Autocross tire thoughts, Here's something for you to ponder Options

[PeeGreen 914]

So speaking with Jeff K last night we were talking about tires. I mentioned what my plans were and talked a little about contigencies. I asked what his thought were on tires for prepared classes. This is direct from him

In my experience, the Goodyear is the fastest tire out there. The Avon is second and Hoosier is third. I use to be a contract driver with Hoosier but after doing much testing I found Goodyear to be better and willing to do what it takes to change.

So for my class I will be going with Goodyear.

What are your thoughts on this?

[Borderline]

I'm going to follow Trekkor's lead and try running some 13" wheels. Where I AX (Marina, Ca near Monterey) it is always cold. I can never get any real heat into the tires. the 13" wheels will make some soft compound tires available. They will also weigh less and used tires are available cheap. FWIW

[Solo914]

I'm going to follow Trekkor's lead and try running some 13" wheels. Where I AX (Marina, Ca near Monterey) it is always cold. I can never get any real heat into the tires. the 13" wheels will make some soft compound tires available. They will also weigh less and used tires are available cheap. FWIW

Maybe this has already been covered, but I was thinking the same thing but was told 13s don't fit over stock brakes. What does it take to make them fit?

[Borderline]

I'm going to follow Trekkor's lead and try running some 13" wheels. Where I AX (Marina, Ca near Monterey) it is always cold. I can never get any real heat into the tires. the 13" wheels will make some soft compound tires available. They will also weigh less and used tires are available cheap. FWIW

Maybe this has already been covered, but I was thinking the same thing but was told 13s don't fit over stock brakes. What does it take to make them fit?

Trekkor has more experience than I do. I think he has found some Audi/VW Fox calipers that will bolt on the front and clear ok. The rears are very very close. I think some minor grinding on the outside of the caliper...very carefully will do it.

On the fronts, I'm going to do a little extra. My car is pretty much a dedicated AX car that is still streetable. With the 15" wheels I have raised the spindle on the strut to lower the car and still maintain suspension geometry. So as it sits, there is no way I can put 13" wheel on the front. So my plan is to lower the spindle on the strut, machine the rotor to accept a light wt Wilwood caliper, and weld up some mounting tabs for the Wilwood caliper. The 13" tires weigh about 10#. the Wilwood caliper weighs less than 2#. The radical machining on the rotor will save about 3#. The 13" wheels in steel will weigh about 3# less than my 7" revolutions. That's about 20# savings on each front corner. With some savings on the rear, I expect a total wt reduction of about 60#!! That is all unsprung wt and some rotating mass! The Goodyears are available in 165 compound in the 13" size so I'm hoping for a little extra grip and some faster times. All the above number are based on the narrow 13" tires so they will fit under my narrow body fenders. Big plans little budget hehehe

[ConeDodger]

I'm going to follow Trekkor's lead and try running some 13" wheels. Where I AX (Marina, Ca near Monterey) it is always cold. I can never get any real heat into the tires. the 13" wheels will make some soft compound tires available. They will also weigh less and used tires are available cheap. FWIW

Maybe this has already been covered, but I was thinking the same thing but was told 13s don't fit over stock brakes. What does it take to make them fit?

Trekkor has more experience than I do. I think he has found some Audi/VW Fox calipers that will bolt on the front and clear ok. The rears are very very close. I think some minor grinding on the outside of the caliper...very carefully will do it.

On the fronts, I'm going to do a little extra. My car is pretty much a dedicated AX car that is still streetable. With the 15" wheels I have raised the spindle on the strut to lower the car and still maintain suspension geometry. So as it sits, there is no way I can put 13" wheel on the front. So my plan is to lower the spindle on the strut, machine the rotor to accept a light wt Wilwood caliper, and weld up some mounting tabs for the Wilwood caliper. The 13" tires weigh about 10#. the Wilwood caliper weighs less than 2#. The radical machining on the rotor will save about 3#. The 13" wheels in steel will weigh about 3# less than my 7" revolutions. That's about 20# savings on each front corner. With some savings on the rear, I expect a total wt reduction of about 60#!! That is all unsprung wt and some rotating mass! The Goodyears are available in 165 compound in the 13" size so I'm hoping for a little extra grip and some faster times. All the above number are based on the narrow 13" tires so they will fit under my narrow body fenders. Big plans little budget hehehe

Not to mention the instant gearing change giving you big grunt out of corners. I went to 15" Cookies and Victoracers this year from 16" Fuchs and the car really scoots out of corners. Love it!

[grantsfo]

I'm going to follow Trekkor's lead and try running some 13" wheels. Where I AX (Marina, Ca near Monterey) it is always cold. I can never get any real heat into the tires. the 13" wheels will make some soft compound tires available. They will also weigh less and used tires are available cheap. FWIW

Maybe this has already been covered, but I was thinking the same thing but was told 13s don't fit over stock brakes. What does it take to make them fit?

Trekkor has more experience than I do. I think he has found some Audi/VW Fox calipers that will bolt on the front and clear ok. The rears are very very close. I think some minor grinding on the outside of the caliper...very carefully will do it.

On the fronts, I'm going to do a little extra. My car is pretty much a dedicated AX car that is still streetable. With the 15" wheels I have raised the spindle on the strut to lower the car and still maintain suspension geometry. So as it sits, there is no way I can put 13" wheel on the front. So my plan is to lower the spindle on the strut, machine the rotor to accept a light wt Wilwood caliper, and weld up some mounting tabs for the Wilwood caliper. The 13" tires weigh about 10#. the Wilwood caliper weighs less than 2#. The radical machining on the rotor will save about 3#. The 13" wheels in steel will weigh about 3# less than my 7" revolutions. That's about 20# savings on each front corner. With some savings on the rear, I expect a total wt reduction of about 60#!! That is all unsprung wt and some rotating mass! The Goodyears are available in 165 compound in the 13" size so I'm hoping for a little extra grip and some faster times. All the above number are based on the narrow 13" tires so they will fit under my narrow body fenders. Big plans little budget hehehe

Not to mention the instant gearing change giving you big grunt out of corners. I went to 15" Cookies and Victoracers this year from 16" Fuchs and the car really scoots out of corners. Love it!

Its probably going to be a disadvantage on gearing if he stays with stock gearing with a big torquey motor. I'd be looking for a taller 2nd gear. The torque gain just from smaller tires will be more than enough to offset taller gear. What would top speed in 2nd and 3rd be on the 13's?

I'm a true believer in tall gearing for AX after driving my Boxster on tall gears. Even the best shifters are losing time when they shift.

Bill, You would have a TTOD car locally if you put wide 13 inch 165 good years or 25 B Hoosiers on your car. Are you going to put fenders on your car? (IMG:style_emoticons/default/welder.gif)

[Borderline]

I'm going to follow Trekkor's lead and try running some 13" wheels. Where I AX (Marina, Ca near Monterey) it is always cold. I can never get any real heat into the tires. the 13" wheels will make some soft compound tires available. They will also weigh less and used tires are available cheap. FWIW

Maybe this has already been covered, but I was thinking the same thing but was told 13s don't fit over stock brakes. What does it take to make them fit?

Trekkor has more experience than I do. I think he has found some Audi/VW Fox calipers that will bolt on the front and clear ok. The rears are very very close. I think some minor grinding on the outside of the caliper...very carefully will do it.

On the fronts, I'm going to do a little extra. My car is pretty much a dedicated AX car that is still streetable. With the 15" wheels I have raised the spindle on the strut to lower the car and still maintain suspension geometry. So as it sits, there is no way I can put 13" wheel on the front. So my plan is to lower the spindle on the strut, machine the rotor to accept a light wt Wilwood caliper, and weld up some mounting tabs for the Wilwood caliper. The 13" tires weigh about 10#. the Wilwood caliper weighs less than 2#. The radical machining on the rotor will save about 3#. The 13" wheels in steel will weigh about 3# less than my 7" revolutions. That's about 20# savings on each front corner. With some savings on the rear, I expect a total wt reduction of about 60#!! That is all unsprung wt and some rotating mass! The Goodyears are available in 165 compound in the 13" size so I'm hoping for a little extra grip and some faster times. All the above number are based on the narrow 13" tires so they will fit under my narrow body fenders. Big plans little budget hehehe

Not to mention the instant gearing change giving you big grunt out of corners. I went to 15" Cookies and Victoracers this year from 16" Fuchs and the car really scoots out of corners. Love it!

Its probably going to be a disadvantage on gearing if he stays with stock gearing with a big torquey motor. I'd be looking for a taller 2nd gear. The torque gain just from smaller tires will be more than enough to offset taller gear. What would top speed in 2nd and 3rd be on the 13's?

I'm a true believer in tall gearing for AX after driving my Boxster on tall gears. Even the best shifters are losing time when they shift.

Bill, You would have a TTOD car locally if you put wide 13 inch 165 good years or 25 B Hoosiers on your car. Are you going to put fenders on your car? (IMG:style_emoticons/default/welder.gif)

The plan is still to keep it a narrow body. I'm running a flipped 5th for 3rd gear. At 7K I should hit about 68 mph in 3rd. 2nd gear should be good for almost 50 mph. I'll probably still do a fair amount of shifting. The car should be really quick in the slow tight stuff.