Suspension Advice Needed, Front bars, shocks and rear springs. Options

[jmill]

Building a Street/Track car, think more track than street. The car is flared with 16x7's and 16x8's. Building a 2.4 6 with 2.2S p/c's and 911 front suspension. I need some advice on front torsion bar size, rear springs, inserts/shocks, and sway bar size. Thanks. (IMG:style_emoticons/default/beer.gif)

And what do you guys think about these?

[brant]

JP,

not arguing
but now I'm curious
I get a ton of rear brake wear/heat
never enough to want to go back to my old cars vented rear rotors... never a problem.

but I'm wearing through rear brake pads 2 to 1 over the front
same compound front and rear

fronts are vented with S calipers (knock backs gutted)
rears are 914 front early calipers moved to the back (same pad as a M caliper)

I think the 914/4 front may have a tiny bit smaller piston than a true 911 front M caliper (even though the pad size is the same)

maybe its the 1-2mm smaller piston?

I've fabricated all new rear brake lines, but I think they were of stock diameter.

I'm running an adjustable proportioning valve (that I dare not open all of the way)

our engine weights were similar, although your car weight may have been a bit less than mine.

still I would say similiar chassis.... yet I'm buring through 2 sets of rear pads to ever front and getting tons of rear brake.

maybe heat?... maybe pad compound that is working in the heat I'm getting? I dunno... but I have AMPLE rear brakes and have to dial them off a bit

I change my brake proportioning bias about once a weekend to accomodate warm, cold, or wet track

now I'm curious

[J P Stein]

JP,

not arguing
but now I'm curious
I get a ton of rear brake wear/heat
never enough to want to go back to my old cars vented rear rotors... never a problem.

but I'm wearing through rear brake pads 2 to 1 over the front
same compound front and rear

fronts are vented with S calipers (knock backs gutted)
rears are 914 front early calipers moved to the back (same pad as a M caliper)

I think the 914/4 front may have a tiny bit smaller piston than a true 911 front M caliper (even though the pad size is the same)

maybe its the 1-2mm smaller piston?

I've fabricated all new rear brake lines, but I think they were of stock diameter.

I'm running an adjustable proportioning valve (that I dare not open all of the way)

our engine weights were similar, although your car weight may have been a bit less than mine.

still I would say similiar chassis.... yet I'm buring through 2 sets of rear pads to ever front and getting tons of rear brake.

maybe heat?... maybe pad compound that is working in the heat I'm getting? I dunno... but I have AMPLE rear brakes and have to dial them off a bit

I change my brake proportioning bias about once a weekend to accomodate warm, cold, or wet track

now I'm curious

I'm no expert ( no real racin' here) but have an opinion. (IMG:style_emoticons/default/biggrin.gif)
I think you've nailed it with the word "heat".
It is not for nothing that vented rotors are the choice for racers. Heat is a killer.
It is not just the venting but also the size of the "heat sink". If you don't want to go vented rears you should start looking for some ducting to cool the rears......tho I doubt they would work very well with solid rotors. You could also use more heat resistant pad in back....an iffy proposition till everything gets up to temp.
Personally, I'd go to vented rotors, eat the weight penalty, & be done with it.

[brant]

I'm no expert ( no real racin' here) but have an opinion. (IMG:style_emoticons/default/biggrin.gif)
I think you've nailed it with the word "heat".
It is not for nothing that vented rotors are the choice for racers. Heat is a killer.
It is not just the venting but also the size of the "heat sink". If you don't want to go vented rears you should start looking for some ducting to cool the rears......tho I doubt they would work very well with solid rotors. You could also use more heat resistant pad in back....an iffy proposition till everything gets up to temp.
Personally, I'd go to vented rotors, eat the weight penalty, & be done with it.

Actually I'm not having any problems with it, No need to change to the heavy vented rear rotors
- I have all of the rear brake I can use in balance with my front S calipers
- my pad life is still about 10 full track days, so pad life is not a concern for me
- I never over heat the rear brakes.... (or fronts for that matter)

the only reason I brought it up was that Ive heard multiple people claim they don't have enough rear brake even with the proportioning valve fully open...
yet I have plenty... I can open the valve further and lock the rears first at will
so I'm just curious what is different in the set ups to make mine well balanced?

no need to change anything on mine... I've got what I want and what others can't seam to achieve.

I used to have vented rear rotors on a different teener race car
maybe if I had another 100hp I'd feel differently (although I doubt it)
but I don't need them... can't see adding the weight back if it only makes you heavier-slower....

besides. These are momentum cars. If you are heating your brakes too much with 200hp, you are just braking too much. I've known faster guys than I in teeners that have even smaller brakes without problem... they just don't brake much and they are faster for it.

actually the fastest real racers I know don't use vented. On the race tracks (don't know autox) if you talk to some of the true 914 drivers (such as Allen Johnson in a 205hp 4-cylinder) They will run laptimes faster than the 500hp mustangs, corvette's and camaro's and do it all without big brakes. You can't run those kind of lap times if your braking much.

brant