what is the difference between these two wilwood kits other than the rotor diameter?

http://www.flynbye.com/catalog/i18.html

http://cgi.ebay.com/WILWOOD-DISC-BRA...item43a122ecbd

 

The first kit from FlyNBye is a durable normal duty useage kit for a third gen with decent size caliper bores and pad volume aganst a thick heavy duty vaned rotor that will disapate nrmal repetive braking heat.

THe ebay offered kit? will get you into trouble REAL QUICK on the street with undersized caliper bores and under weighted rotor thickness. THey are for a full drag car intended to make one stop and then rest for awhile. They will not diapate heat fast enough from normal street use and can get overheated quickly causing fade and warped pad buildup on the rotor surface. PLUS- Most importantly, those aluminum hubs are not heavy duty enough for hard cornering and will crack. Global west had to nake an aluminum hub for Wilwood that could withstand a road race chassis- that unit from Wilwood is STRICKLY for drag use in a straight line car seeing no lateral loads.

 

That eBay kit is this:

http://www.wilwood.com/BrakeKits/Bra...emno=140-11275

Wilwood states that it is for street use. The Wilwood drag only kit is a 10.75" rotor that is .35" thick.

Spohn I know for sure offers the street & drag only version of that 10.75" rotor. I highly doubt Wilwood would make the claim that its for street use when the liability is through the roof for someone to buy it and have it fall apart after 15 mins of around the town driving. I personally think the caliper is too small myself, but Wilwood does have a payroll of engineers that know far more about how well the rotors perform for the stated application than I do.

I've been eyeing that same kit and I've made a contingency plan for it just in case what everyone on here has been saying about the rotor being too thin: Dynapro 6-piston calipers & 1.25" thick rotors that are ground down to meet the 1.1" thick maximum of the caliper:

http://www.wilwood.com/Calipers/Cali...emno=120-10121

http://www.wilwood.com/Rotors/RotorP...temno=160-3871

The caliper is just a tad smaller than stock and the rotor has enough meat there for grinding I think.

 

I was wondering if that might be the case, but I checked the part numbers on Wilwood's site and they're for the "street" version not the "drag" version. I didn't see a kit straight from Wilwood with the beefier caliper that looks to come with the flynbye kit. Just wondering how much difference there will be in stopping and, more importantly, what mods are required? I'd rather get a kit that doesn't make me pull the spindles if possible.

 

the woods hold up just fine for street and strip... even with Pizza Cutter wheels and tires MT on them.

 

flynbye's kit is a complete bolt on deal, with a new modified spindle, so you have to pull the spindle. not a big deal

tha other kit requires to to modify your spindle, cut off the old caliper mount ears, drill and tap the dust coverholes ect.

both require work.

personally, i would go for flynbyes kit. Its a MUCH better street/track setup. The other kit will probably work on the street, but is less than ideal if you really want to push the car.

 

The beefier caliper that Flynbye uses is a radial mount caliper whereas the Wilwood kit is a lug mount caliper. Wilwood made its kit to be very easy to install after you have the spindles modified. Looking at Wilwoods mods, most people couldn't do the work without having someone at a machine shop do it for them. After that, if you can put a bolt in a hole & follow directions, you can put the kit on.

I can't imagine the wilwood kit having braking performance that is less than equal to stock, but then again it depends what you're looking for. The flynbye kit is definitely better than stock, but if you know what you're looking for, you can get a beefier lug mount caliper from Wilwood for their kit. I've found that the 6-piston Dynapro caliper will interchange with the supplied 4 piston caliper and its almost the same size as the stock caliper.

http://www.wilwood.com/Calipers/Cali...emno=120-10123

Either way you go, you'll have to pull the spindles. Question is, how much work are you willing to do after you pull them.

 

Another big consideration for selecting brakes that many people overlook is the weight of the car they are going on! The solid rotors work great on a 2,000 pound roadster, but I don't think I'd use them on a 3500 pound Camaro....same goes for the aluminum hubs, fine on a light car or a drag only setup but I would want something a bit heavier duty on a heavy car!

 

Its not the caliper thats the trouble, its the thinckness of the rotor that is the problem. That rotor is WAY too thin to disipate heat on a 3300+ lb car. You operating heat will be tto high and you will not have any longevity or reliabilty out of that light weight rotor setup.

The you are talking about shaving down 1.25's on a lathe into 1.10's.

I think you need to learn more about brake performance before you do something dangerous like you keep hinting towards. You start shaving off rotors and turning them under the minimum thinckness of each side of the vent youy aare going to run into serious failure problems. Its not the overall thinckness of the rotor, its the gap in the center (the vent) and whats left on the two sides of the vent that is thinned down and not enough mass to disipate heat. the metal will hootspot, can crack and fail also.

 

Nope, I'll have them Blanchard ground to size. You load the rotor into a magnetic chuck and a very large grinding wheel very slowly removes material at something like a couple thousandths at a time. This ain't my first time at this. I've made and modified rotors for Formula SAE cars before, and this isn't any different. The rotors I've made were 8" x .15" drilled & slotted rotors and at that they were way oversized for even a 1000lbs car doing a panic stop from 70mph and they showed no signs of distress or failure after years of hard racing use. Just need to be careful, take some measurements, ask a few questions, and gingerly experiment with them before going hog wild and making a custom setup.

 

Theres a big difference between 4 open wheel air cooled motorcycle rotors on a go kart - compared to a full sized car. You are wrong in preaching this would be ok and you can potentially indanger some 18 year old kid heeding your advice and trusting what you say to be safe. It is NOT. This is why there are simple DOT standards in turning street rotors compared to non regulated race parts.

The rotors you speak of are not ground down to 5/16th of an inch, they are manufactured that way and properly heat treated after being manufactured of the best iron in a solid design with pressure on both sides of a non vented rotor. Those rotors are nothing like a cast vented rotor. You are comparing apples to oranges.

It is not safe period. Don't trust what I say? call any manufacturer and ask them your intentions, They will tell you no, do not do turn down one of our rotors undersized.

 

FSAE is not a go cart, period. I have had my rotors reground flat at least twice since I've owned it and possibly even more. I've yet to have a problem with brakes in the 6+ yrs I've been driving on them.

If it'll make you feel any better, and you should do this as well since you tell a lot of people what to do, here is my disclaimer:

I am not an engineer and have never designed a rotor period. All that I post is my own opinion and take it at that. I can not be held responsible for any results good or bad.

Also, I'm not saying that its safe. Care to point out anywhere I did say that it was? I was pointing out that it might be possible to grind down a bigger rotor to a size that would work with a bigger caliper that fits on the Wilwood kit. Thats all I've said so far about grinding rotors down a ton.

I'm comparing a casting to a machined billet rotor. The rotors I made were made from 80-55-06 ductile iron and the Wilwoods are probably made from SAE J431 2500a cast iron. 80-55-06 has an ultimate of 80ksi and a yield of 55ksi whereas the SAE J431 is 25ksi ultimate. I understand they are heat treated, but Blanchard or Surface grinding won't affect the heat treatment if done properly.

http://www.matweb.com/search/DataShe...c177d80&ckck=1

Then I must be ridiculously lucky for having my rotors ground flat twice. No manufacturer will say that grinding rotors is fine, they don't want to be on the hook for Rufus grinding too much material away and then having the whole thing fall apart on them and end up getting sued.

The two major dimensions to be concerned with are the thickness of the ears attaching the rotors to the hub and the thickness of the rotor face to the vanes. If either of those get too thin, the rotor is worthless. I'd be more concerned about the ears getting to thin rather than the rotor face to vanes getting too thin.

I'll buy Wilwoods kit and use it. In fact the only thing I plan on changing in that kit is the caliper to the larger Dynapro. If I don't like how that's working with a .81" rotor, then I'll try the rotor mod myself. Up until I start messing with the rotors, if my brakes fail, the egg is on Wilwoods face.

 

I'm probably going to replace my spindles anyway. I had the front calipers both freeze after driving my car the first time in a couple years. Unfortunately, with the 406 and having gotten out of a z71 and into the IROC I didn't really notice anything wrong other than a stiff pedal until I saw chunks of red-hot rotor flying out from under the car. So I'm a little worried about what abuse the spindles took lol. I was just hoping to avoid having to do alot of here/there shipping of spindles for modding.

 

Hawks Thirdgen sells stock spindles for $50 each:

http://www.hawksthirdgenparts.com/ca...eusedlorr.aspx

Take some pics of the spindle, it may not be as bad as you think.

 

That kit is a waste. Undersized rotors and undersized calipers for a 3500lb car going around a road course. I'd stick with the stockers until you are ready for a real setup. Ed's Wilwood kit on the other hand is excellent for the price.