Steering, Suspension, & Brakes

I learned that "cool-down laps" are a very good idea if you're gonna do a "track day"!

I pretty well cooked a new set of EBC "Green Stuff" pads on Sunday.

Learn from my mistake. The car stopped well enough, but the pedal felt mushier each time I went out on track throughout the day, and it was pretty darn scary feeling for the drive home. I don't think it was the track time that cooked them - my mistake was running hard and then stopping abruptly. When I took the pads out, I found they were kinda crusty looking all over, plus there was bubbly black residue all around their perimeter. (I probably overheated the fluid too, of course...)

(One of the Miata's I was running with melted a set of pads much worse. He actually managed to push a brake piston right through the backing of a pad. I wish I'd taken a photo of that!)

Apparently Green Stuff pads aren't as appropriate as "Yellow Stuff" pads for track day use! EBC rates the "Yellow Stuff" compound as superior in both cold and hot friction, plus they'll take a higher max temp.

One of British V8's sponsors, John Targett at Targett Motorsports, offers both Green Stuff and Yellow Stuff pads in MGB V8 (slightly larger swept area) versions at a VERY competitive price. John also sells really nifty grooved and dimpled EBC (top-quality, Made-in-England) rotors in two or three versions. The top-of-the line version is 0.430" thick (so there's more mass to dissipate heat, but not as much as the factory MGB GT V8 rotor. You can use these with the standard MGB caliper if you use John's matching EBC pads.) At the moment I'm still undecided if that's what I'll be putting on my car. (Wilwoods are lighter, but pricey.) For sure, next time I do a track day I'll try to get in cool down laps before I pull into the paddock, or at least driving a lap or three around the the paddock before parking.

For more info, scroll down to the bedding-in section of this page: [www.ebcbrakes.com]

John's contact info: [www.britishv8.org]

This is why oversize brakes are such a great idea for modified cars. Yes, stock MGB brakes will still stop the car just fine, but asking them to do it repeatedly from high speed over a longish period of time just heats them up until they can't get rid of the heat fast enough. I guess you could think of it as putting all of that horsepower right into the brakes, because except for friction losses that's pretty much what we're doing. With the 4 they could do it but with a strong V6 or V8 it's a little much to ask.

Jim

Great info for future reference.

I find that carrying more speed through the corners, though, leads to much less abuse on my stock brakes.



Edited 1 time(s). Last edit at 03/14/2008 10:22AM by MGBV8.

Curtis,

Production racing in the SCCA - all Production classes - limit all the cars to stock brake rotors on the front brakes. A little concession is given to some cars via rear disc brake upgrades.

Rear disc brakes seem to provide little improvement as most of the braking is accomplished on the front end. MG B's are allowed upgrades to rear disc brakes with the spec that the rear rotor must be smaller than the stock front. It's in the GCR.

Everyone seems to use the Hawk Blue pads in SCCA Production racing.

Everyone races with much loss braking after only a few laps in SCCA Production class road racing. Makes it interesting. Save your brakes for the last laps ?

We are planning on some brake rotor upgrades in GT 2 with the RV8 - unlimited braking modifications are allowed in the GT 2 class. How fast do ya 'wan 'a go, how much you wan'a spend.

Phillip G

I remember that on Plumstead's board Paul Hunt was always defending stock brakes because they would haul the car down from high speed and skid the tires. I never could get through that yes, they would. Once. I grew up in the foot hills of the Blue Ridge mountains and spent a lot of time as a teenager tearing up and down some pretty challenging roads in my '64 B and I know it didn't long to run out of brakes. One or two long hard stops and it was pretty much over till they cooled off.

I have a set of MGC uprights that I plan to bolt '79-'83 Toyota 4X4 calipers ($33 at Advance) on to. MGC's used the same calipers as TR6's and there is a common swap used by the TR guys outlined at....

[www.turbo-tr6.info]

It uses Cressida rotors ($19) that may or may not be able to be used with the C uprights. Maybe Pugeots will work. I'm sure I can find something ventilated that will.