club-racers and motorheads

heiney9

a_mattison wrote: »

Thanks for the conversation on these topics, by the way. I've been trying to talk about this stuff with the peeps on the G35 forum and all anybody wants to talk about is weather or not they can beat a Mustang out of the light or other worthless crap. who'd a thought I'd have to have this conversation in an audio forum.

I know it's hard for some to not have a pissing contest conversation. It's the same at the Vortex (VW/AUDI site). I just looked in their amateur racing forum and not a whole lot of discussion going on.

The G35 is a great platform and just like audio modifying a car can be a huge black hole and you end up doing things more than once or things not exactly helpful to the cause. For a course like Blackhawk and many like it suspension tuning gets far better results than all out HP. That's why there are so many Miata's up there. They aren't fast but they are hoot to drive fast.

I'm not familiar enough with the G35 platform to give you any solid advice. I'm used to FWD cars. Suspension tuning is an art so do your homework and figure out what works well for what ever result you are trying to accomplish.

I have the advantage of my VW mechanic also racing so he knows the combo's that work and the ones that don't; from modest to extreme. Plus he can install the parts properly and diagnose any problems. My Bilstein /H &R setup is about as extreme as one should go for the street(around here). It's lowered about 1 1/2" and still has some decent ride quality. Any lower and the oil pan will hit the tops of speed bumps etc.

FWIW

H9

dkg999

a_mattison wrote: »

Well...yea. I guess I don't even think in that direction. In all reality, though, what most people think is rotor warpage causing pulsation is actually pad transfer. When you bed a new set of pads into a rotor you are actually depositing pad compount into the rotor material. If your rotors get really hot and you are sitting at a stop light with the brakes on, a lot of material transfers causing a high spot on the rotor. A dead giveaway of this happening is a distinct outline of the pad on the rotor surface. See it all the time. the guys at stoptech have an article that speaks to this technically and quite clearly. I'll see if I can find it.

I actually just had this happen on my low-tech, non-performance, Honda Accord! I go from Belvidere to the Hwy 59 exit off of I-90 at about 80 mph continuous speed for 35 miles, then usually come to a dead stop on the exit ramp with hot rotors and the brakes locked. I had to have the rotors lightly turned to get the brake pad gunk off and get rid of the pulsation in the front brakes.

Lowell_M

dkg999 wrote: »

I actually just had this happen on my low-tech, non-performance, Honda Accord! I go from Belvidere to the Hwy 59 exit off of I-90 at about 80 mph continuous speed for 35 miles, then usually come to a dead stop on the exit ramp with hot rotors and the brakes locked. I had to have the rotors lightly turned to get the brake pad gunk off and get rid of the pulsation in the front brakes.

:cool:Man, its cool to say smart things that are true once in a while.:cool:

heiney9

dkg999 wrote: »

I actually just had this happen on my low-tech, non-performance, Honda Accord! I go from Belvidere to the Hwy 59 exit off of I-90 at about 80 mph continuous speed for 35 miles, then usually come to a dead stop on the exit ramp with hot rotors and the brakes locked. I had to have the rotors lightly turned to get the brake pad gunk off and get rid of the pulsation in the front brakes.

Whenever I brake hard; after I come to a complete stop I take my foot off the brake (if possible) to prevent that. I picture it like an egg sizzling in a frying pan. Obviously it's not always possible to take your foot off the brake but it is easier with manual tranny's.

Sami

heiney9 wrote: »

I assumed everyone knew I meant cast.....but thanks for clarifying

Actually most rotors are drilled. Cast rotors are major $$$$. Solid rotors provide the most stopping power BTW.

PolkThug

a_mattison wrote: »

Does anybody here have any experience adding FI to a RWD car with similar limitations in grip and have any comment on the ability of the car to get the power to the ground? I'm not interested in a drag strip setup, rather a roadcourse setup.

Lower the car.
Get a stiffer front sway bar.
Get dedicated wheels and tires for the road course.
-if you can't afford the above, get tires with a less than 200 treadwear rating.
Battery relocation to the trunk.

concealer404

Sami wrote: »

Actually most rotors are drilled. Cast rotors are major $$$$. Solid rotors provide the most stopping power BTW.

The rotors themselves aren't really what provide the stopping power, but rather, their largest part is played in heat dissapation.

Solid vs. Slotted vs. cast w/ holes vs. slotted and holed, can't really make a blanket statement as to which "provides the most stopping power" because there's way more to it than just that.

Sami

These a long answer to it, and the short answer. I just went with the short answer.

dkg999

My local truck guy back in IA tells me I need to go to thicker, better vented rotors with different pads (non-ceramic) to get the braking performance I want on my truck. When I put my track loader on my 18' trailer and have close to 10,000 lbs hooked up, the brakes just get a little non-confidence inspiring on my Silverado. He basically said that drilling and cross-slotting them wasn't going to add to braking performance and was one of those internet myths.

Joe08867

Sami your statement is correct for a single high speed stop but for repeated stops slotted or drilled would be better or at least more consistent.

Heat soak would boil the brake fluid in a solid rotor much faster than a slotted/drilled one..

That is why they use slotted/drilled in race cars.

concealer404

Joe08867 wrote: »

Sami your statement is correct for a single high speed stop but for repeated stops slotted or drilled would be better or at least more consistent.

Heat soak would boil the brake fluid in a solid rotor much faster than a slotted/drilled one..

That is why they use slotted/drilled in race cars.

It's actually for gas dispersion, but yeah.... close enough.

For a street driven car with traditional materials being used in the rotors, the only main reason to have slotted is for the dispersion, and the small guard against glazing.

Race cars' braking systems were designed to be used with those rotors, often made of ceramic. Your average production car was built with metallic rotors, and upgrading them won't do much.

Sami

Joe08867 wrote: »

Sami your statement is correct for a single high speed stop but for repeated stops slotted or drilled would be better or at least more consistent.

It is not that simple either, the answer. For street car with occasional track time, solid rotors and ducting is a very good option. Drilled rotors do not last.