E34 M5 Big Brake Kit -Any experience?

[tonym427]

I'm trying to see if anyone has any experience with the e34 m5 US rotor and caliper upgrade for the e24.

Turner Upgrade (http://www.turnermotorsport.com/p-180855-e34-m5-315mm-front-brake-upgrade-for-e28-528e535im5.aspx)

Is it a worthwhile upgrade?
Where is the best pricing for the calipers?
Should you also upgrade to the e32 master cylinder?

Also what route did you take with the rears?

Thanks

[RSheiman]

At the risk of getting a heap of crap.....when I had the same idea, someone on this forum who does brakes for a living told me the E24 system was more than ok for daily driving and I should do myself a favor and rebuild the calipers and get SS brake lines. That's what I did and could not be happier. Yes the upgrade will get you that extra stopping power in a bad situation, but you have to decide if that's your mindset or not. If track, then upgrade. Plenty of posts on what to use. Most will tell you that since in Ca, find the parts at a pick and pull if you can, incl mounting brackets.

[daniels635turbo]

I have the m5 rear calipers and e32 750iL front calipers. Put the master cylinder from the 750iL in. Also have braided stainless lines. Works awesome. Correct the e24 system is fine with braided lines, I kept warping rotors. Biggest difference is the vented rears. I also installed a brake bias adjuster.

[tonym427]

I see. Thanks for the help RSheiman. I might consider finding the upgrade parts as my rotors are on their way out and my calipers need a rebuild. Thanks for the input daniels

[mauryc]

Just completed this on my 88'. I went with e34 540 front and rears - full rebuild, stainless lines, new e32 mc, etc. I'll also put my flame suit on, but in everyday driving I can tell little if any difference. I don't track or drive her hard so my experience is limited. It is nice to know I've got plenty of braking power if I need it.......

just my .02, Maury

[Greg330Ci]

I'm skeptical about the merits of big brake kits for street driven cars in the US. Different story if you track your car or make repeated stops from very high speeds (unlikely here in the US)where you would encounter fade. I think the standard BMW brakes are more than up to the task of spirited street driving here. Better to invest in SS brake lines, good pads and fluid.

[bkats]

I third, or fourth , or whatever, just upgrading the lines and pads. The E24 isn't THAT heavy, and really isn't THAT fast. I find that the hydraulic system makes it feel like I'm not stopping fast enough, but ultimately, I can't out-drive my brakes.

[Dash01]

If big brakes = bigger heavier calipers, rotors, etc., then big brakes also = worse handling.

The more unsprung wheel weight, the worse the handling and the less nimble the car.

[WWW89E24]

I am going to document my Amazon procured miss-priced big brake kit in an upcoming post. All of the pieces are sitting here in my office. At this point, I know one thing......they are all VERY heavy. 750il front and 540i rears. Having hauled these things around, I am increasingly worried about unsprung weight and rotating mass. I saved the following from a post by Mr. Zenmervolt on another forum:

"Actually, what you're talking about is rotating mass, not unsprung weight. Rotating mass must be accelerated/decelerated every time the speed changes, and it's harder to accelerate the rotating mass. Since most rotating mass (aside from the engine and the tranny) is unsprung weight (half-shafts, wheels, brake rotors), a reduction in unsprung weight generally entails a reduction in rotating mass, which helps acceleration. It is rotating mass that is roughly 3 times harder to accelerate than normal weight. Plain old unsprung weight is not any harder to accelerate. Basically, rotating mass must be accelerated twice every time the car speeds up, it must be accelerated linearly (in the direction of the vehicle's travel) and rotationally (in the direction of its spin). As for a reduction in unsprung weight independent from rotating mass, this generally improves the suspension's ability to work properly. Unsprung weight contributes to inertia in the suspension, which in turn affects the geometry assumed by the suspension."


I think that means when I run out of gas, I'll roll farther.......

[daniels635turbo]

How's the parts sourcing coming along?

[WWW89E24]

How's the parts sourcing coming along?

All done.....just under $300

http://www.bimmerforums.com/forum/showthread.php?2167078-Amazon-Scavenger-Hunt-Big-Breaks-%28pun-intended%29

[daniels635turbo]

And you didn't have coupons either!

[tschultz]

Adding E34 rear brakes, even the unvented style adds a dramatic performance difference. I'd also suggest keeping the stock master as I like the additional pedal travel/feel.

[pthm]

just thought about a 540 at the junk yard and then you post this. all new parts and what not . . . . curse you

[chevale]

I do have e34M5 (US) brakes all around + stainless steel lines and standard MC.
While overall brake feeling is more solid, if I've been asked today I would went with 740 front and 540 rear kit: almost the same diameter but parts significantly cheaper and more available.
Plus, some of my nice 16" rims cannot clear M5 brakes, and others can barely be fit with almost no clearance .

[Sprocket]

Mine was converted prior to me. I have the original rotors and they are much lighter that the current (E32/E34) set. The size difference is remarkable.

The brakes feel great, but I don't know how it felt before.... Wheel size is a consideration, as mentioned above. I don't think my spare (original) will actually fit on the the front anymore. Yes, I need a new spare wheel...