Ralliart brake ideas?

[BST50N]

which QFM pads Nicholas?

I'm not sure which ones mate - they aren't the full racing ones however. The guy from Rallysport (i think) where I bought them said unless I was tracking the car a lot I shouldn't get those, as they would chew the rotors up in no time. Result - well I'm not sure yet. I feel that I need to apply a bit more pressure to get them to bite, but they bite a bit harder when they do. I wouldn't say it is a huge improvement in performance, but maybe a bit. I was hoping for a bit more actually, but still not too bad. Probably a good upgrade if you aren't going to be tracking it and just want a bit more stopping power.

Now I don't know how many of you guys have seen this ( I know some guys from here have been posting on the thread) but check THIS out:

http://www.clubralliart.com/showthread.php?t=3952

Now this is a good upgrade for the RA, and the price is great too!

[JustinR]

Yummmmm! Wish i had the $$$ though..

[BST50N]

Oh yeah looks amazing - price is great, but shipping would be a killer to land here.

[billyboy]

[quote:1c7062b968=sleeper]which QFM pads Nicholas?[/quote:1c7062b968] Im not sure which ones mate - they arent the full racing ones however. The guy from Rallysport (i think) where I bought them said unless I was tracking the car a lot I shouldnt get those, as they would chew the rotors up in no time. Result - well Im not sure yet. I feel that I need to apply a bit more pressure to get them to bite, but they bite a bit harder when they do. I wouldnt say it is a huge improvement in performance, but maybe a bit. I was hoping for a bit more actually, but still not too bad. Probably a good upgrade if you arent going to be tracking it and just want a bit more stopping power. Now I dont know how many of you guys have seen this ( I know some guys from here have been posting on the thread) but check THIS out: http://www.clubralliart.com/showthread.php?t=3952 Now this is a good upgrade for the RA, and the price is great too!

Probably got the HPX pads?

Got these on my RA (fronts only, still have oem on rear) had them for a while now & havent really noticed that need to apply more pressure than did before, but yes agree slight better stopping power than oem.

Only gripe is they've developed an intermittent squeek

[sleeper]

yeah, theres QMD and then theres QMD, the hot ones are a vast improvement, like i said i have REMSAS atm, stop on a dime with the oem rotors and a 600 temp fluid, even on the 1/4 mile.

[BST50N]

Probably got the HPX pads? Got these on my RA (fronts only, still have oem on rear) had them for a while now & havent really noticed that need to apply more pressure than did before, but yes agree slight better stopping power than oem. Only gripe is theyve developed an intermittent squeek

Yeah now you mention it I did get the HPX pads I think. They are noisier than stock too - i can hear a very slight sound when I'm driving, like they are still contacting the rotor. I'm pretty sure most pads do this, but I can hear these ones more. I feel that the stock ones sort of 'took up' slightly earlier, but these grab more with a little extra pressure. Its not night and day however - maybe 20% improvement tops (bum dyno).

yeah, theres QMD and then theres QMD, the hot ones are a vast improvement, like i said i have REMSAS atm, stop on a dime with the oem rotors and a 600 temp fluid, even on the 1/4 mile.

Hey Steve, what do you mean by QMD? My pads are QFM (i think its Queensland Friction Materials.). I got high temp fluid also, but yeah not huge difference.

[sleeper]

oh, sorry, yeah, i meant QFM.

QMD was a different thread, lol. soz.

HPX arent a much bigger temp rating than OEM

QFM A1RM are the go if u want to make a difference.

similar to REMSA specs, slightly less

[BST50N]

oh, sorry, yeah, i meant QFM. QMD was a different thread, lol. soz. HPX arent a much bigger temp rating than OEM QFM A1RM are the go if u want to make a difference. similar to REMSA specs, slightly less

How long have you been running the REMSA pads? Have you noticed any rotor wear? Only reason I didn't go with the others was I was advised my rotors would be chewed up very

[sleeper]

rotor wear?
i`m afraid to look

[El-Diablo]

I'm doing a bit more research been reading the Evolution net thread on ra brakes mark 2 but it doesn't overly fill me with confidence.

I just want to remind everyone that Brakes are not cosmetic they are a safety item and not for backyard players and wannabe's designing kits. A set of willwood radial mount calipers is around $375 each in the same spec as evo x brembo. What is then required is to get the correct dimensions to have a proper mounting bracket made.

I am trying to get the technical details and will post something up when I have the data.

Drilling and machining existing mounting points can seriously compromise the design integrity of the system not to mention the legal and insurance consequences if something goes wrong.


There is no such thing as CHEAP brakes and you are kidding yourself if you think that is the case.

Simply put if you want cheap brakes what we need to do is buy the Brembo GT kit measure the mounting brackets and duplicate them then any caliper with the same mounting details will fit. this would cost one of us around $3200

Alternatively I need the dimensions of the standard RA spindle and the evo spindle to get a bracket properly designed.

I've spent over 20 years in automotive for one of the big three and some of the brake comments I see are quite frankly frightening.

Most recently was the set where the pads overhang the edge of the disk to the point where they are not swept cleanly this could potentially result in a step in the pad material some heat some cracking some loose material between the pad and the wheel and kiss your ass goodbye or at the least a potentially expensive repair.

So please unless its engineered for the car from a reputable manufacturer who is willing to back that design/combination steer clear.

[BST50N]

Rob I think you raise some good points here. When you refer to the pad overhang are you talking about this pic:



This is a pic from the newest Ralliart BBK kit that I posted about earlier. You can see that it appears there is a small amount of pad contact in the middle of the pad. If you look at the shape of the pad it seems like the diameter of the rotor isn't quite matching that of the pad. It doesn't look like a lot, but does that matter? I don't know I'm not an engineer. Whats the main danger of a bit of the pad cracking and falling off? It going between the pad and rotor, and not allowing full contact, and therefore not getting full braking power?

With regards to drilling the spindle mounts I agree this is not the best idea. It also looks like they've machined a good few mm off the back of the caliper to allow it to match up with the RA mount:


Again, i don't know if taking this much off will have any detrimental effects. I think it would be better if they machined the caliper to have the same 'ears' (outside edges of the bolt holes) as the spindle, so the machined bits sort of wrapped around them, and if they fit tightly would transfer some of that torque onto the calipers and maybe less shear on the mounting bolts? Just an idea.

Also instead of drilling out the spindle holes, why not helicoil the calipers to accept a 12mm bolt? If this size bolt is enough take the forces of the stock brakes, why wouldn't it be enough for these?

[El-Diablo]

I'm not sure that's the same picture but its a similar issue the contact area should sweep the whole pad so the pad wears evenly a thin ridge on the pad would be prone to cracking.

In regards to comments like it's only 2 mm extra diameter it is far more complicated. If for example the thickness of the lug is 10 mm over the diameter of the hole you have effectively reduce the strength of the lug by ten percent while at the same time increasing the load on the mounting point by introducing a far higher brake torque. If you use a pistol drill to drill out the holes you risk overheating effecting the properties of the material.

A larger diameter bolt is significantly stronger to take the extra shear and tensile forces, the caliper is much further outwards so the moment created by the brake force is now further out and exponentially greater than the original forces involved the same with the transferred torque.

If this is a six pot caliper depending on the volume of the pistons you are also compromising the master cylinder the standard evo x uses a larger volume master cylinder.

The difference between the cheapest BBK and the most expensive is not that great considering. You can pick up a properly engineered stoptech kit for around $2200. Or go all the way for a Brembo with 355 rotors for $3200. Even the cheapest home made type sets are over $1000 mostly around the $1200 mark.

Save your money a bit longer it might just save your life or someone elses.

The way to do it cheaply is to engineer it properly appropriate wilwood calipers are $375 each brackets would be around $100 to manufacture.

But it involves getting either the spindles form an ra and an evo putting them on a coordinate measuring machine and designing the parts to suit based on the manufacturers engineering drawings and recommendations. Then at the very least getting an engineer to do the calculations to verify the assemblies.

[BST50N]

In regards to comments like its only 2 mm extra diameter it is far more complicated. If for example the thickness of the lug is 10 mm over the diameter of the hole you have effectively reduce the strength of the lug by ten percent while at the same time increasing the load on the mounting point by introducing a far higher brake torque. If you use a pistol drill to drill out the holes you risk overheating effecting the properties of the material. A larger diameter bolt is significantly stronger to take the extra shear and tensile forces, the caliper is much further outwards so the moment created by the brake force is now further out and exponentially greater than the original forces involved the same with the transferred torque.

Hmmm good point, I didn't think of this. That bigger caliper is going to be like having a longer lever point, combined with larger holes in the spindles, less material, and quite possibly bolts that aren't drilled entirely straight! I can see how this might be an issue.

The way to do it cheaply is to engineer it properly appropriate wilwood calipers are $375 each brackets would be around $100 to manufacture.

But it involves getting either the spindles form an ra and an evo putting them on a coordinate measuring machine and designing the parts to suit based on the manufacturers engineering drawings and recommendations. Then at the very least getting an engineer to do the calculations to verify the assemblies.

So pretty much getting adaptor plates made up that would bring out the mounting points for the calipers to the same diameter as the evo x and run the evo rotors? Wouldn't it just be easier to use the Evo X spindles ?

[El-Diablo]

The only thing im not sure of is if the evo x has the same track as the ralliart. But theroetically yes evo x spindles will work and just use evo brakes or an evo upgrade kit.

[parralegend]

http://clubcj.net/viewtopic.php?p=341861#341861 have a read of this as it will go through my experience with the kit in question