Brake pads.

[vlad01]

So the pads are fully worn in and ironically they are even worse at stopping at normal driving speeds. Pedal firmness is good, no noise but just doesn't stop even with full pedal effort unless you are doing 160Km/h + then they work excellent.

Having enough of this BS I contacted Brakes Direct (formally GSL rally sport) the mob that sold QFM. I told them my dilemma and that I wanted a pad like the original QFMs. They told me they had been working closely with a company called Forza and have developed a range based on the QFM compounds but next generation.

I was suggested the Forza FP3 compound was the successor to the A1-RM but better cold bite and a higher high temp range and not as aggressive on the rotors like the original QFMs.

You have that feeling the pads will be good when they come in boxes like this lol, no need to compensate with fancy box art and marketing.

The great thing is the shims pop right off with your nail, not glued on like other's I have used.

I have also booked in with my mechanic to get the front rotors changed to 027 ones, the 290mm VP series 2 rotors and I have a pair of finned calipers I got cheap on ebay on the way, so I will get him to "upgrade" the brakes while installing the pads. I am also getting him to replace the left ball joint as it's boot disintegrated years ago and it's probably stuffed now with all the dirt that's got in.

[vlad01]

Having the brakes upgraded to the 290mm size with the new pads on Thursday so to get a baseline I did a brake distance test by marking out the road and having a physical marker at the side to indicate the start of the braking. There will be probably 5m+/- of the start for reaction but I got a woeful 55m for a 100 to 0Km stop.

I will need to let them wear in over 1000km+ The white car has taken about 3000km for them to full wear in but I haven't used them heavy at all. They were literally brand new when I bought the car and also didn't stop that great but are decent now, much better than the shitbox is atm. But the white car will get VT brakes in the next few months.

[vlad01]

So had the brakes done. But the seller of the finned calipers sent me 2 left ones so couldn't use them

My mechanic improvised and used the brackets and reused the old calipers which worked but Charlescrown was right, they are bent and only contacting the pads on the very outside and inspecting the previous pads there is about a 5º taper to the pads. Normally there is always a taper but not visible by eye until the pad is metal on metal which then you can see it, but this was obvious when looking edge on.


Despite all this and not idea caliper situation the braking is amazing! Cut over 15m off the braking distance out of the box. I expect further reduction as it wears in/and I get the calipers sorted.

[Charlescrown]

I don't know how much new ones are but the go would be cast iron for performance braking.

[vlad01]

Cast iron calipers?

Been doing a little more driving around today and they have improved even more and are fantastic. I don't think I will even bother with VT upgrade on the white car and just get these pads with new front slotted rotors and call it done. The shitbox is becoming tyre limited already with 225 tyres and since the white car will remain 205mm there isn't much point going VT since it's just a work car replacement anyway.

[Charlescrown]

Of course. Did you think I meant cast iron pads? Cast calipers have a higher unsprung weight but they dont warp like alloy. My VR has VT calipers but I drive sedately and don't have problems. My track car has cast and I flog it to death.
Your brake test is very subjective with so many variables. A ADR test is probably the best but extremely expensive. I would think you as the driver will be the judge on their worth in the long run.

[vlad01]

I didn't know they made iron calipers since the 60s.
Yes I know there is variables but I used it to give me a rough initial indication, the performance of the brakes now are night and day. Absolutely a massive improvement. Currently the front pads are 2/3rds in contact and the rears are about 1/2. Once they wear in fully they will improve even more.

[Charlescrown]

It's more the co-efficient of the friction material than the contact patch. Time will tell with wear rate and performance. Yes there are still manufacturers using cast iron calipers. Isn't your car 280mm dia rotors? If so where did you get the 290mm and will they clear the calipers?

[vlad01]

The standard rotor from VB to VP S1 is 270mm and 22mm thick, the standard VP S2 was the "V8 / VL turbo" brake package, 290mm and the same 22-23mm thickness. The calipers are essentially the same except for the steel brackets which move the caliper out 10mm from center. The calipers were also finned for better stiffness and added cooling but the same geometry as the older non finned calipers.

The larger diameter just allows more leverage on the rotor with minor improvements to cooling I suppose.

[Charlescrown]

That's interesting what you say about a bracket to move the caliper out. I'v never seen one. All the ones I'v worked on bolt the caliper support to the stub axle. It must have been a quick mod to fit the bigger rotors then they changed to stub axle to suit.