USGT
#3541
Tech Fanatic
Joined: Aug 2008
Posts: 903
From: San Antonio, Texas
The Audi driver (Mike Skeen) finished 4th in the Sunday race, which was in wet conditions. He Had a great battle for 3rd throughout the race. Also check out his YouTube channel. He has some excellent in-car or on-helmet videos he posts up of every race.
Regarding the wing mounting- I noticed that too. It has been done on prototypes for some time now, and some gt cars as well. It is because mounting to the bottom of the wing disrupts the pressure differential resulting in less downforce across the rear wing. In RC this doesn't matter as our "wings" are really just spoilers to create downforce. If we had an actual wing profile, then it would matter where the mount is. But who knows how much of an effect that would have at 1/10 scale.
Regarding the wing mounting- I noticed that too. It has been done on prototypes for some time now, and some gt cars as well. It is because mounting to the bottom of the wing disrupts the pressure differential resulting in less downforce across the rear wing. In RC this doesn't matter as our "wings" are really just spoilers to create downforce. If we had an actual wing profile, then it would matter where the mount is. But who knows how much of an effect that would have at 1/10 scale.
I have the race recorded for tomorrow, at least now I know how Mike did. PS the race is on CBS this year not NBC for anyone looking for it. Makes sense since the wing on a car is an upside down airfoil and putting the mount on the bottom side of the airfoil (i.e., the top of the car wing) keeps the air flow speed over the airfoil maximized and slows the airflow under the air foil thus creating the max lift (or down force in this case). Cleaver German engineers. With the difference in Reynolds numbers between the 1:1 scale Audis and our 1/10th scale cars, I doubt the effect would be worth the effort on our model cars. One other thing I noticed what that the paint job on Mike's car wasn't smooth and polished shinny as I saw on the GMG cars.
#3547
#3548
I think it's just the poor quality of the photo. The tires have nearly all of their tread. I thought it was amazing. I'm guessing it's because they were covered in so much crap, the rubber was not actually making contact with the carpet
#3550
#3551
Btw, I forgot to mention, the car was nearly perfect the entire run. The only issue we had, was while I was driving during the 2 hour night section. Car started to get hard to drive, and then eventually it was plowing like crazy into every corner. Shortly there after I hear the RD announce that someone lost a wheel. I immediately knew what was causing our handling issues
I pitted, we re-attached the front wheel, made sure the rest of the nuts were tight, and off we went
I pitted, we re-attached the front wheel, made sure the rest of the nuts were tight, and off we went
#3553
Tech Addict
Joined: Nov 2003
Posts: 638
In sanctioned/organized racing venues (ROAR/EFRA/IFMAR) the maximum width of a 190mm body is actually 195mm and in the 200mm class the bodies are allowed to be 205mm. Most body manufacturers try to be right out there as wide as possible.
In the USGT / GTSpec type classes there are no rules pertaining to width. When we did the LFA body the GT class was still kinda fresh and just starting to gell. I was kinda guessing at what would work best - thus the LFA is a true 200mm body. (guessed wrong....oops) Since then we are trying to do PROTOform GT bodies in a more optimum width, to hopefully satisfy as many USGT fans as possible.
Since the LFA body release it became apparent that a 190/195mm GT body was the way to go, so that's the direction we went. However, I've also noted a bit of a down-side to that width as explained below. So many enthusiasts of this class really dig the realism factor, so in the case of the PFM-10 we intentionally made the front 1mm wider per side and the overall rear width approx 3-4mm wider for a couple reasons.
- in order to have realistic rear fender shapes (with a proper amount of "roll-under" behind the rear wheel openings) it automatically creates a potential "body-tuck" type situation (which we all hate
) By merely adding a few mm in that area we have hopefully created a better compromise between form and function.- Some GT enthusiasts like the staggered wheel look. Now it's tad easier to emulate the way real 1:1 supercars look with their wider rear wheels. Now 31mm rear wheels can be used if you so chose. (there are tons of them in the rc marketplace)
- From a performance standpoint, thin spacers can now be used to slightly space out the track width and possibly gain a bit of cornering stability.
I hope that helps you understand out logic here at PROTOform. We love this class and are currently hard at work on new USGT styles.
QUESTION: Do you think that we should do a 190mm version of the Lexus LFA? It would have a few updates to the aero package as seen in the real world but would essentially be 90% the same, just narrower.
Thanks for you input and comments! Much apprecuiated.

Dale Epp - PROTOform
#3554
for the molded HPI wing, the one that comes with the various risers in it, is there one that is more optimum to use as far as height goes than another?
Mounted this to a mccallister corvette with the tallest one, but curious if a different height would be better.
Mounted this to a mccallister corvette with the tallest one, but curious if a different height would be better.
#3555
Joined: Aug 2001
Posts: 8,854
From: In a land of mini-mighty mental giants
Hi Guys;
In sanctioned/organized racing venues (ROAR/EFRA/IFMAR) the maximum width of a 190mm body is actually 195mm and in the 200mm class the bodies are allowed to be 205mm. Most body manufacturers try to be right out there as wide as possible.
In the USGT / GTSpec type classes there are no rules pertaining to width. When we did the LFA body the GT class was still kinda fresh and just starting to gell. I was kinda guessing at what would work best - thus the LFA is a true 200mm body. (guessed wrong....oops) Since then we are trying to do PROTOform GT bodies in a more optimum width, to hopefully satisfy as many USGT fans as possible.
Since the LFA body release it became apparent that a 190/195mm GT body was the way to go, so that's the direction we went. However, I've also noted a bit of a down-side to that width as explained below. So many enthusiasts of this class really dig the realism factor, so in the case of the PFM-10 we intentionally made the front 1mm wider per side and the overall rear width approx 3-4mm wider for a couple reasons.
- in order to have realistic rear fender shapes (with a proper amount of "roll-under" behind the rear wheel openings) it automatically creates a potential "body-tuck" type situation (which we all hate
) By merely adding a few mm in that area we have hopefully created a better compromise between form and function.
- Some GT enthusiasts like the staggered wheel look. Now it's tad easier to emulate the way real 1:1 supercars look with their wider rear wheels. Now 31mm rear wheels can be used if you so chose. (there are tons of them in the rc marketplace)
- From a performance standpoint, thin spacers can now be used to slightly space out the track width and possibly gain a bit of cornering stability.
I hope that helps you understand out logic here at PROTOform. We love this class and are currently hard at work on new USGT styles.
QUESTION: Do you think that we should do a 190mm version of the Lexus LFA? It would have a few updates to the aero package as seen in the real world but would essentially be 90% the same, just narrower.
Thanks for you input and comments! Much apprecuiated.
Dale Epp - PROTOform
In sanctioned/organized racing venues (ROAR/EFRA/IFMAR) the maximum width of a 190mm body is actually 195mm and in the 200mm class the bodies are allowed to be 205mm. Most body manufacturers try to be right out there as wide as possible.
In the USGT / GTSpec type classes there are no rules pertaining to width. When we did the LFA body the GT class was still kinda fresh and just starting to gell. I was kinda guessing at what would work best - thus the LFA is a true 200mm body. (guessed wrong....oops) Since then we are trying to do PROTOform GT bodies in a more optimum width, to hopefully satisfy as many USGT fans as possible.
Since the LFA body release it became apparent that a 190/195mm GT body was the way to go, so that's the direction we went. However, I've also noted a bit of a down-side to that width as explained below. So many enthusiasts of this class really dig the realism factor, so in the case of the PFM-10 we intentionally made the front 1mm wider per side and the overall rear width approx 3-4mm wider for a couple reasons.
- in order to have realistic rear fender shapes (with a proper amount of "roll-under" behind the rear wheel openings) it automatically creates a potential "body-tuck" type situation (which we all hate
) By merely adding a few mm in that area we have hopefully created a better compromise between form and function.- Some GT enthusiasts like the staggered wheel look. Now it's tad easier to emulate the way real 1:1 supercars look with their wider rear wheels. Now 31mm rear wheels can be used if you so chose. (there are tons of them in the rc marketplace)
- From a performance standpoint, thin spacers can now be used to slightly space out the track width and possibly gain a bit of cornering stability.
I hope that helps you understand out logic here at PROTOform. We love this class and are currently hard at work on new USGT styles.
QUESTION: Do you think that we should do a 190mm version of the Lexus LFA? It would have a few updates to the aero package as seen in the real world but would essentially be 90% the same, just narrower.
Thanks for you input and comments! Much apprecuiated.

Dale Epp - PROTOform
After reading this I now understand the reason behind what you did and why the rear of the body is so wide. To be honest as soon as I was made aware of this it made me question what was going on.
USGT has rules for a spec tire and that spec tire is 24mm in width. The tires can be mounted on 26mm rims if wanted but they perform better on 24mm. As a result there are not very many 24mm rims with alot of offset in them. So if you are running with the spec tires on 24mm wheels then a true 190mm body is what would fit and look the best. Now that being said I have run 200mm bodies with normal 24mm rims and the performance isnt much different.
Spacing out the rear of your car will cause your car to have more steering and with the spacing being off that much it could be an issue...just an FYI
A 190mm LFA would be nice!





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