Who's upgraded their rear braking system ?

[Vulcan Grey]

Well I think there is good reason to limit mass on the long end of the radius arm. Also to center mass between the front and rear wheels.

[cjtpb13]

Jonathan found this in my computer I am on travel with at the moment...

of interest...and I will have to find the article...was a discussion about caliper placement...really made no difference in force but one car manufacturer was toying with idea of being down on the bottom of the rotor for keeping weight low thus changing the CG of the car. Will try to recall and find that article too because it was a great read. Yes I have way tooo much time in the airports...lol

Christopher

[nicknick68]

Jonathan,

if interested in, TAROX is working on rear calipers, 10 pistons, WITH parking brake.

They told me they wanted to have ut ready for september, but is not ready yet, I hope it will be ready in a short time because I want to upgrade my rear brakes too.

I already put this calipers in the from (see pic) and I am going to have same calipers on the rear when ready.

Disc will be 325 or 330 mm diameter.

Nick

[Vulcan Grey]

There is an Esprit SE in Indianapolis with these brakes!

8Piston Champ Car brakes with 4 pads per caliper

[sanj]

Indeed...

[Vulcan Grey]

THanks Sanj!

I haven't actually seen pics of Neil's brakes before. I did talk with him a bunch about them last time he was in Denver.

Oh and he had talked about selling me a similar set, but then he was too busy and I found my NASCAR Brembos.

P.S. Neil must be brave... no parking brake... or did he use an in hat drum brake?

Edited December 4, 2009 by Vulcan Grey

[Jonathan]

He's got the same idea as me - chocks

I'm liking that chassis as well, looks great in white matching the car.

[sanj]

P.S. Neil must be brave... no parking brake... or did he use an in hat drum brake?

He had a pair of Wilwood spot calipers, but I can't recall if he ever installed them. Methinks not...

[karmavore]

Jon, et al,

I haven't studied the issues nearly as much as many of you have so I'd like to pose this question:

Is there anything about my Hi Specs (the PNM Kit I had fitted back in 2004!) that would preclude them being used on the rear if I had the necessary bracketry fabricated?

Also, does anyone (presumably PNM) sell a complete Hi Spec 6 pot kit for the front of the pre-Brembo cars?

[Jonathan]

Only thing I can think of Lucas is the disk thickness, if I wanted to put my AP's on the rear for example I would need a 32mm disk - you cannot really go thinner than that for that caliper because of the risk of pistons slewing and piston pop - in short there is a minimum thickness you must obide by on the caliper.

This may affect your choice of hand brake caliper and so on.

[Vulcan Grey]

Lucas,

As Jon pointed out, the PNM 4 piston calipers do no act as a parking brake, so you'd need to add a parking brake caliper.

Most parking calipers use a spacer system that would allow them to work with nearly any thickness rotor.

Also, some calipers are designed to run in a certain orientation due to differential piston bore diameter or bleed pipe orientation.

My Brembos are designed to be specific to a corner of the car. My fronts are trailing and my rears will be leading the axles. You can move a front left trailing caliper to a front right leading caliper, only if you flip the bridge pipe and bleed screws, but at least the pistons will be in the right orientation for the rotor sweep... get it.

Not sure if the PNM have the location specificness...

[karmavore]

Lucas,

... get it.

Got it. Thanks Travis.

I'm going to pull the trigger on a full Hi Spec upgrade from PNM. For $3K (6 pot/320mm 2-pc F and 4 pot/300mm 1-pc R w/hand brake) you can't go wrong, not for the type of driving I *mainly* do.

[Vulcan Grey]

I was waiting to get a quote back from the guy who I bought my brembos from.

He wasn't able to give me the same price that he gave me years ago, but it may still not be bad.

He might be in a good mood since he was building the car that won the championship, last time I talked to him was just before the final race.

[Jonathan]

Found it Jonathan...rather interesting...right up your alley

ABS dynamics with regards to brake upgrades

Might have come to haunt me this one.

Tried it out late this evening on my way to a friends - ABS chips in very harshly.

Thing is my tyres are brand spanking new, roads arn't exactly warm either (tyre temp not over 20c/68f - ambient 4c/40f) so not ideal to say the least.

If you ease the brakes OMG the car stops like hitting a wall - it's at least twice the power for the same effort.

However if you emergency brake the ABS just goes nuts and the solenoids just open robbing you of any power - I think this is more to do with the deceleration than locking.

What is further strange is that if you get the ABS to cut in, any further braking ~10secs after goes straight into ABS mode which is quite frightning.

I'm hoping this is part worst case scenario, cold, new tyres, low grip coef.

The force of the fronts alone is staggering - very might night/day (when the ABS leaves it alone !!!)

[Vulcan Grey]

don't forget that a stiffer suspension also can effect ABS... My Acura has very good AS, but I added very stiff suspension, and over bumpy pavement (especially in the wet) the ABS will freak out, lock up the brakes and then suddenly quit braking in an attempt to prevent the wheels from locking.

It would definitely be safer with no ABS in that case.

[saggitarius]

A short question from a novice when it comes to Lotus brake systems:

If you fit a bigger brake caliper on an S4/V8 without a handbrake mechanism at the rear and plan to fit a separate (spot) caliper for the handbrake, where do you fit the spot?

There is as far as I can figure out only one set of bolt holes in the hub carrier and wouldn't it be difficult to fit the handbrake caliper in the same place?

Thanks for a great forum and good input.

[Vulcan Grey]

Well you ca either do a leading rear caliper with a bracket that mounts to the rear swing arm, and a trailing parking caliper, like this.

http://picasaweb.google.com/lotusse/LotusAPRacingBrakes#

Or you can do a trailing rear caliper with a leading parking caliper on a bracket, like this.

http://picasaweb.google.com/lotusse/LotusWilwoodBrakes#

Edited March 12, 2010 by Vulcan Grey

[Jonathan]

I'm planning on the former - the S300/X180 had longer bolts through the end of the radius / swing arm into the caliper mounting, fairly easy to do.

[Simon350S]

That AP setup looks serious! I likey!

[Vulcan Grey]

That AP setup looks serious! I likey!

The AP is nice, very good on the track. I'm modeling mine after those.

here's what I'm doing

Brembo Racing 4 piston monoblock fronts with vented titanium pistons, and rotor is 328mmx35mm

The rear are Brembo Racing 4 piston bolted calipers with vented titanium pistons and a 313mmx25.4mm rotor.

[Simon350S]

Nice one Travis!

Thats a lot of $$$$ sitting on your carpet! Can't wait to see them in place.

[Vulcan Grey]

you might be surprised....

That is a $12,000 brake system...

but that's not what I paid!

[Simon350S]

Can you get another set? I'd love them on my car!

Can you supprise me by taking 2 zeros off the price please?

[Vulcan Grey]

Well I paid 1 zero less...

but I spoke to my source recently, and he said that he couldn't give me that same price anymore... but he would try and figure out how much.

[saggitarius]

I agree with the formers here: That's one serious braking system. It looks $$$ and with that brand and those dimensions it's going to slow the car down like nothing else. Real beauties!!

And thanks all for the really helpful advice. This forum and it's members are invaluable.