ET vs MPH

[hensleyt]

got my ETs down to 11.847 but my MPH got slower 113.03.Been working on my 60ft .Best MPH 114.11 @11.921 60ft 1.802 660ft 7.651@92.05. Best ET 11.847 @113.03 mph 60ft 1.741 660ft 7.537 @91.13. they look close to me but a local racer felt my MPH should have went up not down,What do you think?Changes to fix 60ft were air pressure and 2-step.

 

[Slow91z]

Typically when a car spins the mph goes up, not that you made it hook it should drop a bit.

 

[bison]

Like already mentioned mph could drop a little with a lot of spin. Typically heat soak will limit mph without a lot of cool down also.

 

[hensleyt]

My 60 got better this weekend .and the car had to idle more,water temp was up from 160 with my best mph two week ago to 165 this weekend .was going to research a way to turn the fan on sooner in staging lane.drag calculator shows a 11 hp lose.I made more passes two weeks ago but water temp stayed 160.I have 1qt of antifreeze in the system, should I add my Purple Ice?

 

[Blazer406]

IMHO... some wheel spin.... MPH is usually higher than compared under the same conditions otherwise... except no wheelspin.

MPH is the better indicator of HP, but it is best to compare hooked.... to hooked..... HP is also greatly affected by track (air) temp and humidity as well...

 

[87chrisss]

how much boost are you launching with? what rear setup do you have in terms of sway bar and arms? got bags?

 

[hensleyt]

I leave of the 2-step at 2800,I have made 6 passes and I forget to look every time.Hellwig bar,28X9 Hoosier and UMI bars.My best MPH was a test and tune day no waiting in line.never thought about heat soak