Mikelly Posted January 22, 2001 Share Posted January 22, 2001 OK guys, here's the deal: I dropped off Jim's (BLKMGK) Kmember and I looked at his 5 lug front hubs and it became clear to me that in order to use my existing brakes I would need MUCH larger spacers. If I need to buy or machine new spacers, right now would also be the right time to upgrade the front brakes... I'm looking at hitting some high speeds, so I'm thinking 12.5-13inch rotors... Any ideas would be helpfull! Mike ------------------ http://hometown.aol.com/dat74z/myhomepage/auto.html "I will not be a spectator in the sport of life!" mjk Quote Link to comment Share on other sites More sharing options...
BLKMGK Posted January 23, 2001 Share Posted January 23, 2001 SCCA - would the 12.? conversion you're working on for a ZX work? How big can we go before we get into silly money? Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 23, 2001 Share Posted January 23, 2001 Jim... (et Mike) first ALL of the brake pics i have on the net are for Z cars.. (70-78) i have done a few ZX's but none are shown on the site. the big brake kit shown is on a car near Maryland (i think).. i am currently doing a ZX setup for a local guy and possibly a setup for Les at Classic Datsun. as far as pricing it doesnt really jump till you hit 14" rotors. 13" only add $75 a pair to the total price. the big jump comes in IF you want to use 1.38" thick rotors then the calipers are almost double in price! this is more nascar high speed use and definitely overkill - althooogh i did sell a setup of this for someone who is putting it on a european escort with a sierra imported IC turbo motor.. all factory ford rally stuff it should FLY... Mike Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted January 23, 2001 Share Posted January 23, 2001 a question -some of the willwood & other aftermarkit calipers have same bolt pattern as early z caliper ears.need an adaptor to put coleman rotors on z hubs with willwood calipers. Quote Link to comment Share on other sites More sharing options...
Mikelly Posted January 23, 2001 Author Share Posted January 23, 2001 OK, Then here is the question... How much are we talking to put 13 inch rotors (1.25 or smaller thickness) and wilwood billet calipers on the front of a 5 lug Z? Mike ------------------ http://hometown.aol.com/dat74z/myhomepage/auto.html "I will not be a spectator in the sport of life!" mjk [This message has been edited by Mikelly (edited January 23, 2001).] Quote Link to comment Share on other sites More sharing options...
TimZ Posted January 23, 2001 Share Posted January 23, 2001 quote: Originally posted by Mikelly: OK, Then here is the question... How much are we talking to put 13 inch rotors (1.25 or smaller thickness) and wilwood billet calipers on the front of a 5 lug Z? Interesting side note on the Wilwood billet calipers... I talked to a tech at Wilwood a while back, and inquired about 'upgrading' my current cast Wilwood calipers (AZ Zcar - similar to Pete's) to the newer billet style. The tech told me to stick with what I had if I was worried about caliper stiffness, as the billet calipers were not as stiff - they just look nicer, and were more popular with the hot rod/show car crowd. Now, I'm sure that nobody will believe me on this, as it still sounds strange to me. All I can say is that it wouldn't hurt to call Wilwood and confirm this - I believe that the billets are quite a bit more expensive. Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 23, 2001 Share Posted January 23, 2001 yes most all aftermarket calipers come with a 3.5" B.C. (bolt circle) if you use this directly then you need to helicoil the strut to standard thread and the rotor is limited to a 11.2" roughly. this is what i use for the next step up from the 4 runner i have pics on the web of this already. 13" rotors are about $130 ea outlaw 4000 are $175 ea pads HPS+ $60 caliper mounts and rotor adapters depends where you get them. you would have to buy your own 8" billet to make the hats they endup costing $200 pr or so after machining. weldon caliper brackets are $30 pr and bolt on are $100 pr. IMO going from a 12.2 to a 13" rotor is minimal change. maybe for a GT1 race car but you'll never see it on the street.. and i have bolton brackets and rotor adapters here for a Z with this rotor size. ------------------ Mike mike@fonebooth.com http://www.fonebooth.com/brakes.html raceparts and brake upgrades. Quote Link to comment Share on other sites More sharing options...
Drax240z Posted January 23, 2001 Share Posted January 23, 2001 Hey Mike (scca) you say that these are big for the street... Do you remember what Mikelly is doing with his car? Personally at speeds 190mph+ I don't think you can have too much brake! Whether on the track or on the street. ------------------ Drax240z 1972 240z - L28TURBO transplant on the way! Drax's 72 240Z Turbo Quote Link to comment Share on other sites More sharing options...
Guest Anonymous Posted January 23, 2001 Share Posted January 23, 2001 Unless I'm mistaken, the circuit Mike will be running is pretty straight and has alot of runout. There are only a few major turns in the whole course. Its not quite like road racing with lots of corners and continued braking required and the other traffic on the track. Definately want some good brakes but there is still the possibility of overkill IMHO. Lone Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 23, 2001 Share Posted January 23, 2001 i missed in making my point.. the 12" will do the job on his application.. 13" IS overkill IMO. nice but not necessary. his limitation will be the tires on the car not the rotor size. a GT2 car uses a 16x10" rim with up to 12" slicks WAY more than any street car will use and the compound is far stickier ... yadda yadda... and they use only the 12.2" rotors hope i cleared itup a bit... ------------------ Mike mike@fonebooth.com http://www.fonebooth.com/brakes.html raceparts and brake upgrades. Quote Link to comment Share on other sites More sharing options...
pparaska Posted January 24, 2001 Share Posted January 24, 2001 I have to agree. 12" would be plenty. There might be some benefit in going with a curved vane rotor, but I'd definitely fab up some strut housing mounted cooling hose fittings in place of the OE dust sheild and run it to the air dam. Unsprung weight is the enemy. Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 24, 2001 Share Posted January 24, 2001 my 12.2" rotors are curved vane and i generally add pad wipers for street cars to help deglaze the pads . the rotors are also 1.25" thick plenty of brake for almost any application.. i'm biased of course but i think my setup is visually more appealing than the AZZ setup i've seen in their catalog.. still havent seen a setup in person yet though. Mike Quote Link to comment Share on other sites More sharing options...
Mikelly Posted January 24, 2001 Author Share Posted January 24, 2001 So Mike, Minus the "Hats", 13inch brake kit including the rotors, pads, calipers and bolt on brackets is about $770, and the 12inch version will run approximately $695. DO you have these in stock? Mike ------------------ http://hometown.aol.com/dat74z/myhomepage/auto.html "I will not be a spectator in the sport of life!" mjk Quote Link to comment Share on other sites More sharing options...
pparaska Posted January 24, 2001 Share Posted January 24, 2001 Mike (scca), what are pad wipers, and how do the work/install? TIA Quote Link to comment Share on other sites More sharing options...
Modern Motorsports Ltd Posted January 25, 2001 Share Posted January 25, 2001 quote: Originally posted by scca: the 12" will do the job on his application.. 13" IS overkill IMO. nice but not necessary. his limitation will be the tires on the car not the rotor size. a GT2 car uses a 16x10" rim with up to 12" slicks WAY more than any street car will use and the compound is far stickier ... yadda yadda... and they use only the 12.2" rotors Mike and Pete, on what basis do you comment/state so firmly that 12" is fine for Mike's car and 13" is overkill? Rotor mass/requirement is a squared relationship with speed so Mike does introduce some greater than normal requirements. AIR, GT2 cars do not have the power/weight ratio we're running and thus we hit higher top ends and thus greater speeds to close. (are those 12.2's 1.25" or narrower?) I don't have my calc's for my setup scanned online for others to follow thru with their setups but just offhand a quick rule was your rotor temp would double if you increase your speed ~40%. So if they're just tolerable doing a 100mph=>zero stop now and you want to be able to stop from 140mph with same brake performance you need to double your rotor mass to stay at that same temperature threshold. I'm not saying Mike and Pete are wrong, but I'd certainly walk thru Puhn's calc's before I tossed even $100 at a brake upgrade for any serious application (ie. road racing or high speed open road stuff). I'd also like to know if I come around a bend in Nevada and someone up ahead bit it (or an animal) that I could confidentally throw out the anchor from 180mph=>zero without sweating too bad. You also mention Mike will do open road racing....I'd be surprised if he doesn't get to some track lapping days as well. If he was up here at SIR he'd hit 160-170mph if he had the balls going into turn one (no offense Mike, few have those big balls:-) and 12" <1.25" rotors I'm quite certain would not cut it for an adequate heat sink. Ross C I'd have put 12's on my setup if they'd have been adequate but Puhn's gospel book said they wouldn't cut it so 13's went on. For reference my 13" rotors are 19lbs and the 12" rotors I modelled were 14lbs. So a 12" rotor wider than what I modelled could fit in the middle and may be the perfect. (my 3100 lb w/ driver 280ZX doing a closing speed of 145=>60mph required more than a 12" rotor on a roadcourse condition FWIW, Mike's lighter but faster setup would be interesting...) Quote Link to comment Share on other sites More sharing options...
randy 77zt Posted January 25, 2001 Share Posted January 25, 2001 i put a willwood 4 piston caliper/coleman 12" stock car rotor setup on a friends 240 z road race car and brakes were tortured for 3 hours at laguna with no problems.on a open road course brake pad choice will be critical because some of the heavy duty road race pads wont grab when cold-if you have used brakes in last 10 miles and then go for them you will get a thrill.but there are lots of pad choices for willwood/outlaw 4 piston caliper so i know you will find some pads that will work.the willwood polymatrix b pads i use on back of my car work but really mess up wheels.you will be upset after you find that hot pad material burns its way into your wheels and does not come out.if you use race calipers and pads you will have dirty wheels and squeeky brakes. Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 25, 2001 Share Posted January 25, 2001 pad wipers are commonly referred to as "slots" or slotted. you have 3-4 curved grooves ground into the faces of the rotor. as you step on the brakes these will cut into the pads and deglaze them. best if you use with a HP pad not a oem one. and mike i dont have bolt on brackets here for the 13" rotors no one has asked for a set. also the rotor adapters affect the bracket so you would have to make your hat the exact same dimensions as mine to use my brackets and unless your physically doing the lathe work you wont save any money - at least i think yu wont save any. ------------------ Mike mike@fonebooth.com http://www.fonebooth.com/brakes.html raceparts and brake upgrades. Quote Link to comment Share on other sites More sharing options...
pparaska Posted January 25, 2001 Share Posted January 25, 2001 Ross, no doubt, I haven't run the calcs. I have Puhn, but I'd love to see your analysis - sounds interesting. I'd guess that weight has a linear effect on needed brake sizing, maybe more. I was factoring the weight of what I think Mike's car would be (2800 with driver and fluids) and it just seems that over 12 inches with 1.25" wide rotors and ducting would do the job. But you're right, if your planning on 180 mph and the possiblity of having to panic slow/stop, run the numbers. Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 25, 2001 Share Posted January 25, 2001 Ross, my 12.2" rotors are 1.25" thick. they will take way more heat than any oem mustang 13" rotor or whatever oem rotor you find.. back to my original comment i think its a TIRE issue, now tell me how a non-racing slick is going to slow down faster than a GT2 car. sorry but i dont care about the power-weight ratio etc.. FYI a "real" GT2 car is running about 350-400 HP and 12" bubble gum slicks at around a 2400lb total weight. (the lighter cars are around 2100lb...) oh and GT2 cars easily get to 150+ mph on tracks with long straights. i imagine IF they were geared for TOP MPH they would get to the 180 range.. hwo does the rotor being larger help if this is the case (assuming i am correct on the tire issue) .. Mike Quote Link to comment Share on other sites More sharing options...
Guest scca Posted January 25, 2001 Share Posted January 25, 2001 while i'm on the soapbox i'll continue. just in case no one here realizes the brake upgrade i sell IS a late model stock car setup. those cars generally run 2400-3000 lbs and upwards to 700 HP. and run slick 15x10's all around usually. now tell me that that isnt comparable to the Z power ratio! ok enuf ranting Mike Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.