MPH vs. ET

[stu]

So so far, my best time in my car has been a 17.0x at 79.xx miles an hour on a slipping clutch. I've since changed plugs, wires, cap and rotor, and fuel filter. At club clash the other day, the clutch dicided to basically kick the bucket so I was running 17.311 and 17.446 at 81.50 and 81.40mph respectively. Now I just started drag racing this year, and was wondering what the connection between MPH and ET is; is two mph a significant improvement? I thought I heard somewhere that every 10whp gets you so many mph or whatever. Do any of you guys have some sort of basic equation that you go by? Basically, I've been telling people that I think I will break into the sixteens with just a new clutch based off of my previous best of 17.0x @ 70mph. Now, in a couple of days I will be getting a much stronger clutch and a 12lb flywheel, so I think that consistent 16's shouldn't be a problem. Anyone disagree? Agree?

The only thing I can think of that would be a problem would be the lighter flywheel for the launches, but I had an 8.5lb one in my GSR and never had a problem launching.

[john]

I lightweight flywheel will more likely give you worse 60' times.

ET is representative of the driver, whereas MPH is more about how much power the car is putting down.

There isn't really any standard math or formula you can use to correlate ET to MPH to ??, since every car is different, as are all drivers.

[stu]

I figured as much, thanks John. :)
Hey, why don't you come to club clash?

[WRX Harvey]

I think with a higher trap speed, and a new clutch, 16s won't be an issue for you. IMHO.

[theskeptic]

There are standard formulas for figuring horsepower based on vehicle weight, using your trap speed and E.T.'s. Try this link out:

http://home.attbi.com/~omniphil/acr/hpcalc.htm

Punch in the weight of your car (with you in it, of course) and your numbers from the track and see what you get.

Generally speaking, unless you're running slicks, you'll use the HP number produced by the trap speed method. Since my car is AWD the numbners can be skewed.

My WRX weighs about 3300 pounds with me in it at the track. I ran a 14.17@95.117 so the estimator says:
Using MPH: 221.63 HP
Using ET: 228.99

For arguments sake, let's say your Integra(?) weighs 2850 with driver at the track. With a 17.3@81.5 your numbers are:
Using MPH: 118.29
Using ET: 106.88

With a better launch and a new clutch you could hit 83-84 mph if you keep practicing at the track. I found with my FWD Omnig GLH Turbo that I would get massive wheel hop with radials.

I found that by lowering the pressures in the front to 15 psi would let them spin without hopping. I went from 2.4 sec 60 fts to consistent 2.2's. My ET's dropped by over 1/2 second at the same time!

A NOS setup wouldn't hurt yah, either!

-Dana in Santa Fe