Brake interchangeability 4.6is on a 3.0i

[RFaber]

I was wondering if anyone has any experience with putting the bigger (356mm) rotors, calipers and pads from a 4.6is onto a 3.0i equipped X5?
is it possible with just rotors, calipers and pads? or do i need the spindles and any other parts?? I have a line on a wrecked (engine only) 4.6is and was thinking if i could get the brakes ... ... ??? i would like to improve my braking performance. I was also wondering if i could still use my 18 inch stock star 69 pattern wheels??
thanx

[TerminatorX5]

the rear rotors on the iS are vented... the rotors are bigger to begin with, so the 18" wheels are the bare minimum that you will be able to pull over those rotors...

Mechanically, you should be able to put the bigger rotors and the calipers, i am not sure about the hydraulics though... you should run the real OEM to cross reference the brake systems between the regular 3.0 and the 4.6 and see if the brake system cross matches... you will need to make sure that the 18" wheels that you have can actually be installed over the bigger brakes...

[racingbmwm3]

Style 58, 69, and 99 are confirmed to fit according to this thread:
http://www.xoutpost.com/bmw-sav-foru...els-4-8is.html
I have an aftermarket 18" that clears, so it's possible that almost any 18 will work. Definitely nothing smaller though.

And yes, as long as the master cylinder and the DSC pump are the same part between the 3.0 and 4.6/4.8 you should be fine just installing the caliper brackets/calipers/discs.

[bcredliner]

Originally Posted by TerminatorX5

the rear rotors on the iS are vented... the rotors are bigger to begin with, so the 18" wheels are the bare minimum that you will be able to pull over those rotors...

Mechanically, you should be able to put the bigger rotors and the calipers, i am not sure about the hydraulics though... you should run the real OEM to cross reference the brake systems between the regular 3.0 and the 4.6 and see if the brake system cross matches... you will need to make sure that the 18" wheels that you have can actually be installed over the bigger brakes...

The rear rotors on the 4.6, at least in 2002, were not vented. The 4.6 came with 20" wheels and the front wheels are very close to the calipers, be sure wheels have the clearance you will need.

You may want to consider just upgrading the pads. Several aftermarket sources claim a 20% improvement.

[TerminatorX5]

Originally Posted by bcredliner

The rear rotors on the 4.6, at least in 2002, were not vented. The 4.6 came with 20" wheels and the front wheels are very close to the calipers, be sure wheels have the clearance you will need.

You may want to consider just upgrading the pads. Several aftermarket sources claim a 20% improvement.

even though i personally have changed all 4 rotors on my 2002 4.6iS, I may have forgotten if the rears were vented or not... however, a quick check of the RealOEM reveals that they were indeed vented, (VIN - LN78208), which as a matter of fact, was one of the selling points of the iS back in the day...

I am not saying that entire worldwide distribution of the iS had these brakes, as i had seen 4.6iS with 19" factory rims, and possibly without vented rears rotors... the US specs - rears were vented...

[bcredliner]

Originally Posted by TerminatorX5

even though i personally have changed all 4 rotors on my 2002 4.6iS, I may have forgotten if the rears were vented or not... however, a quick check of the RealOEM reveals that they were indeed vented, (VIN - LN78208), which as a matter of fact, was one of the selling points of the iS back in the day...

I am not saying that entire worldwide distribution of the iS had these brakes, as i had seen 4.6iS with 19" factory rims, and possibly without vented rears rotors... the US specs - rears were vented...

Yes, you are correct. Both front and rear are ventilated. I was thinking slotted.

[TerminatorX5]

here is a last 7 of the 4.6iS VIN - LN78208... you can use that VIN to cross reference to your own car...

[RFaber]

Thanx, the local dealership 'thinks' it may be possible, I was going to bring one of my 69 5 spoke wheels with me to try it all out. I'll post my findings!!

[Gregory891]

RFaber, I wrote a post about what you need for this. Terminator is spot on, you must have at least 18" wheels for the bigger front rotors and calipers. Find my post and you'll see the rest.