Auto-X : Big Brakes or Big Rubber?

[PrinceE30]

So, just a cool topic to discuss for Autocrossing...

What's more important in an Auto-X situation: Large brakes or wide rubber?

Rubber give more traction, but if it's too wide can you heat it up enough? Does the weight hurt you more?

I've been finding braking is SO key to good autocrossing. Braking smoothly and knowing when to let the ass out and when to just slow down some, etc...

So which is it...small wheels, wide rubber? larger wheels, large brakes, large rubber, more weight?

-Prince

[Anonymous]

I'd invest in rubber first. A good tire will improve braking, turn in, grip, and all that good stuff.

I've never find my brakes to give me fading problems. However, I would upgrade them when I felt like I was going fast enough to justify the cost.

[schnitzer teil-jäger]

AUTOCROSS...per SCCA rule book is not supposed to exceed 70mph...a good course design does not make you stand on you brakes for a 90' or better turn often.

big brakes are not needed in autocross! you will be using your money that could be spent on wheels and tires.

tires thought of the day. a little bit of hot sticky rubber is better than a lot of cold slippery rubber.

w

[e9nine]

AUTOCROSS...per SCCA rule book is not supposed to exceed 70mph...a good course design does not make you stand on you brakes for a 90' or better turn often.

hmm... interesting about the 70mph thingy...last time around at an auto-x I was definitely past 70mph when I had some fisthtailing action in 3rd gear which would explain how I spun into an excursion :twisted:

[TIATO]

For autocross, good tires are by far THE biggest bang for the buck. They will do the most to reduce run times beside seat time and smoothness

Considering the speeds attained on a autocross course, one should never expereince brake fade. If you are then you are seriously hampering your run times.

That said, BBKs are a waste of money for this application.

70mph max speed? LOL - at a divisional several years ago, in the fastest part of the course, I consistently exeeded 70mph in my IROC-Z.

[Stu]

I also say tires.

I beat a club racer in a J-stock E30 M3 in my stock 318is with only good, sticky Yoko A008RS's. They were also 185/60 on bottlecaps. Very light.

[DBurke]

Rubba all the way. Not too wide though. I know that the reason that Tunnel didn't run 275s on his e36 when it was a BSP car was the fact that they wouldn't get up to temp. His wheelspin at launch is intentional to heat tires.
Brakes, just make sure that the system is fully functional and you've got the apropriate pad for your use.