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Discussion Starter · #1 ·
What is the biggest determining factor for high MPH in the 1/4 mile? I've seen some with the same power as myself, running 118, 119 and 120+, getting the same 60's (2.0-2.2) but are getting in the low 12's at these insane speeds. I ran a personal best last night(slow for you experienced guys) but my best none the less. Time below:

2.122 60'
8.319 1/8
90.74mph 1/8
12.64 1/4
114.8 1/4

Obviously the 60' needs alot of work. But I cant do a proper burnout, without some more training/practicing because thats how I lost my last clutch. So all I can do is heat them up, which is why my time gets better as the night goes on. But as far as speed goes, I'm well into 4th gear when I cross the traps. Any ideas??
 

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It's very difficult to find the rhyme or reason to MPH at the track. I have found that quick ETs and MPH can tend to be opposing factors.

For examle, my best MPH's come when I spin out of the hole and get a crappy ET. JT put it best to me once: "The quicker you get down the track, the less time your car has to climb with speed" This has held true when all things are equal...meaning no mods to the car.

But, of course, if we add 100 HP to the car both ET and MPH will improve.

As far as your times, 03Snake, you must take into consideration ALL of the factors that produce quick ET's and high MPH. All of these things togather constitute what we call a "clean pass" down the track.

IMO, the factors that make up a clean pass are:

1. Sufficient cool-down - We all know that these cars are animals when cold. If you have friends at the track, have them help you push your car right up to the waterbox after a long cool-down.

2. Good burnout - JT taught me his 2nd gear burnout technique and it helps a lot! Here, line locks prove invaluable. The idea is to smolder the tires and get them very sticky without heat-soaking the blower. To do this, you must warm up the tires without reving the motor or going into boost. This is possible with a 2nd gear burnout and is easy with the tires wet from the waterbox.

3. Good launch - not bogging and not overly spinning. The goal is to keep the RPMs consistent from the stage to the forward momentum.

4. Good shifting - we all know that best passes happen when flat-shifting the car and keeping recovery time to a minimum.

5. Nailing your shift points - I think that this is one of the most under estimated factors in racing. Both over-reving and short-shifting KILL ET and MPH. Finding your car's best shift point can usually be ascertained from a dyno sheet and then practice at the track.

For example, I try to granny-shift the 1/2 at 5000 RPMs and then flat-shift the 2/3 and 3/4 at 6200 RPMs. I short-shift the 1/2 because the high torque and HP that my car makes above 5000 RPMs causes the tires to spin until the car has enough forward momentum (meaning 70 MPH or better). And I aim for 6200 RPMs down the track so as to broaden the powerband as much as possible without over-reving, heat-soaking and thermally breaking down the machine during the run. Also, my HP starts to drop beyond that point.

For any car, the optimal formula depends on the specific mods, weight, power and traction for that vehicle. It takes practice!

Here's another good but widely unknown tip for you: What's the single HEAVIEST and movable component in your car? YOU!! You will obtain your best performance if you can get your own butt to the back side of the weight distribution of your car. In other words, practice driving with the seat AS FAR BACK AS YOU CAN GET IT...while still reaching the pedals. It takes getting used to for a while. An old-school racing secret is to extend the pedals or put blocks on them! I have found that the biggest obstruction to this technique is clutch operation. If you're back too far to fully activate the clutch then you will start missing shifts. This is where an adjustable firewall and quadrant come into play. You can set up your clutch pedal so that it fully activates with 2 inches of movement from the top.

That's everything I know, man. Full disclosure. Hope it helps.

:salute

Edit: typo's
 

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Discussion Starter · #3 ·
Thanks Rich. Lots of this I hadn't given any thought to. Pratice!!!
 

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That's about the best description I've seen. Excellent!
 
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