I will be running one of these in the Thunderjet 🙂 series (see photo)

Here’s my ride(s).

The rules call for “OEM Guide (GU001) and new THGU00 deep wood guide allowed”. Can I use the GU002?

GUIDE FLAG WITH SCREW 2mm x 8mm, Part: GU001 -or-
GUIDE FLAG WITH SCREW 2mm x 8mm FOR CARRERA AND WOODEN TRACKS, Part: GU002 (LEB is the only retailer with this guide in stock)

I have a question about wheels and tires are these the OEM ThunderSlot wheels and tires? Can I use any of these?

Lola T70 MKIII, CAN-AM 350, Lola T70 CAN-AM

Wheels – Front
NYLON FRONT RIMS, Part RMF001PL

Wheels – Rear
ALUMINIUM REAR RIMS, Part RMR003AL
ALUMINIUM REAR RIMS, Part RMR002AL

Tires – Front
HARD LOW FRICTION FRONT TIRES 9mm x 16mm, Part TYR003FR

Tires – Rear
SLICK RACING REAR TIRES, Part TYR004R
CLASSIC THREADED REAR TIRES, Part TYC002R (CAN-AM 350 Only)

I found this information on the ThunderSlot site (https://www.thunderslot.com/en/home-en/)

Oh, one more thing. I may have only one car I can race. My CA00106S/W, Lola T70 MKIII is not listed but others are like the CA00101S/W. Can I race mine?

Guys,

I disagree with the decision to disallow the Slot.it wheels on the front of the Thunderslots.  We allowed them the last two times we raced Thunderslot in 2020 and 2022.

Russell

The rules on the front wheels have been updated.  Slot.it 15×8 aluminum wheels are allowed.  There is also no minimum body weight.

Let me know if there is anything else you all want changed.  I honestly don’t care about the series and will run any rules any of you would like to run.

I know Randy is going to give me shit for my “non racecar” pain aesthetic, but this T70 is what I have in the works.  And yes, if I can figure out it out my alien friend will be driving.   

I will hopefully be running this car.

Can a Chaparral body and wing from another company be used on the Thunderslot chassis for this series?

I l0ve that body color, but you may need to perform surgery and/or get a dispensation for the driver and Lexan interior.

I am using inserts from our previous series that are racing mag wheels that I saw in an old picture.  If that is upsetting the scrutineer, let me know early.

Regarding the magnetic downforce issue we discovered yesterday –

While almost all of us went over, it seems like there is still a fairly wide variance with going over.  Correct me if I’m wrong, but I remember the highest being in the high 40s or maybe even low 50s?  Mine was at 31 and John’s was the only one within the standard limit of 30.  20 more grams of magnetic downforce seems to be quite an advantage to me, even if I am relatively new to this.  I don’t really see it as being reasonable to ask everyone with magnetically hot motors to buy replacements until they find one that’s within the limit.  Equally, I don’t see it being reasonable for people that end up with motors with lower magnetic downforce to buy several until they get one comparable to the higher numbers.  That seems counter to the spirit of a spec series.  Is it sacrilegious for me to suggest we up the limit to reflect the maximum we saw with a stock motor and allow those with lower numbers to run magnets to match that downforce?  There’s lots of teeny tiny magnets available to fine tune it.  I learned the art of this in Houston.

Mel,

That is an interesting idea.  One of my concerns is the placement of the additional magnets so the downforce is at a similar level and in the same location.   The other issue is the ability to do this work at home without a Magnet Marshall.  I think it might be time consuming to have everyone try to use the Magnet Marshall before a race.  We would have to have a deadline by when all the magnet tuning would need to be completed by.

I would like to get input from the club before the next race so if we decide to move forward with magnet tuning to level the playing field we do so before the race so we all know how it will work moving forward .

Was the magnetic down force specific to a model that put the motor at a unique location above the track?  Or was it a batch of motors that are stronger magnetically.  My Elva motor is faster on the dynamometer than my Lola for no obvious reason.

Marty,
I was also thinking about the placement issue after I made that post.  We’d have to approach it in such a way that we are replicating the downforce of the motors in as close a fashion as possible.

Radial TA,

From what I observed, it was across a wide variety of models with no discernible correlation to a specific model.  It could be a batch of motors if this was from a series where everyone bought their cars around the same time.

In general –
I’ve heard tales about how fast the Thunderslots are and how well they stick to the track.  I think we might have an explanation for that now.  I will also be very honest in acknowledging that my car was not tuned worth a damn and y’all are excellent drivers and tuners.  I don’t want to sound like “Mr. Sour Grapes” because I got smoked, but I think it’s all worth considering.

I think the downforce issue is dark hole to go down.  We ran Thunderslot 4 times before last Saturday and we never had a limit on downforce

By far the biggest factor affecting downforce is tire diameter.  Downforce is inversely proportional to the square of the distance  between the motor and  the braid on the track.   If you halve the spacing the downforce would be 4 times as strong.⁸ To decrease downforce, true tires to a larger diameter.  With the Thunderslots I think we are all using as small  a tire diameter as we can get without the chassis or spur gear dragging.  Motor pods in a series with adjustable offset ùmotor pods, the downforce would be adjustable.  I think trying to adjust downforce with magnets would be a futile exercise.  Buying extra motors, mounting them in a chassis to find acceptable downforce would be expensive and probably also futile.  We ran the series 4 previous times with no limit on downforce and my preference would be to “forgit about it”.

Russell

After my previous post about considering a mag level and ride height,  I read Russell’s post. He is absolutely correct.  “Forget about it”.

Lotus Jr.

I agree with Russell  we have taken downforce before

Having trouble sending pic

its of a pic in 2019 checking downforce

All, in the spirit of fairness, I don’t see why someone couldn’t add small magnets to slightly increase magnetic downforce. We could simply set a new maximum for Thunderslots.

Do I believe this will improve or decrease performance? We’ll only know by testing.

It’s unfortunate that we have such large variances.

I defer to the experienced experts on this.  The large variances are unfortunate because it does make one wonder.  I’m going to do some of my own testing and experimenting with it.  If it makes a big difference, maybe somebody can loan me a stick of Beemans for pushing Deep Purple past the sound barrier.

At a cursory glance from the results in the past, it does not seem that the downforce gives a distinct advantage.  In a deeper dive, could look at the car weight / downforce ratio and see what comes out of that, but I teach maths all day and don’t feel like doing it right now.  I appreciate that y’all are willing to have some dialogue.  I learn from these discussions.  If the consensus is that it’s a rabbit hole not worth exploring, I’m going with Russel’s notion of “Forget about it.” 

Has anyone drilled the front wheels and used a grub screw to tight front wheels onto the axle? Also, would that be legal?

Kim, it is unlikely anyone will notice the grub screw on the nylon wheel, so it has probably not been discussed as a legal issue.  I know that to use the existing axle I didn’t drill out the wheel bigger, I ground the knurled ends smooth to maintain good fit.  I don’t remember if/how I drilled a grub screw hole.

Kim,

I wouldn’t worry about putting a grub screw in the plastic front wheels.  I have yet to see a wheel come off of a Thunderslot car.  Both Ary and I are running the stock wheels with no issues.  I would leave the front wheels and work on getting the car set up for the track.  Just my opinion.

I would be interested to know if the Magnet Marshal as any real world correlation with actual magnetic downforce on our track. One is a large steel bar, flush with the scale’s surface, and the other is a small steel wire embedded in copper braid, slightly below the track surface. Is it all just snake oil anyway?

The Magnet Marshall is just a tool to show the relevant magnetic downforce created by the motor and/or magnets as compared to other cars.  It’s not necessarily a real world example of the downforce you would get on our track as the braid depth is slightly different but its not meant to be a tool to tell you the exact downforce for our track.  It’s a tool that is designed to give you a relative number compared to the other cars you are testing.  When used this way it is highly relative.

Concerning magnetic downforce:  There will be no changes to the rules other than the stipulation that no part of the chassis or motor pod can ever come in contact with the track.  This means the rear tires have to be of a certain size to make sure this happens.  The smaller the tires the better the magnetic downforce but then you run the risk of contacting the track and having your car disqualified.  Just make sure your tires have enough rubber that the chassis will not come in contact with the track before and after the race.

What the heck happened?  Was that from an alcohol bath to strip the paint?