Front Brake calipers

[Tabcon]

Besides the direct fit Toyota option, does anyone know of any other direct or close fit with some modification options for calipers made by companies such as AP, Brembo or Wilwood?

 

[Grantura_MKI]

Check out Daid/Gerald TVR, as they have some 4 pot calipers that may suit you.

 

[Grantura_MKI]

Sorry about that, it is David/Gerald TVR.

 

[MadMarx]

Why using different brake calipers as with the stock ones and good brake pads you can almost brake out everybody?

Cheers
Chris

 

[Monkeywrench]

Why using different brake calipers as with the stock ones and good brake pads you can almost brake out everybody?

Cheers
Chris

Only possible if everyone who you run against has to run stock brake calipers or that driver is not good. :wink:

There are really better way options out there, I just don't know of any that are a direct fit. No one in the States (be it vintage or SCCA) can run anything but the stock, Toyota, or Jaguar (SCCA) calipers. I have however seen some west coast vintage cars (a TR6 and the TR250K) with Outlaw calipers.

 

[MadMarx]

We had in our racing group illegal cars with different brake system but non of them could outbrake a well driven TR with stock brake.

From time to time we run with modern cars, some of them can brake later, caused by slick tires, but I really don't see much advantage of other brakes.

A good brake bias is the key. Much balance to the rear makes brake performance.

Cheers
Chris

 

[Monkeywrench]

We've seen the same thing. The only cars that we run against that can outbrake the TR4 consistently are the very best Porsche 356s in the country (300lbs lighter, 4 wheel disc brakes, and superior weight distribution) and Super 7s (950lbs lighter).

As long as the rotating weight, vehicle weight, and the driver are all equal, a good aftermarket caliper will always win.

Yes you are still limited by the tire for braking performance, but the big thing you are getting with the aftermarket caliper is stiffness and the ability to modulate at the limit better (for several reasons).

They also have the ability to absorb more heat. Most of the vintage races are too short that this isn't a problem, but if we ran SCCA race lengths (40 minutes), it would be (the SCCA TR6 racers have this problem with vented Jaguar brakes). Some tracks in a TR4 you're hauling down from about 136mph to 50mph. That makes for a lot of heat.

Lastly, they're cheaper in the long run. You can change pads in minutes and everything you need to rebuild one is readily available, cheap, and of known good quality.

Agree about brake bias.

 

[MadMarx]

Our racing group has 30 min races, 60 min and 300-400 km races.
So we have all kinds of length which makes life not easy for the brake, especially races on the Nordschleife.

Sure a modern brake can stand more heat as the rotors are bigger or vented and the brake pads are larger. Maybe modulating of the brake is better too the difference is nor large and most vintage drivers won't feel much difference (BTW once Marc Basseng LEMS driver did race a TR3 and was surprised about the good brakes of that car).

After I installed wings to my pads the overheating was gone and the pads did last longer. A little fiddle with the securing pins but if you only change pads once a season that is no problem.

For the TR brakes I would say there are no cheaper parts than for these cars, incl. the pads.

Sorry that my car doesn't reach 136 mph, mine does reach on the longest straight 129 mph.

I've heard that the US 356 Porsches are very fast. In Europe the don't have that much power. In most cases I can outperform 911 Porsches and 356 from years 55 - 65.

Funny that you mention the Super 7s. I had some fun with them and didn't found them late braking...but they were historic Super 7 with Yokohama tires.
The Caterhams are a lot faster:
https://picasaweb.google.com/tr4racing/TR4Racing#5524885186093538722

Cheers
Chris

 

[Monkeywrench]

I agree, it's a waste for most, but the fast guys have enough talent that it would make a difference.

In SVRA's run groups the TR4 is one of the heavier cars (granted it has one of the largest displacement engines in its run group). The only cars I can think of that have to weigh more are Volvo P1800s, Chevy Corvairs, and Austin Healeys.

From what I've read, the fastest Porsche 356's over here are pushing about 165-170bhp and weigh 1710lbs without driver. Their performance seems to agree with that figure. They're virtually unbeatable at anything other than a horsepower track. Despite their age, the chassis has much more potential than a TR. It doesn't hurt that the fast ones are excellently driven.

There are a few 1500cc Super 7's in our run groups. I'm not sure why that is. 1500cc, dual webers, and a min. weight of 1175lbs. Of the ones the Triumph has run against, we have beaten all but two of them.

Theoretically the fastest cars we run against should be the Ginetta G4s. They're pretty much of equal spec to the Super 7s, but the full body work allows them to have more top end. They're essentially sport racers.

 

[Tabcon]

Problem solved!


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[MadMarx]

Would be interesting to find out what does perform better:

 

[Hap Waldrop]

FWIW, this is not allowed in SCCA production classes on fornt brakes and in most vintage groups with production sport cars. SCCA production calsses do allow alternate rear disc brakes for car that came with drum brakes, the rule is pretty basic, no bigger rotor than used on the front and the caliper is open, on the SCCA Spridget we used a hat style rotor and small single opposing pistons Willwood calipers.

 

[Tabcon]

Chris, I never tested the brakes before making the modification, so I don't have any benchmark to judge how much improvement may be realized over stock. The one thing I do know, is that these calipers weigh considerably less than the stock ones or the after market Toyota caliper upgrade.

There's an article over at The Vintage Triumph Register about using the Toyota calipers as a replacement for the TR4's 2 piston caliper. Here is an excerpt from it:

<span style="font-style: italic">All tests were performed with a newly rebuilt master cylinder, using DOT 5 brake fluid. The variations tested and the results of the testing were:

1. Early (prior to metric calipers, Girling 16PB) stock configuration with semi metallic pads, composite shoes and 0.70" rear wheel cylinders: 262 feet with a standard deviation of 19; 6 data points, tossed out both the minimum and maximum measurements.

2. Toyota front calipers with semi metallic pads, composite shoes: 243 feet with a standard deviation of 9; 8 data points, tossed out minimum and maximum.

3. Toyota front calipers with semi metallic pads, composite shoes with a 7/8 inch rear wheel cylinder: 215 feet with a standard deviation of 9; 9 data points, tossed out minimum and maximum. </span>

Yea Hap I knew about the SCCA production class rules but vintage rules change so much from region to region, I haven't really looked into it yet, but I'm sure it's most likely a no no in most of these events as well. The rotor is a stock size and since the Wilwood's bolt right on, swapping then out with stock calipers would only take a few minutes.

It will be interesting to see if the Wilwood calipers work any better than the Toyota conversion.

 

[MadMarx]

Okay, I see.
You are following a different way of tuning.

My goal is to get the max performance out of the stock parts. I refuse to use modern equipment as good as I can.
Only where reliability is needed like for rods or pistons I use modern parts.

Would be interesting to know how your car would perform compared with mine.

My brake performance is around 0.8-1.1G.


Cheers
Chris

 

[blangtr6]

one thing that hasn't made this thread - if you get the right caliper / rotor combo, you can shave some serious _unsprung weight_ from the car.

all other points about checking the rules apply though, so not for SCCA Prod classes and certainly not for vintage. Now SCCA GT rules would allow them, but I don't think any Triumph would be considered good candidates for GT.

Chris, I admire your "keep it vintage" attitude. It's really easy to start wanting to fiddle with the equipment (and rules) and totally change the character of vintage racing. Heck, a lot of folks out there would be WAY better off spending thier development $$$ on seat time!! Then we'd have more vintage cars actually running at events.

rml

 

[Hap Waldrop]

Heck, a lot of folks out there would be WAY better off spending thier development $$$ on seat time!! Then we'd have more vintage cars actually running at events.

rml

No truer words have ever been spoken, I got to drive a $85K SCCA H-prod Huffaker Bugeye for season, no doubt the trickiest Bugeye race car ever build, while we did have our handling issues with this car, we could only beat another vetran Spridget drive with a much less tricker chassis, a driver and his talent mean alot in the "fast" equation.

Here's a funny story, I had a guy call me numerous times a few years ago, he wanted to build a HP SCCA Sprite for his wife to race in the SCCA, the guy was top notch CNC machinist and had the abilty to make all kinds of stuff incluidng about anyhting he could dream up to make out of titanium. He loved to tell me how he was going to put all the trick stuff on his wife's chassis and they were go out show everybody how it's done. I giggled at this and then introduced him to the real world, I told , here's what going to tick you off, you going to go to national SCCA race and run up against folks like Tony Drum,and Randy Canfield, Tony is 70 now and Randy is 80,,and there cars are far from being considerd trick by todays standards, heck Tony probably only washed his car real good about every 5 years , and these old geezers will probaby lap your wife one or more times in a national race, then only thing left for you to do is trick out the driver for that level of performance, I have not heard from that guy in long while

 

[Monkeywrench]

all other points about checking the rules apply though, so not for SCCA Prod classes and certainly not for vintage.

Bob, did you take a look at those two 6 cylinder powered Triumphs from the PNW at Watkins Glen in 2008? :wink:

I've also seen pictures of some of the VARA Triumphs with vented roters and different calipers up front. VARA does things a bit differently though ("cheater" RDOTS, no min. weight, non-flared composite body parts, and hard tonneau covers to name a few)

 

[MadMarx]

...Heck, a lot of folks out there would be WAY better off spending thier development $$$ on seat time!! Then we'd have more vintage cars actually running at events.

I would sign that.
January 2010 I did a drivers practice in the snow and ice to learn drifting and I chose Walter Roehrl as instructor.

He learned my how to drive sideways and chased away any fear of the car not going straight.
And it really boosted my driving. I became much quicker and I lost any fear about the rear end coming out.

So seat time is much more important than any horse power....

Cheers
Chris

 

[dougie]

<span style="font-weight: bold">
Bob, did you take a look at those two 6 cylinder powered Triumphs from the PNW at Watkins Glen in 2008? :wink:</span>

The unspoken policy here in the PNW is "don't ask, don't tell". The biggest cheaters are the Germans though. The Porsche's and BMW's could run in most big-bore grids............it's gotten a little out of hand.

 

[MadMarx]

.... The biggest cheaters are the Germans though.....

I heard that!