Wilwood 16" kit caliper issues

[tigerdog]

Using 120-6806 calipers with the Wilwood 16" upgrade I can stop from 30mph in 22 feet 7 inches. I had three goes at it... I then tried it in my Vauxhall Zafira and came in 5 feet less with slight wheel locking.

Thanks, Paul, for these tests. With the 6806s, did you get wheel locking in any of the 3 tries? You mention it with the Vauxhall but not the Lotus. Just curious.

[paulrwebster]

No, I didn't get the wheels to lock on the 6806 tests

[Elanlover]

There's absolutely no doubt in my mind that, with the Wilwwod kit and the "mistakenly larger" pot calipers, I can now stop in a much shorter distance than with the stock setup. I haven't pulled out a tape measure to figure out by how much but there's no question its less distance not more. Also, I've yet to lock up the fronts at any speed. After talking to Bob at Hethel (and saying I haven't yet been able to lock them up) I decided to try a few hard stops as Bob suggested I may not have stomped on them as yet (which was mostly true). At 60mph and pushing them as hard as I could they wouldn't lock - not even close I suspect although the pedal travel was far more than I liked.

While I do think that the calipers Bob had at Hethel were better than the current Wilwoods we've installed (radial mount, dust seals, etc.) the main problem I want to deal with is the pedal travel. I think this has the potential to become even more of an issue if we ever come up with a slightly larger rear caliper upgrade which I think we desperately need as the Dormans are gone and they were only a slightly better version of an inferior caliper. I'm ok with the current calipers although ones with dust seals are appealing if they can be made to fit with the current hat plus rotor setup I've spent money on from Brian. Bob has asked me to take some measurements this weekend which I'll provide to him so he can determine if this is at all possible. But, i do think we need a better rear brake setup (preferably Wilwood as well to match the fronts) and I'm betting that will result in the need for a new BMC as well.

[DeeAitch]

Circa 18ft in a Nissan Note
ABS activated

[Elanlover]

Bob, just catching up on all the posts here since getting back. What were the calipers you had at Hethel and did I read correctly that you'd probably chnage the caliper to a different one now? I thought the one you had at Hethel was the Billet DynaPro Caliper with dust seals?

[RayD]

... and pushing them as hard as I could they wouldn't lock.

Which tires do you have on Blair?

Ray

[Elanlover]

Believe it or not, i still have the original OEM tires - Goodyear Eagles. Since the car I bought only had 1500 miles on it they were in pretty good shape! My 17" rims should arrive today and I'll be stickign more Goodyears on them.

[bobbrown]

Bob, just catching up on all the posts here since getting back. What were the calipers you had at Hethel and did I read correctly that you'd probably chnage the caliper to a different one now? I thought the one you had at Hethel was the Billet DynaPro Caliper with dust seals?

The calipers were Billet DynaPro Caliper with dust seals the only thing I have changed is the size to bring the upgrade inline with the Hi-spec conversion so 1.5" pistons instead of 1.38" which is also the size of all the other Wilwood upgrades with the exception of the 6816 which has 1.75" pistons
Does not sound a lot but but you have to take a square and x 4 into account.

[Elanlover]

Thanks Bob. Looking over the specs it would appear that this caliper is wider but not as "tall". My quick math tells me it will jut outboard by another 5.6 mm (just under a quarter inch) closer to the wheel face (and slightly more than that inboard). That will be close to the 16" wheel face (spokes) for sure but I'll take some measurements this weekend. On the upside, they will sit 3.8mm (just over a quarter inch) closer to the hub or further away from the barrel of the wheel. This is the area where the current Wilwood caliper is closest to the wheel so, if they don't rub the spokes we'd get more clearance against the barrel of the wheel making it easier to fit proper weights for balancing.

[bobbrown]

Thanks Bob. Looking over the specs it would appear that this caliper is wider but not as "tall". My quick math tells me it will jut outboard by another 5.6 mm (just under a quarter inch) closer to the wheel face (and slightly more than that inboard). That will be close to the 16" wheel face (spokes) for sure but I'll take some measurements this weekend. On the upside, they will sit 3.8mm (just over a quarter inch) closer to the hub or further away from the barrel of the wheel. This is the area where the current Wilwood caliper is closest to the wheel so, if they don't rub the spokes we'd get more clearance against the barrel of the wheel making it easier to fit proper weights for balancing.

That is not full picture as the single piece disc I have used allows the caliper to be moved inboard a little as I have no hat to rotor bolts to worry about
So the distance from the wheel mounting face to the disc's outboard face is 32mm, not sure what it is to the wheel spokes but I will measure it when I have it setup again.

[Elanlover]

That is not full picture as the single piece disc I have used allows the caliper to be moved inboard a little as I have no hat to rotor bolts to worry about
So the distance from the wheel mounting face to the disc's outboard face is 32mm, not sure what it is to the wheel spokes but I will measure it when I have it setup again.

Got it. I was going on the assumption (hope more likely) that we might be able to reuse Brian's hat and rotor selection when suggesting the net differences above.

[nitroman]

The calipers were Billet DynaPro Caliper with dust seals the only thing I have changed is the size to bring the upgrade inline with the Hi-spec conversion so 1.5" pistons instead of 1.38" which is also the size of all the other Wilwood upgrades with the exception of the 6816 which has 1.75" pistons
Does not sound a lot but but you have to take a square and x 4 into account.

For everyone's general information, DynaPro calipers come in a wide range of sizes. With Bob's rotor width you have five: 1.25", 1.38", 1.50", 1.62", 1.75"
However DynaLite calipers are only available in 1.38", 1.62", 1.75"

[bobbrown]

That is not full picture as the single piece disc I have used allows the caliper to be moved inboard a little as I have no hat to rotor bolts to worry about
So the distance from the wheel mounting face to the disc's outboard face is 32mm, not sure what it is to the wheel spokes but I will measure it when I have it setup again.

Got it. I was going on the assumption (hope more likely) that we might be able to reuse Brian's hat and rotor selection when suggesting the net differences above.

I have looked at it but due to the minimal clearance between the caliper and the rim I feel it is impossible
Having said that the one piece disc is cheap! and OK you do have a slight increase in weight but then you will as the disc is 4mm thicker which is always better, the thicker disc that is.

One thing I do not get with Wilwood they produce calipers and discs but do not seem to match them very well, there are very few 1" discs!

[Elanlover]

Bob, i'd be really impressed if you could figure out something like thisfor us on the rears

[L.G.]

How do you guys measure stopping distance? Go out and brake with a tape in hand?

I have a stock setup that has just been serviced and although the tires aren't in very good order I'd like to try it myself.

L.G.

[Elanlover]

FYI from Wilwood's site on drilled rotors:

Caution on drilled rotors: There is a common mis-perception that rotors are drilled to improve cooling. The reduced mass of a drilled rotor will dissipate its retained heat quicker, but it also builds up heat at a much faster rate. The decision to use drilled rotors should be solely based on the merits of the lower rotating and unsprung weight, and not for improved cooling. It is not wise to use drilled rotors in sustained high heat on hard braking tracks unless the team budget affords a high frequency of rotor and brake pad replacement.

Also, Bob, did you ever look at these Wilwood rotors for the rear? Apparently they can come undrilled to do any bolt pattern you may want.

[paulrwebster]

How do you guys measure stopping distance? Go out and brake with a tape in hand?

I have a stock setup that has just been serviced and although the tires aren't in very good order I'd like to try it myself.

L.G.

I went out with a tape measure, braked at a lamp post and marked the finishing position with a piece of chalk

[bobbrown]

Also, Bob, did you ever look at these Wilwood rotors for the rear? Apparently they can come undrilled to do any bolt pattern you may want.

I would need a solution that fits both the 15" and 16" rims, the Wilwood ones are too large

[Elanlover]

Bob, I've just taken a digital caliper to the wheels and what I've measured is that the side of th caliper (the area with the Wilwood stamp just to be clear) misses the spokes by 7mm. I could be off by a mm either way as it's hard to get in there to measure but that'd be about as much as I'd think I'd be off if at all (I think, if anything, they'd be slightly more than 7mm, not slightly less). The closest the caliper comes to the spokes is right at the top of the caliper where the spokes are curving inwards. I could not measure the distance from the "top" of the caliper to the barrel of the wheel but it looked to be about 2mm. Its very tight there. So, I think the other Wilwoods could just fit in there as they are about 5.6mm wider on the side that we see and that would potentially rub the spokes. However, I'm sure I don't need to tell you that it leaves precious little room for error. I also measured the distance from the face of the rotor to the part of the caliper that protudes ou the most and got approximately 42.5mm.

Now, I've just fitted my new 17" wheels (sans tires) and there oodles of room with these. The current Wilwood calipers are 22mm from the spokes. Guess that means I could use the existing hat and rotor and fit the DynaPro calipers you had with you at Hethel That is, provided some brillaint bloke built me a mouting kit of course. I suppose this also means i could figure out a way to fit Wilwoods on the rears - either with an hydraulic or electric e-brake setup or by using there combo caliper for the rear.

[L.G.]

I went out with a tape measure, braked at a lamp post and marked the finishing position with a piece of chalk

I'll do that as soon as it stops raining. (and probably at night)

Thanks,
L.G.