Finalizing my car - 3 questions for the PWD masters

[Vitamin K]

On top of this I had lathed my wheels, to be super light and trued, coned inner and outer hub.

I'm curious as to how you did your wheel modifications. It's a lot easier, IMO, to make a slower wheel than a fast one with DIY-mods.

[Loud2ns]

A couple of things.

I'm curious as well about the wheels. VK's spot on with the analysis on modified wheels. Way easier to make them slower by doing the wrong thing inadvertently.
The wheel sealant is a variable for me as well, as I've never used it. You may want to try a proven sealant to eliminate that variable. imo

The other thing is that you're racing on a 42-foot track, which would account for the slower times than the other ones you listed.

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[Hyperfocus]

On top of this I had lathed my wheels, to be super light and trued, coned inner and outer hub.

I'm curious as to how you did your wheel modifications. It's a lot easier, IMO, to make a slower wheel than a fast one with DIY-mods.

I sent a bunch of wheels to somebody locally who could lathe them. They came back in seemingly good condition, thinner tread, 1/3rd lighter. Now that I think about it, the wheel bore had some scratches which I had hoped weren't major and that polishing would amend, but perhaps not. Good thought on that.... I wonder if those scratches were the issue. I will take a picture tonight for us to look at. Cheers!

[Hyperfocus]

A couple of things.

I'm curious as well about the wheels. VK's spot on with the analysis on modified wheels. Way easier to make them slower by doing the wrong thing inadvertently.
The wheel sealant is a variable for me as well, as I've never used it. You may want to try a proven sealant to eliminate that variable. imo

The other thing is that you're racing on a 42-foot track, which would account for the slower times than the other ones you listed.

Sent from my SM-G991U using Tapatalk

Haha no doubt! I straight facepalmed when I read that. I didn't even notice, the Awana website lists the 35' track as the "one they use" but I did hear over the weekend that the two tracks were donated to the church 15 years ago, so this makes sense now. The tracks were in mediocre condition; they don't store them in boxes, just placed under the stage for the year. I set them up for the event, the section seams weren't perfect, and I had to wipe down both tracks and they were super dirty. I'm going to offer to do some maintenance on the tracks for the church, use simple green to clean, carefully de-burr some of the track edges as best as possible.

[exoray]

I'm going to offer to do some maintenance on the tracks for the church, use simple green to clean, carefully de-burr some of the track edges as best as possible.

I found that a 1:1 white vinegar/water mix wiped up and down the track while keeping it wet for a while as you wipe up and down works best for neglected aluminum, then I follow up and keep up with the Simple Green...

[Hyperfocus]

I'm going to offer to do some maintenance on the tracks for the church, use simple green to clean, carefully de-burr some of the track edges as best as possible.

I found that a 1:1 white vinegar/water mix wiped up and down the track while keeping it wet for a while as you wipe up and down works best for neglected aluminum, then I follow up and keep up with the Simple Green...

Good advice! I will do that, thanks

[FatSebastian]

Result from Saturday was we took 1st in the races. My son was very excited! It was close though, which admittedly surprised me.

I did my best with rear wheel tuning, struggled... Any advice or thoughts on where I should focus my efforts are appreciated! YouTube short of the final race (with 2nd place riding my back) is linked below.

I've watched this clip several times - Neat! You appear to be leading by about 1/4 car length off of the incline and maintain that lead through the straightaway. I would be willing to attribute much of that initial lead to the use of lightened wheels? Although, as other noted, it is not clear how the lathing was executed (Q: was the wheel diameter significantly reduced?).

Just based on your excellent descriptions of the situation, I think that improved performance in the flat could be gained by more refined wheel alignment, notably with the rears. We've found that a jig designed to drill cambered axles is a good investment for that (maybe your competition used one?).

[Hyperfocus]

Result from Saturday was we took 1st in the races. My son was very excited! It was close though, which admittedly surprised me.

I did my best with rear wheel tuning, struggled... Any advice or thoughts on where I should focus my efforts are appreciated! YouTube short of the final race (with 2nd place riding my back) is linked below.

I've watched this clip several times - Neat! You appear to be leading by about 1/4 car length off of the incline and maintain that lead through the straightaway. I would be willing to attribute much of that initial lead to the use of lightened wheels? Although, as other noted, it is not clear how the lathing was executed (Q: was the wheel diameter significantly reduced?).

Yes I'd say the lightened wheels were the biggest factor for the incline lead. I will check the diameter vs. stock later tonight.

Just based on your excellent descriptions of the situation, I think that improved performance in the flat could be gained by more refined wheel alignment, notably with the rears. We've found that a jig designed to drill cambered axles is a good investment for that (maybe your competition used one?).

I am checking into some cambered jigs, though my only holdback is being limited on degree of camber. I was certain I canted my rears 3 degrees but they certainly didn't look very angled on the car haha. I am trying to find an STL to 3D print a jig for drilling, otherwise I will check my options. I am keen on trying Stan's method for alignment, though.

Overall I was surprised that my performance on the flat wasn't better given my use of Max V's Krytox mix, and polished bores/axles. Car in 2nd place was definitely just using WD40, likely no polishing of bores or axles. Although I will have to inspect my bores, they didn't look great even after polish... pictures will come later for you guys to give your thoughts.