It was mentioned that the R4S Portefield is the best street and autocross brake pad. Moreover, it was hard to track down a site that sell it; now that I found one, do I order for the Benz SLK 320? The crossfire in not listed, however the calipers are the same righ? Thanks in advance! Porterfield Brake Pads - Mercedes SLK320 | R4S | AP779

 

Needswings has them. Ive used them once on autocross and they took heat well and stoped good. Les says hes melted his on a track and tried carbotech xp10 and likes those more. Thats what i will go with on my srt shortly

 

The pads at needswings are for the SRT6. So far only ones that fit the rear with an autocross ability is the disk Italias. I will have to call around tomorrow since the sites do not have the base crossfire listed.

 

From Carbotech Performance :

 

Paul, they are the same, I ordered pads for an SLK320 when I did my first swap...

 

Nice thanks

 

try a set of cool carbon pads . its what i use now

 

I did not say Porterfields R4S pads are the best for the street or autocross.

They really are a high-temp pad. Fad resistance is excellent, they are but trying to come to the first stop on a cold winter day is SCARY! With a car the weight of the Xfire, auto-x may not heat them up enough to get them into their ideal operating range.

I ran the R4S pads (not R4 pads) on a 3600 lb Supra. They fixed the problem I was having with overheating the OEM pads, but they were no good in the winter. If you don't drive in freezing climates, you'll be good to go.

I prefer the Porterfields to Hawk HPS pads though. The friction level on the HPS pads felt low. The OEM pads on a BMW Z3 had higher initial friction that he Hawk HPS. The Stoptech pads Needswings sells look interesting.

 

I am about to go with a full stoptech package on my Subie daily, I am interested to see how they will feel, everyone over there seems to like them, except the dust...

 

That's interesting about winter driving and the Poterfield. The Army sent me to Colorado Springs this time. Thanks for bringing that up. After looking at brake pads most of the day, I will try to get a matching set of the Stoptech pads that come with the big brake kit, the street performance pads. The Carbotech is too expensive, Poterfield aren't street friendly for the winter. I haven't heard good things abaut the Hawk HPS, I heard from a different forum that the Stoptech's are better. Lastly, there little information out there about the Disk Italia Hypher Ceramic. It sims easier to shop for the SRT6 than the limited when it comes to brakes
The pad is StopTech Street Performance Brake Pads (I have a guy looking for the the part number for the rear, hope they make one)
StopTech Street Performance Brake Pads are included in all Big Brake Kits besides the track-only Trophy Race Big Brake Kits. StopTech Street Performance Pads are intended for high performance street driving as well as light duty track use.

• Aggressive pad for high performance street driving
• Para-aramid composites provide linear response regardless of pad temperature
• 100% positive molded for uniform friction material density
• Low dust formulation is rotor friendly and leaves wheels cleaner
• Scorched to raise initial cold effectiveness and ease bed-in
• 100% Asbestos-free formulas

 

I finally found a good Stoptech Street Performance Pad Review: Stoptech Street Performance Pads review | Automotive Thinker - Discussing the finer points of automobiles

 

Based on the review above i got the poterfield pads for the rear. I will stick with the Stoptech for the front since it cames with the kit I ordered.

 

I'm a little late. I'm not a big fan of the Porterfield R4S. I didn't like the feel on the street or track. Yes, they work but they do neither really well. On the street, the feel was mushy IMO. At the track they were OK until I had to brake from high speed (125 to 40) then they overheated and melted. I'm a Carbotech fanboy. I loved the XP8, still have them on the rear. Moved up to the XP10 and was in love again. The make a lot of noise on the street but the pedal feel is great. Now I have XP12 on the front and I found another love. Incredible. They are expensive, they don't last forever, they don't eat the rotors, they dust like crazy, and they stop like no other pad I've ever used. For autocross, any pad will do. If your braking from high speeds constantly do yourself a favor and try at least the XP8's. Perhaps the Bobcats? Never tried them myself but based on the other Carbotech's I feel comfortable recommending you try them.

Les

 

Les has more track time than I do but I am a fan of the Porterfield R4S. I would compare them to stock pads on the street with less dust. Never had an issue with them in the cold but I am in Atlanta and we do not have bitter winters.

On the track the pads have done well. In running them at Little Talladega, Road Atlanta, and other tracks I never had an issue with the pads over heating and I had lap after lap of slowing from ~145-150 down to 35-40 and no issues with the pads. The stock rotors did overheat and I did get some shuddering.