Anyone recall the issues with APR-Tuned (aka 1st Generation Stoptech ST-40) Calipers ?
06-10-2005, 01:03 PM
#1
Anyone recall the issues with APR-Tuned (aka 1st Generation Stoptech ST-40) Calipers ?
I came across a cheap set of APR 332 BBK and was trying to recall what were the problems with Gen1 ST Calipers, or improvements in Gen2 that drove the changeover?
06-10-2005, 01:55 PM
#5
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When you were speaking to them and asked "why", what did they say?
If you were neither *speaking* with them, nor *asked why*, I'd probably try that first.
I believe they changed piston sizes at one point, but I'm not 100% and if they did, I don't know when.
I believe they changed piston sizes at one point, but I'm not 100% and if they did, I don't know when.
06-10-2005, 02:09 PM
#6
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The original ones were not painted on top of the powdercoat, which would eventually flake off...
Bob at Stoptech (Torrance, CA) has said they'll refinish them for a nominal fee. Keep in mind also, that the APR versions did not include the rotors with directional hats. Beyond the finish, the calipers themselves are identical. (Orignially, Stoptech used a different cylinder bore as well, but they eventually realized that APR's bore spec was a better fit, and began using that spec for the "in house" ST-40s as well.)
-Michael.
-Michael.
06-10-2005, 02:16 PM
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Per the ECS tuning brake bias table, the 1st gen Stoptech calipers had smaller pistons.
<ul><li><a href="http://www.ecstuning.com/stage/images/product/brakes/ECS-Stage3v1/Caliper-Piston-Sizing-S4.pdf">ECS Brake Bias Chart</a></li></ul>
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06-10-2005, 03:18 PM
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I have APR StgIII brakes. They may have been repainted, but I really like the finish.
Sort of a flat black that doesn't need to be washed all the time and goes nicely with brake dust 
They pull me down from big speeds easily and always have more braking force in reserve.
I have had problems with the pad backing plate rubbing against the hat when the brake pad is worn down enough. Now I grind a little off the pad's backing plate where it would normally touch the hat, but I have been replacing the pads before they even get to that point.
They pull me down from big speeds easily and always have more braking force in reserve.
I have had problems with the pad backing plate rubbing against the hat when the brake pad is worn down enough. Now I grind a little off the pad's backing plate where it would normally touch the hat, but I have been replacing the pads before they even get to that point.
06-10-2005, 04:18 PM
#10
AudiWorld Super User
iirc, they changed the piston sizing within the production of their "1st gen caliper"
for the S4.
2nd gen has a change to how the brake pads are held in so that bolt isn't accessed from the rear of the caliper.
could be wrong. that's what i remember.
2nd gen has a change to how the brake pads are held in so that bolt isn't accessed from the rear of the caliper.
could be wrong. that's what i remember.