AK Motorsports Gallardo front calipers on M3?

[BLuRRYM3]

Are there any reviews or testimonials for this product? Also, what is the difference between the "basic" and "full" kit? I'm not at my comp right now, so I can't compare them side to side on my phone.

[Rat3d ///M]

Originally Posted by BLuRRYM3

Are there any reviews or testimonials for this product? Also, what is the difference between the "basic" and "full" kit? I'm not at my comp right now, so I can't compare them side to side on my phone.

As of now, there aren't any reviews of this kit, but I have been in talks with Albert over the last couple months and am working out a deal with him in which I will be providing an install DIY, as well as a review of street (Autobahn), and track (Neurburgring/Hockenheimring) use, all with pictures and video. We are in talks of me getting my kit in January (last time I spoke with him), and the DIY should be done by late January, with the review portion done by May.

And to my knowledge, the basic kit is just pads, calipers and mounting hardware/brackets, and the full kit includes rotors and brake lines. I could be wrong though.

[albertracing]

Originally Posted by BLuRRYM3

what is the difference between the "basic" and "full" kit? I'm not at my comp right now, so I can't compare them side to side on my phone.

Basic kit is
- calipers
- adapters + mounting screws

Full kit is
- calipers
- adapters + mounting screws
- pads
- stainless steel brake lines

Both kits are to be used with OEM brake disc.

[zero2sixtyZ]

Originally Posted by ||||||||||

As of now, there aren't any reviews of this kit, but I have been in talks with Albert over the last couple months and am working out a deal with him in which I will be providing an install DIY, as well as a review of street (Autobahn), and track (Neurburgring/Hockenheimring) use, all with pictures and video. We are in talks of me getting my kit in January (last time I spoke with him), and the DIY should be done by late January, with the review portion done by May.

And to my knowledge, the basic kit is just pads, calipers and mounting hardware/brackets, and the full kit includes rotors and brake lines. I could be wrong though.

In for a review, as I'm interested in the E92 Non-M kit.

[jritt@essex]

Did anyone ever come up with the accurate piston sizes for the calipers in this kit? The numbers posted before seem to have some 'maybe' and 'I think' attached to them. That's nobody's fault obviously, but that makes it pretty darn tough to perform a precise mathematical analysis. With accurate piston sizes I can calculate the impact on brake bias for you guys, assuming the OEM master cylinder are rear brakes are retained. My hunch is that the brake torque on the front will be over-amplified (which is typical when you bolt on calipers from a different application), but you don't know 'til you know. Thanks.

[The HACK]

Originally Posted by apecush

did some quick calcs re: piston area.

OEM w/60mm front, 46mm rear pistons = 2827mm2 (f) / 1661mm2 (r)
Lambo/porsche setup = 2839 mm2 (f) / 1322mm2 (r)

Basically, if you go with this kit, you will move the bias to the front. Based on the piston area, there would be no bias change using the front kit only.

Edit:
Lambo/Porsche calc is wrong, only calculated half of each calliper...do'h.

So no, front kit alone is probably not a great idea.

If the above number is correct, it would be irresponsible for said vendor to try and sell this on ANY car, street or track. That rear piston area is off by 20% or more.

Unless the vendor can supply actual brake piston specs, I wouldn't touch it with a thousand foot pole. Without actual OE piston size calculation and calculation for said kit, no one should even contemplate putting it on any car, IMO.

[albertracing]

Originally Posted by The HACK

If the above number is correct, it would be irresponsible for said vendor to try and sell this on ANY car, street or track. That rear piston area is off by 20% or more.

Unless the vendor can supply actual brake piston specs, I wouldn't touch it with a thousand foot pole. Without actual OE piston size calculation and calculation for said kit, no one should even contemplate putting it on any car, IMO.

Originally Posted by albertracing

Just to cut the discussion we will be using newer Cayenne brake carpels that have 4 x 32 mm pistons from now on. The old setup worked just fine but ... "customer is always right".

The news setup will have piston area f/r balance almost the same as stock

OEM w/60mm front, 46mm rear pistons = 2827mm2 (f) / 1661mm2 (r) - f/r balance 0.588
Lambo/new porsche setup = 5677 mm2 (f) / 3215 mm2 (r) - f/r balance 0.566

This is what I have posted on November 16th. Here are all the data you need.

Front is 4 x 28 mm+ 4 x 32 mm pistons, rear is 4 x 32 mm pistons. Please read the previous posts before posting comments.

[The HACK]

Originally Posted by albertracing

This is what I have posted on November 16th. Here are all the data you need.

Front is 4 x 28 mm+ 4 x 32 mm pistons, rear is 4 x 32 mm pistons. Please read the previous posts before posting comments.

Woa. IF what you said is correct, I would NEVER buy this kit. The way you've presented your calculations, it would seem to the layman that the overall piston area is 100% more than OE piston area. Which would lead to a master cylinder that divides pedal pressure in half, thus the pedal would almost always go all the way to the floor before ANY tangible piston pressure is felt.

I mean, that is a HUGE increase in overall piston area. I once installed a kit in another car that was merely a 10% increase in piston size, and we chased a soft pedal that couldn't activate ABS forever until someone pointed out to us that our piston sizes were bigger than OE. That was 10% increase in piston size.

If what you calculated is correct, that's nearly 100% increase in piston area.

(Of course, I could also simply point out that piston area as compared to master cylinder size ratio is only calculated per clamping side, thus saving you the effort to try and explain why a ~100% increase in OVERALL piston area isn't comparable, but an actual 0.1% DECREASE in piston to master cylinder area.)

But I'm just your average intarweb poster. If I know more about how to properly calculate piston size to master cylinder ratio...well...I'll leave the others to draw the conclusion.

What I WILL point out is, despite the fact that I am no where near the brake expert you are, that this particular set-up, despite what I pointed out in fine print, effectively shift brake bias up front, because the front caliper ratio to master cylinder compared to OE is 0.4% larger, but the rear caliper ratio to master cylinder compared to OE is 4.3% smaller, meaning the fluid is going to want to take the easier path of the two and supply a ~5% higher bias toward the front. Now, for street applications, where all you want the caliper to do is to look good? No big deal. Since BMW already dialed in more front bias than necessary, intending for street use on the OE system. If this was a properly engineered, 4 wheel upgrade? That front caliper piston area needs to be smaller than OE, while the rear remain the same as OE. Various racing team data points to the fact that the rears aren't doing much and a bias shift of 5-10% to the rear actually improves brake performance in repeated applications.

Like I said, I'm just your average intarweb poster. I'll leave the actual brake engineering to the experts.

[Rat3d ///M]

Here we go again

Does anyone happen to know the piston size(s) of the Brembo and Stoptech 6 piston kits for our cars? I searched, but couldn't find anything. Just to prove a point, I would be curious to see how much of a surface area increase the Brembo 6 piston kits are over stock. I would bet money that it is much more than the 10% increase that caused issues in the aforementioned vehicle, if not closer to a 100% increase like this setup is

Regardless of what the numbers say on paper, this isn't the first time this setup has been used. People have had brackets fabricated for Gallardo/R8 calipers on the E9x M3 before as one off setups. I know a guy locally that has done it, and he tracks the car with no issues with pedal pressure whatsoever (quite the opposite actually). All Albert is doing is trying to mass produce a system that has already been toyed with. We won't know if it works, until someone buys it, tries it, and reviews it, so why argue about what numbers say until we know for sure?

[Rat3d ///M]

Sorry for making promises to everyone that I can't keep, but I've decided to go a different route with the M3, so there won't be a review of these in May. Thank you Albert, for offering to work with me and being so willing to make a deal to help me out. I never doubted (and still don't) that this setup will do very well on the street, and will perform exceptionally well on the track, but I came across a deal for some used Stoptechs which I was unable to pass up.

Hopefully the coverage this thread received will help promote this guys business and get some buyers for this kit. I would like to see this kit marketed in the US and on some ///M's in the near future.

[opihi5]

Reviving this post. Any updates?

[dj_dub]

Originally Posted by opihi5

Reviving this post. Any updates?

Look a few threads down...there's going to be a couple of reviews coming shortly.

http://www.m3post.com/forums/showthr...=632273&page=7

[opihi5]

Originally Posted by dj_dub

Look a few threads down...there's going to be a couple of reviews coming shortly.

http://www.m3post.com/forums/showthr...=632273&page=7

Thanks, not sure why people are making a big deal over this. Many WRX owners slap ctsv big brakes on and claim no problems.

[sebaflex]

just looked them up, they seem to be out of business.

[randrews15]

Looks like the link is no longer active...makes me wonder if something wasn't quite right with it.

[roastbeef]

These kits have pretty much turned out to be garbage.

[shimmy23]

Originally Posted by roastbeef

These kits have pretty much turned out to be garbage.

How so?

[roastbeef]

Originally Posted by shimmy23

How so?

All of these aftermarket caliper retrofits have their problems. Some are fine, some won't bolt on, some don't have good pad sweep.