Got a track related question? I'll try to answer.

[Joe-G]

This might be dumb, but I just picked up a staggered set of wheels.

F 17x7 +44
R 17x8 +34

Is there any disadvantage to running a square 225/45 or 235/45 on this setup?

Or, is there a big no no to running the 7j in the back, and the 8j in the front for better steering response?

Would this hinder performance? What would you recommend? Sell it?

[Northwest86]

Understeer. Don't see why you couldn't put the larger set on the front though.

[Apex_BRZ]

Visiting Road America in April. The car is ready, except for brake pads. Last year, I used Carbotech XP8 rear and XP10 front. The car has ducting, titanium shims, DBA T3 rotors, and RBF600 fluid. The tires are Bridgestone RE-71R.

At the last event at RA, I had added the titanium shims. After that addition, it appeared the heat stayed in the pads and the front pads were overheating and smearing on the rotors. At the time when I asked about it, you recommended to use a square pad setup. I'm going to do that now before RA again.

However...along with the square pad setup, could it hurt anything to move up to XP12's?


--------------------------------
During some searching, I came across this from a vendor regarding a BRZ and XP12:

"XP12's can be used for track days but the higher heat they generate can work the stock rotors pretty hard. If you need XP12's, you also need to bleed your brakes after every event and brake ducts. Flush the brakes after every 4 track days."

[ajc209]

Fuel Starvation.

Now I know there are few threads and comments on this, but I hope some people here with a lot of track experience and have seen a lot of track frs/brz might be able to help me out.

Has anyone seen the fuel starvation issue with high performance street legal tyres at the track? Namely the AD08R.

I've got FI ~250WHP on pump gas and Ohlins coilovers. Not had an issue on the stock wheels but I will soon be fitting 18x9 rims and was looking at the AD08R 255/35 (their recommended width for a 9 inch rim).

I've read an uprated pump helps but i've also read the opposite. Has anyone experience the issue, then fitted an uprated pump to prove it does actually help the issue?

Thanks

[ka-t_240]

Originally Posted by ajc209

Fuel Starvation.

Now I know there are few threads and comments on this, but I hope some people here with a lot of track experience and have seen a lot of track frs/brz might be able to help me out.

Has anyone seen the fuel starvation issue with high performance street legal tyres at the track? Namely the AD08R.

I've got FI ~250WHP on pump gas and Ohlins coilovers. Not had an issue on the stock wheels but I will soon be fitting 18x9 rims and was looking at the AD08R 255/35 (their recommended width for a 9 inch rim).

I've read an uprated pump helps but i've also read the opposite. Has anyone experience the issue, then fitted an uprated pump to prove it does actually help the issue?

Thanks

I've had issues at around 1/3 tank, maybe a bit more, after a hard left with a down hill which was followed by a hard accell straight. Other than that, I have ran the car on other strucks to under 1/4 with out issues.

[ajc209]

Originally Posted by ka-t_240

I've had issues at around 1/3 tank, maybe a bit more, after a hard left with a down hill which was followed by a hard accell straight. Other than that, I have ran the car on other strucks to under 1/4 with out issues.

What is the spec of your car?

From what I understand force induction and high cornering g's are the cause.

So the more the power the worse it is and the more cornering grip the worse it is?

[ScionOfHorus]

@the_slow_one will fuel starve even he's under 1/2 tank N/A. E85 though.

Sent from my MotoE2(4G-LTE) using Tapatalk

[ka-t_240]

Originally Posted by ajc209

What is the spec of your car?

From what I understand force induction and high cornering g's are the cause.

So the more the power the worse it is and the more cornering grip the worse it is?

More power = more fuel needed, so yes that can impact.
More grip = more fuel sloshing around in the tank(at least in my eyes).

I've seen a number of other people comment on the left hand turns having some fuel issues.

My car is an E85 NA car, full suspension on re71r. Uses about the same amount of fuel as my buddies supercharged car.

[ajc209]

Originally Posted by ka-t_240

More power = more fuel needed, so yes that can impact.
More grip = more fuel sloshing around in the tank(at least in my eyes).

I've seen a number of other people comment on the left hand turns having some fuel issues.

My car is an E85 NA car, full suspension on re71r. Uses about the same amount of fuel as my buddies supercharged car.

We cant get those in the UK but I ahve heard they are not far off R comps? How'd they compare to the AD08R?

[Lynxis]

Originally Posted by ajc209

What spec of car are you?

From what I understand force induction and high cornering g's are the cause.

So the more the power the worse it is and the more cornering grip the worse it is?

It's been my understanding that the fuel cut only affects people on E85 while taking a long, sustained left hand sweeper with high gs. It shouldn't be an issue for you if you're on pump gas or if you go on tracks without a long left hand sweeper.

[Chico]

Originally Posted by ajc209

Fuel Starvation.

Now I know there are few threads and comments on this, but I hope some people here with a lot of track experience and have seen a lot of track frs/brz might be able to help me out.

Has anyone seen the fuel starvation issue with high performance street legal tyres at the track? Namely the AD08R.

I've got FI ~250WHP on pump gas and Ohlins coilovers. Not had an issue on the stock wheels but I will soon be fitting 18x9 rims and was looking at the AD08R 255/35 (their recommended width for a 9 inch rim).

I've read an uprated pump helps but i've also read the opposite. Has anyone experience the issue, then fitted an uprated pump to prove it does actually help the issue?

Thanks

I have this exact problem at the track. last year was the first year I swapped tires (AD08Rs - 245/40) from the original spec and I'm running an E85 NA tune.

On the two long, fast left handers I get fuel cut off and it's enough of a jolt to unbalance the car. Not the best feeling when you're not expecting it, lol. Both times I'm guessing my fuel level was just over 1/4. My "fix" this year is to try and keep the level above half to see if that helps. Otherwise it might be back to 94.

[CSG Mike]

Originally Posted by Apex_BRZ

Visiting Road America in April. The car is ready, except for brake pads. Last year, I used Carbotech XP8 rear and XP10 front. The car has ducting, titanium shims, DBA T3 rotors, and RBF600 fluid. The tires are Bridgestone RE-71R.

At the last event at RA, I had added the titanium shims. After that addition, it appeared the heat stayed in the pads and the front pads were overheating and smearing on the rotors. At the time when I asked about it, you recommended to use a square pad setup. I'm going to do that now before RA again.

However...along with the square pad setup, could it hurt anything to move up to XP12's?


--------------------------------
During some searching, I came across this from a vendor regarding a BRZ and XP12:

"XP12's can be used for track days but the higher heat they generate can work the stock rotors pretty hard. If you need XP12's, you also need to bleed your brakes after every event and brake ducts. Flush the brakes after every 4 track days."

Sounds like very generic information. Bleeding is completely dependent on each individual person's use. Rotor wear is the same.


The only thing you'd hurt by going to the XP12, is possibly overbraking yourself, but it's better to have too much pad, than not enough, as you've already learned.

With an advanced driver, you can still not have enough pad with the XP12. If you find yourself at that point, the real solution is a BBK.

The RE71R is a really, REALLY sticky tire, so it's easy to overheat the brakes, as you're stopping harder and faster with those tires.

[CSG Mike]

Originally Posted by ajc209

Fuel Starvation.

Now I know there are few threads and comments on this, but I hope some people here with a lot of track experience and have seen a lot of track frs/brz might be able to help me out.

Has anyone seen the fuel starvation issue with high performance street legal tyres at the track? Namely the AD08R.

I've got FI ~250WHP on pump gas and Ohlins coilovers. Not had an issue on the stock wheels but I will soon be fitting 18x9 rims and was looking at the AD08R 255/35 (their recommended width for a 9 inch rim).

I've read an uprated pump helps but i've also read the opposite. Has anyone experience the issue, then fitted an uprated pump to prove it does actually help the issue?

Thanks

It's highly situational, but without long left sweepers or banked lefts, you shouldn't have issues, unless you're under 1/3 of a tank on gasoline. The overall fuel volume demand of your car is less than that of a NA car on E85.

[ajc209]

Thanks for your responses guys.

I usually go through a tank in the am session and refill at lunch before using another tank in the pm session. It looks like a 25l fuel container for trackdays might be a good idea so I can keep it topped up.