. i.e. If a person is running in low 11 second range with only 120mph, you know its a drag tire setup, and something very very good is going on to get it to hook that well. If someone is running 140mph and only high 10s, you know they are making a crap ton of power and there is definite room for improvement on the traction side.

There are too many variables to make it perfect, but some comments - power curve plays a big part in your overall times/speed. If you only make 460whp peak for 500 rpms, don't use it to predict your times. If the average is more like 420whp, use the average 420whp number.

Also dynojets might get slagged for producing bigger numbers, but it's a really a super simple device and error is more likely on the operator side. Post the corrected numbers to compare to other cars power numbers from around the globe, but ask for uncorrected numbers if you want to figure out how fast your car is going to go.

Drag tires/and really drag focused suspensions should be able to improve over these times.




 

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Discussion Starter #13
I plan to take mine down, but nearest track is 3 hour drive one way. I will likely play around with launches on the mr dyno/gtech on the street to sort out a few issues before I go. Either way, I think it's worthwhile to go through the motions to figure out how to launch your car and get moving quick. On the street, I really don't think it's fun to do 180mph, and would rather get it over with quick. The more you can maximize what you have, the better the odds that you can have the race over and done with by the time you reach the speed limit.

I modified the typical ET/MPH from hp formulas when I had my Aristo to get more reasonable prediction for mediocore street tire/suspnsion for trying to hit a number at the track. It was a good guideline for me to figure out what side of the line I was on and where I should improve. i.e. If a person is running in low 11 second range with only 120mph, you know its a drag tire setup, and something very very good is going on to get it to hook that well. If someone is running 140mph and only high 10s, you know they are making a crap ton of power and there is definite room for improvement on the traction side.

There are too many variables to make it perfect, but some comments - power curve plays a big part in your overall times/speed. If you only make 460whp peak for 500 rpms, don't use it to predict your times. If the average is more like 420whp, use the average 420whp number.

Also dynojets might get slagged for producing bigger numbers, but it's a really a super simple device and error is more likely on the operator side. Post the corrected numbers to compare to other cars power numbers from around the globe, but ask for uncorrected numbers if you want to figure out how fast your car is going to go.

Drag tires/and really drag focused suspensions should be able to improve over these times.
Those are really cool graphs your right about the 1/4 miles its hard to estimate that because of the variables but the mph one looks pretty accurate! My car last year around 560whp went 126mph for comparison
 

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Ran mine last summer. it was the first time i ran it at the track in several years. Only running 13psi of boost on a 6765. Makes roughly 390whp on a mustang dyno at that level. Ran a 12.62et. I think that was at 114mph. Not that impressive but, it was my fastest pass yet. I hope to get this damn V160 in, and some larger injectors to make more power and see where it goes then.
 

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Ran mine last summer. it was the first time i ran it at the track in several years. Only running 13psi of boost on a 6765. Makes roughly 390whp on a mustang dyno at that level. Ran a 12.62et. I think that was at 114mph. Not that impressive but, it was my fastest pass yet. I hope to get this damn V160 in, and some larger injectors to make more power and see where it goes then.

That is a pretty decent run. What tires were you running and do you know what your 60 foot time was?
 

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Those are really cool graphs your right about the 1/4 miles its hard to estimate that because of the variables but the mph one looks pretty accurate! My car last year around 560whp went 126mph for comparison
Thanks, like I say, I tweaked something a few years ago until it started to make sense for more typical street setup and most of us that won't get a killer launch.

Out of curiosity, after that, I went through a few pages on the 1/4mile sticky and found quite a few examples that were close as far as ET and MPH.

A couple things I noticed after reading some times on there... we all need to look to Parish8 for slick advice/launch tips. low ET given the MPH for an IS (V8 guys do have some good secrets). That and Yojimbo is an anomaly on the hp curve ( squeaking out a few more ponies on track day than dyno day I suspect... awesome mph)

The base data for the chart might be an easier format to read - see below if anyones interested

 

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That is a pretty decent run. What tires were you running and do you know what your 60 foot time was?
I was running some worn out M/T ET streets on Rx7 rims. 255/50/16.

Keep in mind I use NO launch control or antilag off the line. My car isn't set up for it yet.

I don't know my 60' time off hand. I'll have to look for my time slip. Here's the youtube vid though.

https://www.youtube.com/watch?v=uIkDUr41EnE
 

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So I took a few runs at Pittsburgh Raceway Park now known as Keystone Raceway Park in New Alexandria, PA Last Saturday night. This was the first I've had my car to the track this summer. Still on the same setup as last year:

M/T ET streets on Rx7 wheel 255/50/16's that are pretty worn. Boost controller was set at 13psi and peaked at 17psi. Again I don't use antilag or launch control off the line.

My first pass of the night I ran a 12.51 at 115 mph.
My last pass of the night I ran a 12.33 at 115 mph. I'll post my slips when I get home from work. I didn't lose these ones like i did before.

12.33 Is now my personal best. I believe my 60' was a 1.8
 
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