Mk60e5 ABS

[hoveringuy]

As a public service, there's now a signal converter that will let you use your stock e30 sensors and rings with the E5. It's pretty slick...

https://happycactusgarage.com/products/mk60-companion

[Digitalwave]

This is another good MK60 resource on Facebook: https://www.facebook.com/groups/1056638784424876

[hoveringuy]

I've been having issues with my FL brake dragging when it gets hot, at first I thought it was lack of slack in my linkage and the MC wasn't venting fluid, but yesterday it was happening consistently almost exactly 10 minutes into each session.

I *think* it was caused by one of the pads being too tight between the upper and lower bridges, like the steel backer was expanding with heat and jamming the pad. It was very difficult to pull out.

[R3VM3UP]

Great information here. I plan to try something similar but I’ve been eyeing an S197 mustang ABS swap since there is a readily available race version available. I already have a stock S197 ABS that I have confirmed works with MK60 sensors, I have not installed it yet though but I may try it before springing for the race version.

What master cylinder and caliper piston sizes are you running? I currently have the same booster delete setup from Massive with 5/8” masters and 1.62” front and 1.25” rear superlite calipers.

[hoveringuy]

What master cylinder and caliper piston sizes are you running? I currently have the same booster delete setup from Massive with 5/8” masters and 1.62” front and 1.25” rear superlite calipers.

5/8"?

I run 3/4" MC front/rear and the same calipers. 1 5/8" front and 1 1/4" rear.

I tried running slightly smaller 0.7" MC's but even that made me feel like I was running out of pedal and required a brake zone pre-pump. If I don't switch the pads inboard-outboard every 3-4 events I get enough pad taper in the front that it feels like pad knock-back, and larger MC's are much more tolerant but still have good effort and feel.

[R3VM3UP]

That is surprising to hear, my pedal is very firm with minimal travel on this setup. I was actually contemplating going to a slightly larger front caliper to reduce pedal efforts further. Not that it really needs it but it would make it more pleasant to drive on the street. I have the lever arm on the pedal box set to the position with less leverage. I’m using Tilton master cylinders and all soft lines are replaced with braided stainless. Pads are Ferrodo DS2500. Are you certain you don’t have air trapped somewhere?

[hoveringuy]

. Are you certain you don’t have air trapped somewhere?

It sure felt like it, but for the most part it was resolved by swapping the pads inboard-outboard. Somehow the taper created a knockback. The Mk60 has a really good bleed program so I know there's zero air.

I also discovered during overhaul of the front brakes that Wilwood rotors suck, they were getting radial cracks all the way around at each mounting boss after 4 events. I stick with Hawk from now on but they were unavailable for a while.

With the new pads, cleaned pistons and fresh seals I could probably get away with smaller MC's but I'm just used to how it feels now. Also switching to PFC-11 in the front instead of PFC-08 (still PFC-08 in the rear...) so I'm curious how that will feel.

[R3VM3UP]

Which leverage setting is your box on? Did you notice this with brand new pads or only after they started to taper? I’ve only done a few miles of street driving so I can’t speak on pad taper with my setup, but my pedal has very minimal travel before getting very firm. It’s probably like 1/8 or less of the theoretical pedal travel.

[hoveringuy]

I'm not sure I have two settings..?

I will say that with new pads and rotors the brake pedal is much firmer and more consistent, zero slop developing like before. It probably would work with smaller MC's right now

I'll need to be more vigilant in keeping the pads square as they get worn, it seems to create that "air" feeling.

[hoveringuy]

also, the Wiwood rep told me that the pad steel backers are stamped and can be off the spec.

Our shape is supposed to be 4.75" and I measured a few that were a few hundredths more. Filing the ends smooth and to spec made them slide in and back & forth like 'butta.

[R3VM3UP]

I purchased my booster delete bracket from Lee in 2018 so it’s possible the design has changed. On mine there are two different points where the pedal linkage can attach to the lever that pushes on the masters. One provides a 6:1 pedal ratio and the other provides a 7:1 ratio. I chose 6:1 since that’s what most pedal boxes use.

Anyhow, good info here. I’ll have to get some mileage on mine and see how things develop. The largest option of the wilwood superlite actually has 1.87 and 1.75 pistons to help reduce taper. If I end up changing around caliper and master sizes again that’s probably what I’ll go for. Thanks for the tip on filing the pads for smooth fitment. My ferrodo pads seemed to fit without issues but I had been considering going to a PFC11 up front for more bite. How do you like them?

[hoveringuy]

I had been considering going to a PFC11 up front for more bite. How do you like them?

Just driving around the street all I can say is "they work". I'll be down at the Ridge the 18th for a proper evaluation, I didn't think the PFC-08 had enough bite up front.