What is the general rule when drag racing. I thought usually if you got a lot of wheel spin to begin with you tended to trap a little higher then you might if you just hooked and booked? So you may run a slower time but have a higher trap speed, but as you mangage to get the car to hook up properly the trap speed may decrease a little.

Can anyone shed any light on this?

Tried searching.

 

Hmmm

 

Hook up= Lower ET and Lower MPH
Spin= Higher ET and Higher MPH

The better I hook the lower my ET goes and lower my MPH goes.

 

Hook up= Lower ET and Lower MPH I agree with this.
Spin= Higher ET and Higher MPH I think this can vary.

 

i agree with above

 

Cheers guys any more input? Anyone know why this happens?

 

My theory is that the car has more time to accellerate, resulting in a higher trap. But every time I think about it I have conflicting ideas. I'm also interested in what the pros think.

 

I once heard from a pro race car driver that some(not alot) of spin is good.

Im not sure if this is true but think about it....
A car with some spin is still going to hook while gaining momentum while a car that does not spin has to pick up the momentum on the go....idk

 

you're going to get SOME wheel spin in most cases. I guess you can totally take out the wheel spin factor if you have enough weight on the front and hook on the tire, but thats alot of stress on the drivetrain.

I say some wheel spin is ok for most people. its a give and take for the sake of saving parts.

 

in some cases while your spinning tires you are building up inertial energy (stored HP) which helps "sling shot" you after hooking up. this is why you may see the same mph with a good launch or a poor one.

with everything being equal from shifting to head wind. if you put maximum power to the track you will achieve maximum mph.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by trickeng &raquo;</TD></TR><TR><TD CLASS="quote">in some cases while your spinning tires you are building up inertial energy (stored HP) which helps "sling shot" you after hooking up. this is why you may see the same mph with a good launch or a poor one.

</TD></TR></TABLE> Yeah this theory makes sense. Thanks

 

I feel as though, like stated above that a small amount of wheel spin is necessary in a fwd car in order to get momentum.

I do think that wheelspin effects mph but not a whole lot, i've noticed when i bog my mph is slightly lower than if i spin. thats just my experience.

on a RWD car with good weight transfer and suspension setup i think that you dont really want any wheelspin at all in order to make a good run, if you've got the right tire, and suspension setup along with the launch you shouldnt have any wheelspin on a rwd car. but thats just what i think and my experience from the last 3 going on 4 years of driving a 9 second camaro.

 

when you hook up you are further down the track so you have less distance to get the mph. my opinion

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by maxwell sohc &raquo;</TD></TR><TR><TD CLASS="quote">when you hook up you are further down the track so you have less distance to get the mph. my opinion</TD></TR></TABLE>

ya.

 

I can probably get a scientific answer for you guys, I would guess that it has to do with storing energy in the tires when they spin making your total work done be greater, do to you having a longer time to get down the track.
When you fall out of static friction and into friction between sliding surfaces you are going to experience a loss in energy, but if you consider that when doing a burnout and you let off the gas, the car still pulls while the driveline slows down, which would make it seem that energy is stored in the rotational mass.

Since work is a funtion of force over a distance, in the 1/4 mile the distance doesn't change so the only possibility is that the force is increased. If a car does a pass under ideal conditions (perfect launch, perfect shift, etc), it would be reasonable to assume that the trap speed would be related directly to the output of the engine.
now if we consider adding wheel spin out of the hole into this scenerio, there is now a longer time to travel the track (hence higher ET), since the engine is still outputing the same amount of force to the wheels but has that slightly longer time, the difference in trap speed appears to be related to the amount of energy that can be stored in the rotating mass, after deducting the losses of course.

This is just a quick thaught that im dreaming up lol.. Ill run it by a couple of my professors and get back to you guys on it.

 

Maxwell, your guys car is sick. I drive the silver ef hatch with the checkered flag on it that has had nothing but problems. We went with the axlesystems like you sugested.

Do you guys have anything instore for this summer? Or is it too good to change?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by exospeedAMcrx &raquo;</TD></TR><TR><TD CLASS="quote">I say some wheel spin is ok for most people. its a give and take for the sake of saving parts. </TD></TR></TABLE>

Ditto.

I typically run the same MPH whether I spin a little or grip the entire time. I can't remember spinning 'ALOT'. Well... I did a whole 2nd gear burnout down the track... but can't remember the MPH on that run (1/8th mile).

I am nearly the same trap between street tires and slicks as well.

 

up for more info. Obviously a few people are afraid to stick there heads out??????? Wheres the drag racers..


Modified by turbozxi at 11:58 PM 3/1/2007

 

are you saying i'm not a real drag racer??? thats not very nice, since i gave you answer.

your mean!!!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by trickeng &raquo;</TD></TR><TR><TD CLASS="quote">are you saying i'm not a real drag racer??? thats not very nice, since i gave you answer.

your mean!!!</TD></TR></TABLE>Haha no no not at all.

I am getting a different story on another forum, just looking to try and get a definite answer. Perhaps its different with RWD cars? Most of these guys are saying they get better MPH if they hook up..

 

my answer stands true for FWD and RWD.

if you have the power and can keep your engine spooled up then full traction will yield higher mph and lower et. if it take a little wheel spin to keep your engine in its peak power than you may need the slippage. lot of variables.

but the fact is your trying to the most average hp to the track from the start line to the finish line. who evers total is higher wins the race. reaction time being equal of course.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by trickeng &raquo;</TD></TR><TR><TD CLASS="quote">my answer stands true for FWD and RWD.

if you have the power and can keep your engine spooled up then full traction will yield higher mph and lower et. if it take a little wheel spin to keep your engine in its peak power than you may need the slippage. lot of variables.

but the fact is your trying to the most average hp to the track from the start line to the finish line. who evers total is higher wins the race. reaction time being equal of course.
</TD></TR></TABLE> Thank you sir.

 

It can go several ways.. You can spin and have a high e.t. and high mph, and you can hook and have a lower e.t. and a lower mph..but thats not in every case..I have ran a lower E.T. and a higher mph for the fact there was no spin and all momentum created a higher trap speed..There's definitley a fine line line between spinning tremendously and slight spin..

 

I think I remember learning from a pro-stock team or driver or somewhere that you want around 12% slippage to produce the best et, mph doesn't really matter cause it doesn't win the race.

 

From my personal experience...

More traction = Quicker E.T.'s and Faster trap speeds.

Everytime I spin, it kills both.

- Derek