Caliper location, adapters, and rotor hats??

[TehRaydarlover]

So I'm trying to work out my brakes... and could use some advice

Things I'm trying to decide on:
- How far away the caliper should be from the wheel. Leave more room for different wheel options?
- How far can I move the caliper before the rotor hat and adapter bracket offset is enough to cause an undesirable torque during braking?
- Do I even need to be worried about this torque?

The two calipers I have modeled are the Wilwood Forged SL6R (left) and the Wilwood Forged Narrow SL6R (right)

The narrow version is about $75 more a corner, not sure if its worth the price difference, but if the offsets and clearance are an issue the narrow version should be better.

Any help would be greatly appreciated!! :)

[Northern]

With the Forged SL6R (Left) I'd be concerned about balljoint clearance.

I'm concerned/curious about other tradeoffs that come with the Narrow calipers, rigidity being the first thing that comes to mind.

From what I've seen, most rotor hat setups seem to look more like the Right/Narrow one.

[Northern]

Also, are you planning on .81" thickness or 1.25" up front? I think the thicker one is worth it for the minimal increase in mass/cost.

[TehRaydarlover]

I think both would clear the ball joint but it would probably be a good idea to have the caliper in my hands before I make the adapter. I'm thinking if there is a clearance issue I could rotate the caliper away from the ball joint with the adapter.

I know the Narrow SL6R uses a thinner pad, 0.65" vs 0.80". I'm guessing they are just designed a little better, to use less material. They have the same pad and piston area.

Yes, I was planning on using 1.25" thickness. and either the 300mm or 330mm diameter rotor.

It seems pretty common for the hats to have a pretty large offset. You can buy hats from wilwood that are made from 6160 Aluminum that have well over an inch of offset. Even our stock rear rotor has a lot of offset for the e-brake. It would probably be fine for the inch or so offset I need. What I'm more worries about is the offset on the adapter. The mounting ears to the strut housing are pretty small!

[Northern]

Sorry, I mean balljoint clearance with the disc, it's already pretty close with the stock brakes. I assume we're not keeping the dust shield either way, but it would be nice to use the dust shield bolts for a cooling duct mount.

[TehRaydarlover]

Ohh, yeah good thinking! It might be pretty close to hitting. I'll take some measurements and see what kind of room I have to work with.

Yeah defiantly not going to be able to use the stock dust shield but I might be able to fab something for a cooling duct.

[Northern]

Any price difference in the pads? I really think the thickness difference is just part of the tradeoff for narrow calipers, probably have to change them more frequently.

[TehRaydarlover]

So measuring the location of the ball joint, its 0.156" closer to the wheel than the stock caliper mount. I added it to my autocad drawing and your correct! Using the thicker SL6R caliper would mean the disk would contact the ball joint. Looks like I'll have to go for the thinner FNSL6R caliper.

I briefly looked at the cost of pads and off Wilwood's website comparing the same pad type the 0.80" and 0.65" are the same price. The prices might differ from another source but it looks like I wont have to worry with the fitment issue haha.

Thanks for all the help!! Time to break out the wallet and fire up the mill haha

[Northern]

random question... ever look at the radial mount stuff? IIRC, the wilwood radial mount bracket that converts the caliper to lug mount, conveniently at the same 3.5" spacing as the e30 front stuff. Just not sure about how it would sit offset-wise.

[TehRaydarlover]

I did, they are the same price as the more expensive FNSL6R caliper and you are limited to the 1.1" thick rotor, no difference in price for the thinner rotor either. I held off buying anything yet until I can test fit my wheels. If I have enough clearance to the fender I could make the hat about 0.375" thicker and get away with using the cheaper standard SL6R caliper. I kind of doubt I'll have room but I'll know for sure with the wheels mounted. It'd be nice if I could use the stranded SL6R caliper, same 0.80" thick pads as the rears, plus maybe a little bit stiffer.

[Northern]

I noticed the calipers you listed in your main thread were radial mounts. Was that unintentional then?

I think it would be great if there's room to fit the standard caliper over the narrows. Not a fan of paying more money for less capability haha.