rikhek

For road course usage in my C6 Z06 I have issues with: 1) padlets; 2) the cost of one piece race pads and padlets; 3) the installation process for installing one piece pads and/or padlets; etc.

A Wilwood vendor is making me brackets which will allow me to run the W6A caliper on the front with OEM style/size rotors such as DBA 4000. I don't think the economics justify the cost of 2 piece rotors.

http://www.wilwood.com/CaliperList1.aspx?subname=W6A

My favorite track pads are the Wilwood H which run $210 delivered for the W6A. I'm aware that the W6A is not the "best" caliper available but I'm thinking for HPDE it will be more than adequate. Not the best but a whole lot better than the stock calipers.

The W6A pads don't have the most surface area of the Wilwood calipers but they do have the most volume (i.e., cubic inches).

The vendor tells me the complete setup including calipers, brackets, pads, hoses, etc. will cost right around $1,600 delivered.

At this point I'm thinking of retaining the rear OEM calipers as they do so little I can live with them.

I'd like to hear your thoughts?


Rick

Bill Dearborn

Sounds like a good deal. I just sold the LG G Stop kit I had on my C5Z and before selling it I was tempted to see if somebody could custom make brackets to fit the calipers to the C6Z. I never had an issue with the Wilwood calipers and I had them on my 03Z for 4 years and a lot of track miles. Consistent stops time after time with low cost, long lasting brake pads. Even on the 03 I quickly paid for the cost of the kit in the reduced cost of brake pads. On the C6Z spending $400+for front track pads and almost that much for street pads probably would make the payoff come about quicker.

Does the W6 caliper use the 7420 or similar pad?

**Answered my own question. The 6617 is wider, longer but thinner than the 7420. About the same thickness as the 7416. Not sure how that would affect wear characteristics.

Bill

oldmansan

Personally for that price I'd just go with StopTech, AP, Brembo etc fronts. You'd get the advantage of two-piece rotors which will save quite a bit of rotational weight plus you'll have a much better caliper/pad setup in my opinion.

Any reason you can't use the stock front calipers on the rear?

San

Bill Dearborn

I haven't seen any comparisons of rotor ring life with the Stop Techs but the two piece Wilwood's for the C5 were not cost effective against the NAPA OEM style rotors. With C6Z GM rotors being delivered to my house for $380 for a set of 4 they are about $120 more than a set of the NAPA C5 rotors. I just tracked my C6Z for 6 days with a set of stock rotors that had 14K miles on them when I started and had some visible wear. The front rotors are still in excellent shape although more worn with a couple small cracks starting at some of the holes. The Stop Tech rotor rings would have to last quite a bit longer or they would have to be cheaper than the Wilwoods.

Bill

gkmccready

The G-Stop bracket and the C5 NAPA rotors should have worked fine, no? I mean, since the C6Z brakes bolt right up on a C5/C6 they should go the other way just fine, too...

The thing with the SL6 models is that they're limited to 13in rotors outside of the one special model that'll do 14in.

Bill Dearborn

The 14 inch SL6 just uses a different bracket. Everything else is the same. LG's bracket is a different layout than the Wilwood kits use due to the fact he uses the regular SL6 caliper instead of the thin caliper. That is why I was thinking about Custom made brackets so I could run a larger rotor. Just another half inch or so radial distance on the bracket and the diameter would have worked out. Not sure it would have worked with the C6Z rotor but if it could then a couple hundred for special brackets would have been a cost effective solution.

Bill

gkmccready

I, uh, don't believe that's true about the 14in SL6... the caliper body needs to change to clear a rotor with that OD. Even the 12.9in is really close to the body. And Lou's kit needs a special bracket because it uses the standard rotors, not just because of the SL6 caliper. The Wilwood bracket is designed for the Wilwood rotors which actually pull the disc further in-board... I know this because we started with the Wilwood brackets by mistake... and, FWIW, the true full width SL6R works fine with LGM's bracket...

Bill Dearborn

I think we are saying somewhat the same thing. I had LGMs kit so I know the bracket works just fine. However, the only difference in the Wilwood kit caliper and the LG caliper is the width of the caliper not the radius. The studs on the caliper bracket are long enough that you could put washers on them and push the caliper out about a 1/2 to 3/4 of an inch which would take it from a C5 diameter rotor to close around 14. When I put the LG kit on my car my rotors would hit the caliper slightly when they got hot. I used the special washers (you don't buy them at the auto parts store) that came in the kit to space the caliper out so it would not be hit by the rotor. However, the bracket was still going into the recesses in the caliper so the two were locked together and the bracket was still absorbing the brake force and not the studs. If I used washers to move the caliper out any further the studs would be taking the braking force and I am not sure they could handle it. Thus the need for a different bracket.

Bill

gkmccready

If you push the caliper out far enough to clear a rotor larger than 13 inches the top of the pad won't be making contact with the rotor... so to keep proper pad/rotor contact and fit a larger rotor you need a different caliper body that can handle the larger radius...

rikhek

Bill

What pads are you running with the stock rotors that lasted 6 days?

I'm assuming stock calipers?

Are you running R compounds?


Rick

Bill Dearborn

I have been running a mixture of pads. The first day I used up the original pads that had 14K miles on them. Then somebody gave me a well used set of Hawk HP+ pads that got me through an autocross and 2 1/2 more days. The last two days I used the Cobalt CSR single piece pads I got from LGM. I have been running some old EMTs on LG World Challenge wheels until I have burned them down. They actually haven't been doing to bad although they do not have enough traction for the CSR pad's grip. The last two track days were the first time in years that I have been into the ABS in the hard braking areas at Watkins Glen. Of course my speeds at the end of the straights are 5 to 10 mph higher than with my C5Z on R compounds but I have been letting off the throttle before reaching the braking point. I still think I wouldn't have been into the ABS if I had been running R compounds even though I would have been going somewhat faster due to higher corner exit speeds coming onto the straights. I haven't pulled the wheels to check the pad wear yet.

I have 6 more track days left this season and the EMTs probably will last through them unless a couple of autocrosses wear out the rear tires.

Bill

95jersey

Just found this post. I think this option for $1600 is great. The stoptech is $3100. That is a savings of over $1500. I have used the SL6 on my C5 and it was a GREAT caliper and the H pad is an awesome pad that simply lasts forever.

Like you posted above, I am sure Stoptech is better, but the W6A caliper, I am sure is no slouch. The quick removeable pins will be a JOY compared to the POS paddlets. Also, isn't it made in America (unlike Stoptech...but could be wrong).

Would 2 peice rotors be better...sure
would they be lighter...sure
would they last longer..."maybe" a little
Is this worth the extra $1500...we'll if you got the extra cash to spend...sure.

BUT to save $1500 and use the less expensive OEM rotors is a huge plus. I finally need to replace my OEM front rotors from LAST year. The last time I replaced them was in July 2008. Since then, I have done 8-10 track days on them and a full fall/winter/spring of street driving. They are cracked up pretty bad, but I bet I could still get another day or so.

The one concern that no one could answer was if they fit under OEM rims. I have both the 2006 style rims and the 2009 spyder and would hate to buy the kit to find out it doesn't fit. We know the Stoptech and the Brembo kits fits, but even Wilwood themselves didn't know if it would fit.

Please let us know when the come in, take pics of them side by side with OEM calipers and of them mounted (if they fit). Good luck and keep us posted.

0Todd TCE

Yes. The caliper body is nearly identical in overhang to the massive oe caliper.

95jersey

Also, does the package include the thermolock pistons?

oldmansan

Stoptech 14" two-piece rotor ST-40 kit is $2495 at Zeckhausen. Even Stoptech will tell you the ST-60 won't provide any better performance than the ST-40, just a little longer pad life. I don't think that $1600 for one-piece rotors and the Wilwood calipers is a bargain, especially if the rotors are only 13". Just my opinion.

If you do go with the 13" rotors I'd definately do some brake ducting.

San

95jersey

I just don't feel comfortable replace a 6 piston OEM PBR caliper with a 4piston kit, even if it is Stoptech. It's not about better stopping, I don't expect any. As stated above, I want better pad life, easier pad changes and a LARGE caliper capable of taking abuse lap after lap. I could probably put C5 brakes on my Z and still have the same stoping distance (the first 10 laps). I am not sure if the smaller caliper is smart to put on the front of a 500rwhp car. I think you'd be pushing that caliper to it's very limit on a road course lap after lap.

The OEM caliper is completely up to the task, it's just expensive pad costs, poor wear, and a PITA to change pads. From my experience with Wilwood, I am sure they are as good or better than the PBR caliper. If they work no better than the OEM caliper, I would be more than satisfied. Just hate removing the caliper each time I do pad changes. I don't beleive

drivinhard

Is that Dave Zechhausen from NJ? I remember him from probably a decade ago, used to auto-x a Taurus SHO, did brake upgrades and kits for impallas and SHO's way back when.

guess he's really taken off!

"World's #1 retailer of StopTech products for 5 consecutive years"

rikhek

The C6 Z06 rotors are 14" x 1.26". Not 13". This "kit" will use stock OEM sized 14" rotors.

0Todd TCE

Optional.
With such large rotors the benefits are diminished some also.

ghoffman

You all know I like Wilwood products in general, but the W6A is a total POS. If we were to do basic system requirements like weight, stiffness, thermal isolation, serviceability, pad design, pad thickness, etc, it is abysmal. Almost any other caliper (except the OE C6Z PBR caliper) is an improvement over the W6A. If you have to get this "caliper", at least ask for a few extra of the little "c" clips and pins. In general, any caliper that uses pins that add mass with zero stiffness should be avoided.