Billy Johnson Service Announcement, PS4S

[BlkGT3]

opcorn:

I'm no Billy Johnson or Stuntman, not even close, :lol: but here are my thoughts.

1. Manufacturers tend to set up cars to understeer as it is safer for 99% of the driving public.

2. Running stock 295/305 MPSS the car does understeer in both AutoX and Track usage both experience and others who have driven my car. Maybe part of this is caused by the low grip floppy sidewall MPSS.

3. I am now running 305 R-S4 square and the car still has understeer but it is noticeably less than the staggered setup.

4. IMHO the car is much more fun to drive with a square setup and that is what I am sticking with. Except for camber plates and brake fluid my car is stock.

Peter

Sponsored

 

[Hack]

One thing I've noticed and I don't know whether it's a characteristic of the tires, car or something else, but the GT350 likes more steering angle than I expected.

I've been in the car a few times with pro drivers and the car was understeering and they told me to put more steering angle in. I know I was just accepting that when I started to feel some understeer it was time to back off and not realizing that the car would turn significantly more sharply with more steering angle.

Knowing this is especially useful during autocross or on a smaller track.

 

[snaproll]

I think that Ford set up the GT350R to be as quick around a road course as possible. If a square setup would have made an improvement or been equal, Ford would have put a square setup on the car. Maybe if the R had a square setup and the GT350 didn't I could be convinced that the square setup was faster.

I don't disagree that you can maybe save money with a square setup if you get free tire mounting/dismounting and your usage burns one end of the car faster. My tire guy says what he has seen is most GT350s get about half the life from the rear tires compared to the fronts. However, for me the mounting and dismounting will cost more than the possible gains. I haven't seen outer/inner edges wearing faster based on my usage.

I have a hard time imagining R owners wanting to do additional mounting/dismounting on those CF rims.



I don't believe you. To me you're just some guy on the internet making unsubstantiated claims.

Ha. I know. I love the internet. I'm no Mario Andretti, just another dude that has built and road raced Mustangs for 13 years on a budget. My opinions come straight from track experience. Otherwise yes, mostly unsubstantiated. ;)

 

[snaproll]

opcorn:

I'm no Billy Johnson or Stuntman, not even close, :lol: but here are my thoughts.

1. Manufacturers tend to set up cars to understeer as it is safer for 99% of the driving public.

2. Running stock 295/305 MPSS the car does understeer in both AutoX and Track usage both experience and others who have driven my car. Maybe part of this is caused by the low grip floppy sidewall MPSS.

3. I am now running 305 R-S4 square and the car still has understeer but it is noticeably less than the staggered setup.

4. IMHO the car is much more fun to drive with a square setup and that is what I am sticking with. Except for camber plates and brake fluid my car is stock.

Peter

Agreed. Now it would be nice to have a consolidated list of lower cost but good wheels with the offset info, spacers, lug nuts, and good value track tires to make it easy to figure out. I think the project GR 7 spoke wheels look like the best bet I've seen so far. Seems almost like heresy around here to suggest a rotatable setup.

 

[Hack]

Ha. I know. I love the internet. I'm no Mario Andretti, just another dude that has built and road raced Mustangs for 13 years on a budget. My opinions come straight from track experience. Otherwise yes, mostly unsubstantiated. ;)

For all I know, you might be a better driver than Mario. I still believe Ford had a better reason for putting a staggered setup on the GT350 and R than just "they wanted it to understeer" as you so confidently stated. Ford employees collectively may also have more Mustang road race knowledge than you. :cheers:

 

[snaproll]

For all I know, you might be a better driver than Mario. I still believe Ford had a better reason for putting a staggered setup on the GT350 and R than just "they wanted it to understeer" as you so confidently stated. Ford employees collectively may also have more Mustang road race knowledge than you. :cheers:

All good, but I don't think it's any secret that they dial in understeer for safety, it's easier to package narrower fronts, it looks more aggressive with big rears, etc. These cars have all sorts of compromises - don't think they are optimized for track speed. I'm not going to argue physics or car dynamics, but I will go out on a limb and say guys like Billy and Dean will prefer more rubber up front than less any race day given properly sized wheels and proper fit. Carry on ...

 

[Stuntman]

Appreciate your enthusiasm but I think you are missing my point. You don't put smaller tires on the front of a pony car if you want to go fast on a road course. About the only place you will find smaller front tires is on the showroom floor. I'm not knocking your baby. I too have an R and it will see Sebring this weekend. And I will wish I had a rotatable set of track tires. And hope it doesn't rain. :cheers:

I'm pretty sure most global professional GT and prototype racecars run staggered tires...

1. Manufacturers tend to set up cars to understeer as it is safer for 99% of the driving public.

Peter

Sounds like you've never driven a stock S2000, Elise/exige, MR2, C7 Z51, Z06, Viper, modern Ferrari, McLaren, any Porsche, any ///M car.(except an E46 on corner entry), etc... They all oversteer AND have staggered tires. With poor driving (turning into a corner on throttle -which hpde instructors teach) any car can understeer.

 

[bellwilliam]

edit.

 

[snaproll]

I'm pretty sure most global professional GT and prototype racecars run staggered tires...


Sounds like you've never driven a stock S2000, Elise/exige, MR2, C7 Z51, Z06, Viper, modern Ferrari, McLaren, any Porsche, any ///M car.(except an E46 on corner entry), etc... They all oversteer AND have staggered tires. With poor driving (turning into a corner on throttle -which hpde instructors teach) any car can understeer.

Oh boy. Are you an HPDE instructor or did mom just let you on the internet again?

Sounds like you should study up on weight distribution. Mustangs aren't prototypes nor 911's. And I've owned an S2000, a 911GT3, oh nevermind.

 

[Stuntman]

Oh boy. Are you an HPDE instructor or did mom just let you on the internet again?

Sounds like you should study up on weight distribution. Mustangs aren't prototypes nor 911's. And I've owned an S2000, a 911GT3, oh nevermind.

?

Your original statement was you only see staggered tires "on the showroom floor"; likely implying that all the cool track kids run square setups. I gave you an example of Prototypes and GT cars like the M3, Mustang, and Camaro (which are front-weight biased) that raced in the Gran-Am Rolex series are examples of pro racecars that run staggered tires.

What do I need to learnz about weight distribution? As far as the comment that wasn't directed to you: off the top of my head cars with shitty weight distribution that oversteer and have staggered tires: 350Z, 370Z, ZL1 Camaro.

 

[BlkGT3]

I'm pretty sure most global professional GT and prototype racecars run staggered tires...


Sounds like you've never driven a stock S2000, Elise/exige, MR2, C7 Z51, Z06, Viper, modern Ferrari, McLaren, any Porsche, any ///M car.(except an E46 on corner entry), etc... They all oversteer AND have staggered tires. With poor driving (turning into a corner on throttle -which hpde instructors teach) any car can understeer.

E36M3, E46M3, S2000, Boss 302, 2 6GT3's, 6GT2, Cayman GTS all tracked. Managed to stay away from the Gold Chain Vette crowd so far. Porsche's have most of the weight on the rear so smaller fronts work. Yes with enough power any car can oversteer but that isn't the fastest way around the track or AutoX.

Haven't had the luck of having a DE instructor telling me to be on throttle on turn in. Trail brake yes.

I do not buy into the street car manufacturer sets the cars up for track with the exception of the Porsche GT cars.

Peter

 

[Stuntman]

E36M3, E46M3, S2000, Boss 302, 2 6GT3's, 6GT2, Cayman GTS all tracked. Managed to stay away from the Gold Chain Vette crowd so far. Porsche's have most of the weight on the rear so smaller fronts work. Yes with enough power any car can oversteer but that isn't the fastest way around the track or AutoX.

Haven't had the luck of having a DE instructor telling me to be on throttle on turn in. Trail brake yes.

I do not buy into the street car manufacturer sets the cars up for track with the exception of the Porsche GT cars.

Peter

GM performance products, Porsches, Vipers, S2000s all rotate VERY well off throttle (easily oversteer) and when trail braking. BMWs tend to be hit and miss with the E30, E9X, & F8Xs being far more neutral and rotate on entry than E36 & 46s.

That's good to hear because most instructors do, because it's safe and slow.

Oh really? You definitely are a Porsche snob. Then how do you explain the extremely track capable and focused: S2000, NSX, C7 Z51, Z28, ZL1 1LE, Viper ACR, GT350R, Elise, Ferraris, McLarens, ok I don't care now...

 

[FogcitySF]

Exactly the GT3 and GT4 as well as numerous other race classes run staggered. Staggered setups in the hands of a pro driver are faster. As far as most on this forum, it won't matter either way in terms of speed, so as a practical matter running squared is simpler/cheaper.

I'm pretty sure most global professional GT and prototype racecars run staggered tires...

 

[Stuntman]

Exactly the GT3 and GT4 as well as numerous other race classes run staggered. Staggered setups in the hands of a pro driver are faster. As far as most on this forum, it won't matter either way in terms of speed, so as a practical matter running squared is simpler/cheaper.

Square setup is cheaper to run and rotate tires. This is the key, in addition to reducing understeer. In reality you can make pretty much any square or staggered setup work on a given car by setting it up accordingly with springs and bars, but for your average Joe trackday guy, running square tires is cheaper, reduces understeer, so it must be better and nothing else will work! :headbonk:

 

[TheKosherStogie]

Hey guys take it easy. I've always run square setups on my bmw's. But stuntman knows his stuff pretty well and has helped me out with my setups on other cars as well. Keep an open mind. We're all here to help each other.

Sponsored