Scalextric Mustang Tuning

[perrotoro]

I've been tuning (off and on) for a couple of months on a Scalextric Mustang for Carrera track, w stock magnets, adding chip for digital mode. My objective for all my cars is sub 6-second laps with 5.5 to 5.7 second laps being my best performers. Note: I apologize if this is the wrong sub-forum - I may have overlooked a tuning forum.

I basically tune without the body first knowing that running with the body will almost always add ~0.5 seconds to the lap times. For this car, the chassis-only runs are a comfortable 5 seconds. This should equate to a 5.5 second lap with body-on. But, I'm having trouble getting sub 6 second laps with this car with the body attached.

I'm a home-only racer, so club-rules allow for scraping the under side if the body and this body appears to have a higher COG. I scraped enough material to reduce the weight of the body from 20 to 15 grams - mostly from the under side of the roof. (What's the term for scraping with a razor knife - can't remember.) But this lowering the COG sdid not help - times remained the same. (BTW, I've not had to scraped most of the fleet for the 0.5 second lap adder to apply.)

So is there something else to try? Is this body possibly contorting the chassis into a poor performance geometry when attached. I see I have a little room between the rear wheels and the rear wheel fenders. I could take a little off the body posts to lower the COG a bit more, but it appears I'd have to take off a similar amount off the mate-up between the body and chassis to accomplish this, and that might get messy.

Any ideas appreciated. Thanks.

[Aptosc6]

Planing is the term you couldn't remember.

I have this car and have run it on a wood track for TransAm. Tires are likely your first place to start. Use what works best in your club.
Other points to review, body float side to side and front to back. Maybe 1/32 inch all around. It helps to remove any body sections from the chassis and to reglue them onto the body.
Pay attention to the interior and how it interferes with the wiring and chassis.
If your rules allow it replace the guide. This mod requires some fabrication.

[perrotoro]

Aptosc6 - there was a term I saw in a video that showed using a razor knife to scrape a little off the body to create a separation at the chassis mate-up. It was a term that I don't think I heard before, but planing works for me too. I'll have to re-find that video.

Replaced tires - but that shouldn't have too much impact on body vs no-body times - right?

I did re-glue body to chassis connections.

Tried the float technique with a very loose screws (2-front, 1-rear body to chassis) and times weren't improved. I've tried this before - I think I saw a few years ago that float for pod to chassis was not critical for stiff plastic track. The chassis alone runs better than average times, but adding the body cause the rear to get loose - significantly more than the average for the rest of the fleet.

I don't see any interior interferences.

I did replace the guide - I wanted to add a spacer to the original guide and damaged it a bit during removal. I did not replace it with a deep wood guide - its a post type guide - not screwed. I may replace this again with a deep screwed guide but I don't think this will help too much with rear looseness. I noticed these two post guides showed minor rotational friction and lubricated the 2nd with graphite. It's still slightly more friction than normal - this might be another reason to replace it. Still, I don't see how this would affect rear looseness significantly.

[docdoom]

are you allowed to replace the interior?

[Aptosc6]

I dug out a picture of the insides of my Mustang (attached).
One thing I forgot to mention is this car is narrow compared to most of the other cars used in TranAm. That makes it a little more tricky in the turns.

[perrotoro]

Aptosc6 - car and chassis are likely longer - I’ll ck when I’m back at home.  But still, the chassis alone runs superior times. My Scalextric mustang is one of the more recent offerings. I’ll post pics

[dreinecke]

I've written a few articles over the years. Let me know if you have any questions!

The first starts with the 1970 Camaro, but also shows the Mustangs.

RMS Trans-Am Tuning.pdf

[Zippideedooda]

Excellent article sir.

[dreinecke]

I've also done the Challenger:

RMS Scalextric Challenger Tuning.pdf

[dreinecke]

...and the Cougar. This one needed work out of the box as well.

RMS Scalextric Cougar Tuning.pdf.pdf

[one32]

dreinecke
Outstanding tuning info on the 3 t/a cars. Thank you so much

[perrotoro]

[perrotoro]

Body/Cockpit/windshield = 25 grams, formerly 30 grams.

[Aptosc6]

OK, different beast.
I recentIy tuned a Javelin which is in line drive. I added some weight up parallel to the motor on both sides of the chassis. Also, found the rake and front tire diameters have profound effects on keeping the car planted in the turns. Try to get the guide and front tires to create a plane with the rear tires. I use the term "that you want to be able to plant an elephant on the guide screw" without lifting the rear tires at all. Good luck.