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FRONT TIRE RUBBING
You are allowed to remove the studs and trim the back of the light buckets and add a washer to the front post if needed.
GT3 FRONT TIRE RUBBING"I cant drive 55!" Sammy
NSR TIRE TRUING NOTES
COMPATIBLE NSR TIRE TRUERS"I cant drive 55!" Sammy
Russ – I have previously trued NSRs on my P&N (such as for the NSR rally series) and don’t recall specific problems. But truing the NSRs on the P&N may have made your hubs microscopically oblong, or maybe the tires are just wonky (shifted during the truing process).
For this series – I trued my stock NSR Super-grips (brand new C7R Vette) on the HUDY.
I added Thunderslot ‘foam donuts’ to fill the gap and lightly ShoeGoo’ed the tires.
My Supergrips seem to be shedding/marbling and hence chatter a little in straight line. They also require a good rounding to prevent chatter in the corners.
The Moslers and 917s seemed easier to tune. Today – I can hit 4.1s immediately with my 917. When the tires and motor warm up (50 laps?) it runs consistently in the mid 3.9s without trying.
Both 917 and Mosler have a lower CG and dont have the big caboose as compared to the Vette."I cant drive 55!" Sammy
RUSS – yes I too spent several hours this Sat & Sun trying to either a) break 4.1 or b) have a car that did not jack-rabbit in the straights or fishtail in the corners. The Supergrips marbled a little and contributed to both the jumps and slides.
After too many 4.4s, I switched back from the 22k motor to the 25k OEM motor; and went back and forth from the 32z (OEM) to 31z spurs. With the 32z I could barely break high 4.3s; with the 31z I clocked a few mid and high 4.2s but mainly stayed in the 4.3s My pinion is a 11z (OEM spec).
I also experienced more rubbing on the front tires (I need to double-check to see if I am running the 17mm or 19mm NSR-No-Grips)
"I cant drive 55!" Sammy
TA – of course we will race it : )
We will put it into rotation and select one or even perhaps 3 people (proxy style) to drive it.
…
I will be closely checking your Reifen to ensure they are legal – no experimental BFG compounds are allowed … no gluing NSR over the original sidewall names etc."I cant drive 55!" Sammy
Hey – I hate to drop this on you guys but here’s some calcs that defy the recent idea of using the 22k/21.5k motors (at 11v). Since we are using S/W gears our options are limited.
Also – I did the numbers using 12v and 11v and not surprisingly, 11v favors the 25k motor and 12v favors the 22k/21,5 motor.11 VOLTS
25,000 motor rated, * 11/12v = 22,800 effective
Rear wheel RPM Ratio Spur/pinion
8085 2.82 31/11
8056 2.83 34/12
7835 2.91 32/11 OEM/Stock22/21.5 rated, avg of 21,750 * 11/12v = 19,938 effective
Rear wheel RPM Ratio Spur/pinion
8100 2.46 32/13
7975 2.50 30/12
7728 2.58 31/1212 VOLTS
25,000 motor rated
Rear wheel RPM Ratio Spur/pinion
8091 3.09 34/1122/21.5 rated, avg of 21,750
Rear wheel RPM Ratio Spur/pinion
8146 2.67 32/12
7967 2.73 30/11
7713 2.82 31/11So – at this point I am thinking we should stick with 11 volts since if most people have stuck with the stock motor there are less gear combinations they have to experiment with.
IDEAS?
"I cant drive 55!" Sammy
TUNING NOTES
MOTOR – At the series voltage of 11v, some people testing Vettes are experiencing the 25k motor to be “too-hot” (jackrabbit hops and fishtails); even with Low gearing (e.g. the OEM 32/11 = 2.91 ratio, or 33/11 = 3.0).
Conversely, the 22k or 21.5k motors may need Higher gearing (2.82, 2.73) to go below 4.3s.BALANCE – the nose on the Vettes are light, so some weight behind the guide (~3 to 4gm) or on the nose of the motor-pod (~ 5-7gm) may be something to experiment with.
"I cant drive 55!" Sammy
SM COMMENTS:
ERIK (and others)
1 Re BMW-#1 Z4, if you are planning on the White Presentation livery- that should be NP.
2 If you can attend, great – yes show up masked and enter the fray.
3 If you cant (b/c of the kart race) – you can either drop that Round (the normal process) or leave your car and ask someone to be your Driver for round-1.
4 In general, anyone wanting to field a car but not able to attend (regardless if due to Covid, health, travel issues); they can hire another member as their driver.(I am considering hiring John to build my car and Steven to drive – based on recent GP-C history LOL. I will deal with sponsors, organizing the VIP Tent and post race parties etc.)
Seriously – if you want to enter a car but cannot attend in person, reach out to another member … let’s keep this simple and ‘easy’
"I cant drive 55!" Sammy
SAMPLE TAMIYA MINI/JR-4WD RACER
— Owner built and customized. All but the least expensive and basic cars are in Kits (like Tamiya RCs cars. High quality as is typical of Tamiya.)
— 3volt FC130 motors range from 10,000rpm to over 30,000rpm (My car: 10k installed for testing at HobbyTown, alt. 14k and 24k motors can snap-in w/o soldering)
— TUNING PARTS
Cone profile tires to change corner handling (depending on if the large diameter is on the outside or inside of the rim); Ball bearings for axles and transmission gears; large-diameter Rollers (with ball-bearings) to guide car in channel; high-rollers stabilize car in high-speed corners; ball shaped Cap-nuts bounce the car back into the lane/channel and reduce scratching of track; ‘Brake-pad’ in rear reduces ramp speed during a jump; Damper-weights absorb impact during landing and speed up wheels to contact track after a jump or a partial de-slot; additional arms attached to allow installation of Rollers as wide as possible/legal.
.
CHASSIS
TRACK – typically Three lanes (in major meets, five are common; two lanes for a home track)
A single serpentine lane appears and functions as three-distinct lanes; usually channeled with at least one lane-cross-over bridge. Competition circuits have jumps, complex esses, wall-climbs; some have loops;"I cant drive 55!" Sammy
NEED RSVP – ‘register’ for NSR-GT3 race.
We need to balance out all the good-ole-boyz Vetts with some:
ASVs(AMs), R8s (OoOoO), Z4s (Bimmer), Mercs, 997s (goenfausten)"I cant drive 55!" Sammy
NAME: suggestion – “Mermaid” since the upper loop kinda looks like a woman’s head; then the straight with esse looks like a mermaid’s tail. [Circuit de La Sirena]
-or- “Mobius Prime” – the continuous eight is a mobius, but since its L-shaped maybe add the ‘prime’ from the Transformer movies.
"I cant drive 55!" Sammy
Tough luck Marty! Who is coming up on you, Ary or Shawn?
Nice looking car, but that pan looks so aerodynamic I need to check the rules on it …"I cant drive 55!" Sammy
SETUP NOTES: After 20 minutes of painstakingly adjusting my axle/tire height, when thumbing my front tires with the car on its back, I discovered them rubbing the oddly shaped light buckets. Carefully grinding down all the various bumps from the bucket will be Permitted to resolve the contact; as well as adding a thin washer to the body post; or other innovative ideas. NO, truing the tires some more did not completely remove the contact; and I am running the stock size NSR-ZeroGrips. Note: I did Not have this contact issue with my C6R in 2016.
WEIGHT TUNING NOTES: My C7R Wheelbase is 85mm (axle to axle). Centerline is 42.5mm, appx 2mm forward of the Drop-Arm pivot (The Centerline is placed over the middle of the gap between the scales)
My C7R Vette weighs 75gm; the textbook weight distribution is between:
Front 40% / 30gm Rear: 60% / 45gm
Front 45% / 33.75gm Rear: 55% / 41.25gmAs stock, my car’s distribution was:
Front 36% / 27gm Rear: 64% / 48gmAdding 5gm to the nose of the pod[1]: car=80gm
Front 40% / 32gm Rear: 60% / 48gmNOTES: Each model will have different centerlines; each car will have unique weights. Depending on the location the weight is added, will affect the front/rear balance[1]; weights on the Pan “wings” may be easier to tune than a single weight on the motor pod.
"I cant drive 55!" Sammy
Thanks Randy and Russ! Is anyone going to field one of these? ASVs, R8s, Z4s, Mercs, 997s
"I cant drive 55!" Sammy
Looks great Randy; looking forward to you racing 1×1 again!
P.S. If anyone is using the Thunderslot Foam Donuts; the “donut holes” can be trimmed to be used as Wing supports.
— Cut one edge flat; measure wing strut length (appx 4-5mm); cut bottom flat; trim leading and trailing edges with angular cuts. Keep width to match the top (fattest part) of the struts.
— After the angles look good; glue to the inside of the wing struts with a small dab of ShoeGoo.
100% Optional"I cant drive 55!" Sammy