Megane Video Analysis - HC Brembo vs Grooved Brembo 312mm Discs

[papps]

Having recently changed up from the R26.R grooved brembo discs...


I have had a chance to try the HC Brembo discs on track now with the DS1.11 pads, and thought it would be good to see a direct comparison between the new and old discs I used....


Can you tell which you prefer - do you think either have better performance over the other?

Both clips show braking into the hairpin on Knockhill's International Layout - around 105mph (110 indicated) down to around 37mph in both cases....

 

[andybond]

2nd video seems to slow you down more, you seemed more controlled into the entry rather than a last minute squeeze of pedal and turn the car in.

 

[papps]

I don't think it was in my head after reviewing the footage - I really had so much more retardation available at the 60mph mark..... the 1st clip I really am jamming the pedal with everything I have

By that point with the HC's the temperatures must be so high that the brakes having nothing left.

The 2. clip has AD08R also, theoretically the R888-R should have better stopping power also.

My front calipers are now a nice maroon/purple colour as well, not the OEM red, @Ewan informed me that they've been getting so hot the paint has been getting cooked lol

The pedal wan't long in either case, the Motul RBF range seems to be proving its worth, literally can't get it to boil which is very encouraging.

 

[Dave_gtt]

2nd video looks to have slowed you quicker alright. Which discs were in the 2nd video?

 

[papps]

2nd video looks to have slowed you quicker alright. Which discs were in the 2nd video?

My thinking also - I had so much more stability and control towards the end of the braking zone vs number 1....

Number 2. is the grooved brembos I really didn't think the grooves would work that well during one application of the brakes - but it seems that they do!

 

[papps]

I feel that I should mention that the HC's do come back straight away once you are at the next braking zone - this overheating seems to purely be a function of contact time between the discs and the pads in each application of the brakes!

 

[andybond]

Out of curiosity how old were the Brembo HC and Grooved when you tested?

 

[papps]

The R26.R discs in clip 2. were at the end of their life - this was the last trackday I used them on, the grooves were fully worn after that session..

The HC Brembos had seen 1 2 hour tracknight and about 1000 miles of road use prior to this 2 hour session to which Clip 1 was taken from.

Both clips have good performing tyres with plenty of tread.

Fluid is RBF600 in clip 2, RBF660 in clip 1 - everything really is much the same with the analysis (well as close as you can get without a proper testing conditions etc)

 

[andybond]

I was wondering if the discs / pads needed more bedding in , but it appears not.

Plain case of spend more , better brakes I guess.

 

[Dave_gtt]

I have no track experience at all so i'm surprised i noticed the difference but it looked to me like you could have braked a little later even, seemed to slow down a bit earlier.

How much are the grooved brembos? I'm sure it's saucy.

Car looks class in the picture above, stance is perfect.:af:

 

[papps]

I have no track experience at all so i'm surprised i noticed the difference but it looked to me like you could have braked a little later even, seemed to slow down a bit earlier.

How much are the grooved brembos? I'm sure it's saucy.

Car looks class in the picture above, stance is perfect.:af:

Haha cheers mate

No you are 100% spot on with your analysis, it really looks like I could of braked a lot later in clip 2.

The issue with the grooved brembos isn't 100% cost sadly - the last set I had ended up with hariline fractures in them :ai:

nothing like this - but you get the idea lol



The grooves making them slightly weaker - and with the ultra aggressive endurance racing pads (Fedoro DS1.11) the heat takes its toll on the..

They are around £210 for the pair, vs £80 for the pair of the HC Brembos.

There's another option I'm looking into, which is these Tarox discs - they come in the OEM 312mm fitment, and would work out roughly the same price as the R26.R ones. - Front Tarox Brake Discs – Renault Megane II (02->) 1.4 16v – F2000 - TAROX Online Store



Its a difficult call, having the car's wear and tear items as cheap as possible is great as you can use the car as much as time permits, but its not a nice feeling to downgrade your braking performance lol....sure I'll figure out a nice trade off

 

[Dave_gtt]

Jesus that's a scary picture:ai:

I'm shopping for brakes too at the minute, i'm 99% going with the brembo hc's and o.e pads, but a sad pathetic part of me really loves the way the drilled or the grooved discs look, plus if the car came with the drilled from the factory i would like to keep it o.e.
Just down to convincing myself via some elaborate man maths that the extra cash is worth it:ah:

Stupid i know:ag:, plus the car is 100% standard at the minute and i swore it would stay that way, but seeing them lowered and mapped etc. means i'm getting the itch to start modding!:bc:

 

[papps]

Its not stupid at all mate - I totally get it...thats the reason I got the R26.R grooved once a few years back in the 1st place to be honest!

Have a look on renaultparts direct webpage - I find they are the best prices for OEM parts always - they have the drilled or the grooved options.

Haha the modding bug is a dangerous one, I hadn't modified a car till I got the R26, and it all kind of happened by accident by itself and I've ended up with a cage in the car LOL - its been such an amazing journey looking back really...just don't look at the bank statements :ah:

 

[DaveL485]

Interesting video. Big difference, i'd go for the second set all day long.

IMO:

Drilled discs are weak and crack from the drill holes. Avoid.
Grooved discs with lots of grooves are weak and warp really easy especially if the grooves reach the edge of the disc. Avoid.
Drilled and grooved, obviously, avoid.
Grooved like the ones you have are better, stick with those or normal flat faces.

If you're turning calipers different colours you might need to think about upgrades. Bigger discs, bigger pads, more pistons in the caliper. The faster your car gets the more braking you need from higher speeds and you start to stretch the OE specced kit. You've done a lot of work to it so maybe bear that in mind.

Also remember the extreme stresses on these components. If you think you're going to get away with hundred quid discs not cracking with regular track use think again! The heat cycling is extreme and the constant expansion and contraction will take its toll. I put good quality flat discs on the 172 (standard brakes) with EBC red stuff and im halfway through the pads and there is heat fractures all around the disc surface and a MASSIVE crack that I can now feel through the pedal in the front offside. I'm pretty brutal on brakes though I need a proper upgrade cos it scoffs brakes like a fat bird scoffs chips and the new suspension and tyres have just exposed the brakes as the weak link. Not in performance, but in "I can't take this shit any more".

I had the same problem with the 21, cracking, warping etc. I went from a single piston caliper to a 4-pot, 285mm disc to 330mm and red stuff to yellow stuff pads. Fluid to ATE Super Blue. That setup has done 4000 miles around UK and Europe, track time at Blyton, Silverstone, 4 laps of the Nordschliefe, 3 sessions on Nurburgring F1 circuit, and 2 30min sessions at Spa Francorchamps (Brutal on brakes!) and only now am I seeing some small heat fractures on the discs. I havent had a set of brakes last that long in all the time I've owned it - going on twenty years. No fade. No scary moments (not caused by brakes anyway).

Whats my point? I'm not sure, aside from you should probably get another credit card

 

[papps]

Epic post @DaveL485! thanks a lot for that

Yes, plenty of food for thought, the calipers are at a nice stage, the car is on 83k, and they've yet to be refurbed - so cost wise, its not a silly time to entertain the thought about a different calliper set up.

Its recently come to my attenion that with a little bit of custom work its possible to fit O.E 250CUP calipers to the mk2 megs, and you'd also be able to use there OEM discs - not worth ruling out at this stage I don't think

 

[andybond]

What about J Hooks ?

 

[MilosB]

I would consider some ~340mm discs, that could be more than enough of an upgrade for it as you gain more braking moment with them. and you only require a spacer to move the calipers to a bigger diameter

 

[DaveL485]

I know everyone seems to write off Hi-Spec brakes due to past (long time ago) rep, but don't. I use Billet-4 calipers and they have been fantastic and absolute stupendous value for money, I paid £305 for a pair new. Huge choice of pads too. I'm going to throw some on the back too as they now do an electronic handbrake caliper. I lucked out with discs as a Clio V6 330mm disc is a bolt on swap, so I made a hanger and voila.

 

[Ewan]

There are a few options for brake upgrade, I am thinking about going down the RS250 callipers and discs route. Potentially cheaper and larger pad area, along with a bigger disc should help with braking.

Problem I have is figuring out the custom bracket needing made for the RS250 calliper to fit. I originally thought it was just a spacer and some longer bolts needed..

 

[Brigsy]

The brembo hc's do get stupidly hot after a good session on track. The o.e drilled brembo did not seem no where near as hot, still put hairline cracks in after a few trackdays though.

I wonder how well the reyland rotor and bell setup fairs ? A few ££ mind