When modifications don't seem to work

Your doing what I normally like to do and thats take a slow car and make it fast.  What Ive learned is that often, whats making that car slow is the wheels, or in all honesty, one wheel being wobbly.  You can do all the magic you want and itll never fix a wobbly wheel.  Also, it seems that sometimes there is nothing you can do to make a slow car fast.  I have a Caddy V16 thats been abused and a brand new one.  Ive done all the tricks and that sucker is still nowhere near as fast as a straight outta the package new one.  Just is what it is.  

That said...DONT give up.  Use it as practice and keep pushing.  Eventually you will succeed and itll be worth it.  

Look for some wheels that roll straight and smooth and then see if they dont make a difference in that car.

Matt

Yes...start with Wheel Farming...the fastest cars are always quiet...spin your axels...if you hear them...car could use a new package(axel/wheel combo)...also, some Mods need to be seasoned and may be a better car after several runs or races on the build.

I'm often in the same boat...I get excited to build a car, put it together, think it looks cool and I did all the right science for it, and - nothing. I watch a stock car of the same casting blow right by it. It can be discouraging but like Matt said - don't give up. They say it's the journey and that can't be more true with modding.

Science, she is a harsh mistress! It's been very interesting to see the science scale down to the Hot Wheels size. I never paid much attention to wobbly wheels...at least, not so much as to go through car after car looking for perfectly smooth ones. Even though I knew better, my attitude was always, "it won't matter much," because the other stuff matters more, but not always.

I was keen to spot things like a car that's banging against the walls or where the weight is located - all the visible stuff - but I never really took the time to dig in and analyze things at a smaller level. Part of that is ignorance and the other part of that is lack of patience (aka lazy). Making your fast(er) really is a trial-and-error process...trying something, testing, adjust, test, adjust, test...etc. I don't naturally have that mindset and it's been tough to change.

However...a gotcha of sorts is that what's not fast on your home track might not be the case on other tracks. Yes, science is true no matter what, but just because your car doesn't go fast(er) on drag strip doesn't mean it won't do well on a road course - or vice versa. Everyone's track is different and each has its quirks...and a lot of that is a straight up guess. Just gotta try, watch, and try again the next time.

But all that is to again say - DON'T GIVE UP. It can be discouraging but a lot of the fun is tinkering with toy cars and trying to make them better. 

So could it be that even though I'm using brand new wheels and axles, there are just some minute wobbles that I'm not seeing that are slowing the cars down? I don't think I've ever had a set of axles that weren't noisy by the way.

I'm a high school math/physics teacher and drove real racecars for nearly 20 years, and I can't figure out 1/64 scale. It just blows my mind that I can take a car that is twice as heavy, put a new set of wheels and axles in them, lube them, then watch it be 15% slower down the track than a stocker with dry axles and half the weight.

Also, I don't know if I'm cut out for this. It hurts inside a little every time I pull a perfectly good car apart just to rob its axles.

You won't find perfect wheel/axle combos at all but some are certainly less wobbly than others. It's not something I ever paid much attention to, to be honest. I mean, I knew when the wheels were straight up bad and slow, but other than that, I didn't try too hard at it. I put more focus on weight placement and straight running.

And the other thing I do is not care too much. Sure, I'd like to win but given I don't have access to the tracks I'm running on, it's a guess no matter what I try. I have fun taking them apart and putting them back together. I test it as best I can on my track and sometimes the results aren't great but then tell myself, "what the hell," button it up and send it on its way. If I lose, I lose. The process was fun and maybe I learned something for next time. 

The more I test, the more confused I get. I ran two races this weekend with friends bringing over stockers. We ran two races with 20 cars, and the first set was won by the lightest car in the bunch, a Roll Cage, an offroad buggy with knobby tires. Second place was a Super Van art car. The next race was won by a lightweight spider man themed buggy that I didn't catch the name of. 

It all just depends on the a) the track, and b) the quality of the car. You can take 10 castings of that buggy and none of them will perform the same. Weight alone doesn't dictate which car will be faster. All the weight in the world won't matter if the wheels/axles are crap. Also where the weight is located. Lots of factors that I agree can be frustrating.

Plus things like wheelbase, width of the car...you can outline all the attributes that a fast car should have but finding/making a car that has them all is nirvana - and damn near impossible. So I think the way to go about it is prioritize which of those traits is most important and focus on the top few.

Here's an article from a few years ago that includes a video of a super smart science guy talking about the physics as they apply to pinewood derby cars. All of that should scale down because physics is physics. But he breaks down the factors that seem to make the most difference so you can have idea where to focus efforts and which things you shouldn't bother with.

I doubt it translate 100% to Hot Wheels but it's probably a good place to start your trials.

Yep track conditions are key.  When I had a simple starting line with a free/unsupported drop down to the ground (look at pictures of the 60's play sets Mattel offered) then I noticed lighter cars would often rule.  When I finally added a long board to make my incline then the list of fast cars was completely turned on its head and all the heavier challengers came back to claim their places higher up the list.  Whats fast on my track often doesnt translate on the Hot Wheels 6 lane my Dad keeps around for my Son and Nephew, or if you watch the 55/57 Chevy Nationals, my car that made it to the Finals seemed to flounder at Red Pill's track the next round.

Matt