Axle hole heights

[CDB Racing]

I have been testing with different axle hole heights and just wondering what the most of you are doing. I am drilling the rears 5/32" high, 5/8" from the back end. I am currently using a 5" wheel base, but built a car with four different wheel base lengths starting at 5" - 6/32" high and moving back and 1/8" and down 1/32" for four holes. I was surprised at which was faster. I know there are a lot of variables at play and could have been the mount of drift I had for the fastest run. I have read 3/32", but can't help but think that makes the front of the car to high. My son is a Bear and this is our third year in cub scouts. I have also sent a couple of cars to race, but was 35 out of 40. That was a graphite car against mostly oil cars. I have not perfected the oil yet.

 

[DNA RACING]

i do things somewhat against the grain with reguards to axle hole height. i try to drill the rears at a 1/16" from the bottom. and the fronts about a 1/8" up from the bottom, this lowers the front end a bit, i believe this allowes less air under the car and what air does get under flows freely out the back as the rear is higher. when i get them drilled, i sand the top to a wedge, getting as close to the front axle hole as i dare. then i sand the bottom flat as close to the holes as i can.

 

[CDB Racing]

What does that do for the toe out on the rears? Assuming you cant your rear wheels. The 6/32" front hole produced the fastest time on that particular car.

 

[DNA RACING]

no idea, never thought about it before.

 

[E.T.Racing]

My thoughts are that once the holes are drilled how you cut the body shouldn't matter, the hole relationship should not change, just my $0.02.

 

[W racing]

In my book you want the car level or the nose a tad higher. However with the bent axle that takes some experiment to hit the sweet spot.

 

[DNA RACING]

wouldnt the nose higher act as a air scoop ? more air in less air out causes a high pressure area under the front end?

 

[ZZ Racing]

I always run with the nose slightly higher or level. If I run with the nose lower I can't get the speed out of it like the other ways.

 

[W racing]

For folks that are good with the silver bullet. Like yourself. Level works great. It is easy to do but you need to build a few cars to get the hole height correct.

For folks just starting the nose up aproach gives them a little more lee way.

If you lift a car up you will notice toe-out on canted rears. Push it down you have toe-in... Level no problem as long as holes are drilled well...

 

[CDB Racing]

It also depends on the amount of bend in the front axle and the wheel base. Thanks, I have some practice drilling holes and testing to do.