Modding a Ferrari, wheels and weight

redlinederby Saturday, 1/4/2020
Site manager

For the Super Cars race, I picked a Ferrari Testarossa that I had in my stash. It was old and beat up with some Ultra Hot wheels, but the axles were shot. Figured a basic wheel swap and added weight would be sufficient. It had been a while since I've modded anything so it seemed good for getting the rust off.

No real amazing insight here, just a story of how I went about taking this thing apart and adding a few things. If there's anything I took away from this one, it's using screws to keep the thing together rather than the typical epoxy. It let me do some tests with weight before settling on a final state. 

My first disocvery was the lower rear of the car was plastic...two mold plastic, to be exact. I didn't pay that close attention to it when I picked it, but whatever. I thought the lack of weight might be a problem but made up for it later.

The plastic turned out to have its benefits, like creating a perfect little pocket for some weight. It kept the weight a little higher than it would otherwise, so hopefully that will help.

After some more trims of plastic, I had the thing mocked up with some FTEs taken from another Ferrari. Looked good to me. 

Next step was fixing the FTEs in place. I mixed up a few dabs of JB Kwik as usual, put it on the chassis and them laid it on the axles while on the RLD Alignment Jig and waited. I learned to put the chassis upsidedown on a jig to get the most out of gravity, but I've been asked if the epoxy drips. You can see here that the epoxy does "sag" but it doesn't drip. It cures fast enough and is thick enough (it shouldn't be too runny).

Once the epoxy set, I could flip it over and work on getting the interior and weight into place for testing. I used hot glue to place the weights so they'd hold during test runs. Hot glue is great because it holds well enough but can easily be pried off without injury to the car. Just pops right off.

Next step was some test runs. I used drilled some screw holes into the body posts and then followed Matt's directions for "force tapping" with some 2-56 screws and it worked great. I didn't drill down far enough at first, so I used some small plastic washers to make up the difference. It turned out nice and tight. It's wonderful to have the ability to button up, test, and take apart without much hassle.

After a few runs and testing out some difference weight positions, I settled on final setup and glued everything that wasn't yet permanent. Super glue on the plastic parts and epoxy on the metal.

I have my doubts how well this will do on Bootleg Run. It's a road course and I wonder if the weight will actually help or harm performance.

And of course, when I tested this thing on my drag track, it didn't always win - even against stock cars - which is the story of my modding life. A few hours of fun playing with tools thinking you're making a premium car only to find out you're no better than a generic coupe. 

But's fun to mod all the same. I'll report back with performance after the race!


Fantastic write up 

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Mattman213 1/4/20

Ha that's my modding life!  Think I'm building a real head turner and it ends up being a turd.  Then I slap something else together and it burns the track down.  I love that Testarosa casting so even if it's not a champ you brought it  back and that's awesome by me!


  • I love Ferrari castings, I have a ton. Always liked them so when I got back into HWs, I bought them when I saw them. — redlinederby
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WorpeX 1/6/20

Used my RLD Alignment Jiggy to rebuild my Speed Blaster mod last week for the first time. It really helped a lot! Everything is definitely lined up much better. I will say, maybe on the next iteration on the jig, it would be nice if there was a lever for moving the track. It can be annoying to move it when the car is sitting on the jig. I kept bumping the car off with my finger! 

As for the build, you might actually be better off removing the front weight on the seats. Ideally you want the weight as far back as possible so if you can put it with the rear weight that would be best, but if not, just removing it completely might help.

Also, do you sand the wheels at all? I've never done that, but Mattman did when he sent his GMS Chevy Stocker to me and it seemed to help a ton with track speed. Would love to see a guide on that!

  • Thanks for the jig feedback. The slider is tricky cause you don't want it too loose either. I'll see what I can come up with. — redlinederby
  • On the GMS car I very very very lightly touched them to some 1500 or 2000 grit to try and knock off some casting slag/imperfections that were causing a romp romp romp noise. Amazing what a very slight sand will do if you have noisy wheels, Im betting that Stocker woulda picked up a tad more had I done a full sanding! Take a long (tall) piece of sand paper and sand in circles going up and down the piece of paper till you are happy. redline posted some great links below which are where I got my info! — Mattman213
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redlinederby 1/6/20
Site manager

I've tried to sand my wheels but I don't think I'm doing it right. It just looks janky and probably harms things more than helps.

But, there are few posts about sanding wheels, you can start here and there's some more links in there too.

And here's another post with a video from C10 about how he sands wheels.

  • Awesome, ill check them out! — WorpeX

Where did you get the screws from ?

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