Newer Car GT40 branded caliper brake pads

I have a newer car, #2388, sequence 339. I have the GT40 branded calipers. I'm assuming they are the same as the old Wilwoods and use the same brake pads. But you know what they say about assuming.

Does anyone happen to know if they are the same as the old setup and only new graphics?

Thanks in advance

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DaveM

Supporter
I think the new ones are Wilwood FNSL4R Forged calipers versus the previous billet ones. Otherwise same dimensions and pads.
 

DaveM

Supporter
Hope you're planning on changing the pads. You'll fry the Wilwood BP-10's in about 2 laps. BP-20's won't cut it either.
 

DaveM

Supporter
Initially I tried 'B' pads. Didn't fade, but low initial bite. Went to 'A' pads. Better, but still not as much initial bite as I'd like. Don't know anything about the BP30 or BP40 pads. Wonder about some of the other brands ceramic compounds? I also track a Lotus Europa and know it weighs 1000 lbs. less, but the Europa on 'B' pads brakes way better than the SPF with high initial bite. Assume you're going to Road America? Let us know what works and what doesn't.
 

Mike

Supporter
I have used the BP40’s the last few years on the track and very happy with the breaking and feel but it still never feels like a newer car
 
Dave (and others), thanks for the prompt. The track days were great. For me and the car, as much about sorting as performance, this was very first time out in anger. A number of things came up that required dealing with and have me started on a new ToDo list. Before I get to the brakes, other things I learned/happened.

A week prior to the event the clutch arm failed. I have an external clutch slave to clutch arm, rod/fork arrangement. The geometry on the slave to clutch arm was the culprit and bent the clutch arm to the point of failure. With the substantial help of Randall at Performance Unlimited in Wisconsin, I removed the arm, he took the bent disaster and straightened then reinforced with steel and tig welded the whole mess back together (many hours contained in that one sentence). This had me sure I wasn't getting the car in the trailer up until a few hours before departure. But the fix worked perfectly and I adjusted some of the geometry to prevent a repeat performance. Would not have made it without his help.

Due to this, I didn't get around to getting other pads to try.. :confused:

Definitely need Valve covers vented into a catch can/breather arrangement. After 4-5 laps of going hard, the breather was overwhelmed by oil rich blow by and started to spit oil onto the headers. #smokescreen. 99% was coming from the rear valve breather cap. I McGyver'd a solution together by creating a remote breather setup with 3' of hose sealed to the valve cover to get me through the two days (thanks Ace Hardware). Worked fine, now time to make a permanent solution.

Now to the brakes. I had the factory installed pads that I am sure are the BP20's. Wear was high. I'm up for new pads. Feel was OK but more pedal action/movement than brake fade was apparent after 4-6 laps. As this was outing #1, I wasn't going full steam, but pretty quick. With a better pad and some work on bleeding and feel prior to the next event I feel I will be able to go in deeper with more confidence.

So sorry, no comparisons yet. Next outing I plan to have a few different compounds to try.

Good news side:
- Car ran great. I have the webers working well. Engine was flawless. Sound - intoxicating.
- Gear shifts were very slick on the way up. Need to work on footwork for heel and toe as I downshift in tricky corners. Got better as the weekend progressed
- Suspension set up felt really good first time out. Bump and Rebound settings were good. Grip, turn in and balance were great. Easy to predict and throttle steer through the corners with confidence.
- Driving position was comfortable. Will be adding a 5 point going forward and make sure I can get them tight. The G's makes staying in the seat a chore unless I'm really snug in there.

I know that's a little be of drift from a brake pads discussion, but hopefully useful context and info.
 

Ron Scarboro

GT40s Supporter
Supporter
What are the part numbers for the front and rear. I looked on Summit Racing, but there are many different part numbers.
 

Neil

Supporter
"Definitely need Valve covers vented into a catch can/breather arrangement. After 4-5 laps of going hard, the breather was overwhelmed by oil rich blow by and started to spit oil onto the headers. #smokescreen. 99% was coming from the rear valve breather cap. I McGyver'd a solution together by creating a remote breather setup with 3' of hose sealed to the valve cover to get me through the two days (thanks Ace Hardware). Worked fine, now time to make a permanent solution. "

See page 62 of the hard-cover "Racing In The Rain". JWAE had problems in 1964 with the valve cover vents on the 289 as well.
 

DaveM

Supporter
Neil, I feel about a million years away from any comparison to JWAE and their challenges and achievements on the track, but appreciate the historical connection. Dave has answered the pads question, thanks.
 

Richard

Supporter
I’m going through the process of setting my car up to race. Sent it to Olthoff for a couple months over the Winter and did essentially all R spec upgrades. Had many other track items installed by my race mechanic. Took the car to The VRG school 2 weeks ago to get my vintage license and had the issue of the rear brakes locking up and spinning the car in the threshold braking exercise, despite having the bias bar set to the front. I was running BP40 pads. Tracked all week last week and rears would lock first despite bias bar all the way front. I’m just switched the rears out last night to the original BP10 pads (which I had saved) to just see if that will make the bias better. Testing the car on Monday. FYI I’ve talked to other people who have raced SPF GT40s and they ran less aggressive pads in the back. Olthoff says to run Carbotech 7416xp10 pads, which I have sitting on the shelf, but do not want to run them until I have some baseline numbers at my home track and confident in the brake bias.
 

DaveM

Supporter
Thanks for the track info Richard. Strange that you still locked rears with bias bar set to fronts. Were you downshifting at the same time? I've found the GT40 very touchy to heel and toe downshifts. I would agree a less aggressive rear pad is warranted as the calipers are identical front to rear. Interesting recommendation on the Carbotech pads by Olthoff.
 

Richard

Supporter
They were locking up in a straight line threshold braking exercise...not during a downshift. It was odd. The bias bar appears functioning fine, the masters are new from Olthoff. On the track you would never slam the brakes on as I was doing in the exercise, unless in an emergency...but that fear prevented me from aggressive lily getting on the brakes on the track. I’m anxious to see how the BP10s in the back work with the BP40s in the front. If that solves the locking problem, then I will determine exactly what compound I need in the back to have the best braking. Trial and error I guess.
 
Richard, I took a look at the posts from your acquisition of the car. Great choice BTW ;) Thinking about your use, I thought you might like to consider a turkey pan set up to to minimize the fuel boiling potential in those webers and to shield that crossover fuel line. Here's what I did. I don't have before and after reference for performance or heat mitigation, but it sit flush with the clam shell and also prevents road debris from landing up on top and making it's way to the top of the engine. These cars are never done, so add this one to the 'maybe' list.

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Richard

Supporter
Beautiful! That is definitely on my list. Luckily, I have not had that issue, so the turkey pan is a project for another day.
 
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