Dogtracking?

[davet]

I've searched for these answers but didn't come up with anything for intentionally dogtracking.

With a railrunner are the rear wheels experiencing sliding friction on the track surface because they're not running parallel to the track? Our DFW is the left front. Would it be advantageous to run the left rear with slight toe out and the right rear with slight toe in so they both run parallel down the track surface? If there's a thread that covers this just point me in that direction instead of rehashing it here. I just didn't find it.

 

[GravityX]

Any toe in the rear will scrub off speed. Not recommended. Cant only- no toe.

 

[Obsessedderbydad]

I think with proper alignment and proper staging you can have the car run down the track with the rears off the rail and the car parallel.

 

[ngyoung]

I think what he is asking is since the DFW is against the rail and the back wheels are spaced evenly from the rail the car body is slightly angled. The only thing I can think that keeps the back from wanting to roll into the rail too is the slop between the axle and bore allows the wheel to stay parallel.

 

[davet]

I think what he is asking is since the DFW is against the rail and the back wheels are spaced evenly from the rail the car body is slightly angled. The only thing I can think that keeps the back from wanting to roll into the rail too is the slop between the axle and bore allows the wheel to stay parallel.

That's what I was thinking. I didn't consider wheel/axle slop but that still wouldn't point them straight down the track.

 

[5KidsRacing]

If on purpose you drilled your rears so they were not perpendicular (but at an angle) to the length of the body, you would make a car similar to a perfect drilled car with a DFW cutback.

Or in other words..... if you took a bearing car with a solid rear axle and you angled the rear axle 1 degree, you would change the rear wheel position with respect to the rail.... done correctly you could create the same thing as you would do by cutting back the DFW.... you can center the rears without the cutback.

The rear wheels would run straight down the track, but the body would just be at a slight angle. It is easy to do, just narrow your body a little and twist it slightly when clamping it into the Silver Bullet. You want about 1 degree of "dogtrack" to get the right DFW setback.... would be around .080-.100" for a 5-1/4" WB car.

 

[5KidsRacing]

I've searched for these answers but didn't come up with anything for intentionally dogtracking.

With a railrunner are the rear wheels experiencing sliding friction on the track surface because they're not running parallel to the track? Our DFW is the left front. Would it be advantageous to run the left rear with slight toe out and the right rear with slight toe in so they both run parallel down the track surface? If there's a thread that covers this just point me in that direction instead of rehashing it here. I just didn't find it.

so... no you wouldn't want to do that.... you want to drill you rears exactly the same across from each other..... just at an angle to the body.

 

[davet]

The rear wheels would run straight down the track, but the body would just be at a slight angle. It is easy to do, just narrow your body a little and twist it slightly when clamping it into the Silver Bullet. You want about 1 degree of "dogtrack" to get the right DFW setback.... would be around .080-.100" for a 5-1/4" WB car.

Wouldn't this be ideal. Car would run at angle to track just like a railrunner but rears would be straight down the track with no sliding friction? Or, would this cause the rear to steer into the rail also?

 

[Kinser Racing]

If you keep your axles at a centerline drilled perpendicular to the body, you won't dogtrack. The car will center it's self. This is why you stage a car a certain way. It's also why some cars will have one rear wheel closer to the track than the other, which also has to do with the inset of the DFW.

 

[GravityX]

In the automotive world of car alignment this would be referred to Thrust Angle as seen in the image below... Is this what you are talking about Scott? Instead of 1 degree I was thinking 1/2" degree or less.

 

[ngyoung]

I think he was asking about correcting the rear wheel path assuming the car looked like this:



The angles are exaggerated but I think it represents what he is asking about with dogtracking.

In the automotive world of car alignment this would be referred to Thrust Angle as seen in the image below... Is this what you are talking about Scott? Instead of 1 degree I was thinking 1/2" degree or less.

 

[5KidsRacing]

I think he was asking about correcting the rear wheel path assuming the car looked like this:



The angles are exaggerated but I think it represents what he is asking about with dogtracking.

Exactly.... You rears will run straight down the track like is shown in the second picture and you will still adjust the DFW for the right amount on drift.... you body will just look a little crooked. Still a perfect drilled car... Now if you put it at too much of an angle it will shove your wheels so far one way and your DFW so far the other that the car will not fit on the track.

Is this a good method for eliminating the DFW setback? No, not in my opinion.... Too hard and you don't need to setback the DFW anyway if you use the methods we use here...

 

[davet]

Exactly what I was picturing. The top pic is what we have with a railrunner now. The second pic would still be a railrunner with inset DFW but the rears would be slightly turned to keep wheels running perfectly straight. Seems you could run slightly less drift too. I'm too new to this to really say one way or the other and don't have a track to test on. Maybe I don't understand the explanations as to why this is bad.

5KR-- How do you make a railrunner without DFW setback as u mentioned above? Wider rear gap?

 

[5KidsRacing]

With negative canted rears and a positive canted DFW your rears should not hit the rail and you don't need to cut back the DFW.... Don't widen the gap on the rears, you will lose speed...

 

[davet]

Thanks. Is there an advantage to that other than just not having to narrow the front?

 

[5KidsRacing]

No, not that I know of.... the advantage of cutting back the DFW is so the body is more aligned with the center rail so staging is more foolproof.

 

[davet]

Got it. Thanks.