Competition ET vs. MPH

[BigUgly]

Jeff's MPH

HVAC;

Jeff ran 112 mph.

Josiah

 

[HVAC]

Jeff's Truck

It may be necessary to delete Jeff's truck from Stack's observation. His truck is stripped and much lighter then the rest of us. I thought someone said the white truck runs about four thousand and change.



I think this demonstrates the effect of weight vs top speed with regard to ET. A light rig (or a mustang/camaro) can run a quicker time at 112 mph then my truck for instance. My truck weighs about 5800 pounds by comparison. A heavier truck like "Jet's" runs 118 mph and still can't break into the elevens! He's going to be slower getting the load rolling as a result of the much greater weight.



This is one of the things that is slighly humorous about racing these trucks against mustangs etc. We can beat them while weighing thousands of pounds more then they do

 

[DHRA]

I thought that Jeff's truck was around 112, thanks Josiah.

This is inline with what I am saying Mr. air conditioning man. You run a second slower at the same speed. So many variables, but my next question is: can it be the increased air flow? Could it be cam design? Could it be a limitation in the fueling? I am still working on proper air flow vs. air temperatures. Next will be cam/piston/rocker arm/valve experiments.

Each increment from the mid 12's to the low 12's is going to take some serious answers if I want to see the low 12's on diesel only.

 

[FFutch]

All I can say is...

... you guys impress the h#ll out of me. 12 second quarter and you want more out of a 7k truck. You're already faster than my 440-6 charger and almost twice the weight. Eric what's the fastest you ran with a 5 speed,and how much h. p. ?What was your shifting technique?I'm just wanting to get a little faster than 15. 9 without having to go to an auto and without smoking the clutch too bad... Doug

 

[DHRA]

My average with the five speed was 13. 8 I ran a 13. 5 once. Dynoed at the end of last year 613 hp. The problem I encountered, since you mentioned the clutch issue, was once Van Haisley built me a clutch worthy the task, I went through transmission parts. That is why I switched to an automatic.



My shifting technique was to launch in second gear 4wd then go to 3rd, switch to 2wd, then 4th. Some tracks I used 5th, some I didn't. I could run 4th grear over 100 mph.

 

[FFutch]

Thanks Eric. It looks like the first thing I need to do is some more bombing . I'm only at 400 h. p. now. I guess that credit card will never get paid off ... Doug

 

[mopars1]

Just to inject a little Drag Racing thoughts that I have learned over the many years of racing, even though I can't say how they affect the heavier turbocharged vehicles we drive (as I have never raced the truck, one wheel drive impaired) is this; if the vehicle cannot get hooked to the track very well, the ET suffers but the MPH goes up because the wheel speed got a "head start" so to speak. The opposite is true for a vehicle that gets lots of traction and does not "bog" off the line will run a better ET and a lower MPH. Take for instance my race car, if the slicks and track are there I generally get a 1. 34 second sixty foot and run in the area of 10. 06 to 10. 13 given the varying conditions. If the track isn't there I will get up to 1. 45 sixty foot times and run around a 10. 25 or so. My MPH doesn't change that drastically but will change in the area of 2-3 MPH. As I stated, some of this does apply to our trucks, but there also is a lot more that goes along with it. For instance, if I was running a big block and ran the same times, my MPH would be 4-6 MPH higher because of the larger cubic inches and moving more air through the engine.

I always look at the ET as Torque coming off the line and MPH as Horsepower in the higher rpm's.



David