E92 M3 AP Racing BBK Review (long)

[AP Racing - Chris_B]

Originally Posted by STALKER

Chris,
Any chance if AP in the UK can send us a pic of the BBK with a OEM 18" 260 wheel?
The other pic is def a 19" wheel.

While I don't yet have an image of the 368x36mm kit behind a Style 260, here is the response I received from the man who leads these projects:

I have no info on the US wheel; all I can state is the European 18” & 19” look identical on the E92 M3.
It’s definitely the 18” because I took the photos and the actual profile from this wheel was used to detail the kit.
Zoom in on the tyre its marked 18”.
This was also the case on the E46 M3 / CSL models where both sizes looked identical.

I don't know the differences between the 18" wheel in the picture and the Style 260, but AP is getting no fitment complaints from owners with those wheels. I'll keep asking for pics anyway. We do know for sure that the 18" Euro wheels and the 18" N.A. market (run flat) wheels are different and made by different manufacturers.

Chris

[signes]

Not sure I follow that. I guess it is irrelevant what he is saying if that original pic was an 18. Only thing I can think of is that it is an 18" replica of the Style 220/OEM 19. Plenty of places sell those.

[signes]

BTW, also corrected my earlier post - meant 219M for the style number for US 18s, not 216.

[southlight]

Originally Posted by AP Racing - Chris_B

While I don't yet have an image of the 368x36mm kit behind a Style 260, here is the response I received from the man who leads these projects:

I have no info on the US wheel; all I can state is the European 18” & 19” look identical on the E92 M3.
It’s definitely the 18” because I took the photos and the actual profile from this wheel was used to detail the kit.
Zoom in on the tyre its marked 18”.
This was also the case on the E46 M3 / CSL models where both sizes looked identical.

I don't know the differences between the 18" wheel in the picture and the Style 260, but AP is getting no fitment complaints from owners with those wheels. I'll keep asking for pics anyway. We do know for sure that the 18" Euro wheels and the 18" N.A. market (run flat) wheels are different and made by different manufacturers.

Chris

This information you got is definitely wrong. Unlike the E46 M3 models, the wheel designs look different. I run the standard 18's Style 260 on my Euro spec car and they look exactly like this picture signes posted:




The picture you got shows the 19's Style 220 (or some replicas, but I doubt that due to the low profile of the tires).


Best regards,
south

[GewoW]

Guys, does anyone know if the 378mm version is sold in NA (CP5555T1046BK.G8) and if this fits under stock NA-spec 18s WITH spacers?

[AP Racing - Chris_B]

Originally Posted by GewoW

Guys, does anyone know if the 378mm version is sold in NA (CP5555T1046BK.G8) and if this fits under stock NA-spec 18s WITH spacers?

Yes, it is sold in NA. No, it will not fit under the run-flat US-spec 18's even with spacers. It is not a spoke issue, but a barrel clearance issue. The run-flat wheels have a lower "drop center". Even if the caliper is shaved slightly (not recommended!), there is still no room left for wheel weights.

The gain from 368mm to 378mm (only 5mm on the radius) is too insignificant to warrant even attempting it without 19's.

Chris

[aus]

Is there a significant advantage of the 378 compared to the 368mm kit? Is the rotor the same thickness and are the calipers the same?

[AP Racing - Chris_B]

Originally Posted by aus

Is there a significant advantage of the 378 compared to the 368mm kit? Is the rotor the same thickness and are the calipers the same?

Same calipers and rotor thickness. Also, both are strap drive. There is very little difference between the two, only that the 368mm kit was developed to fit into 18" wheels.

[aus]

Thanks.
I've just never seen any vender offer the larger size.

[GewoW]

Originally Posted by AP Racing - Chris_B

Same calipers and rotor thickness. Also, both are strap drive. There is very little difference between the two, only that the 368mm kit was developed to fit into 18" wheels.

Is there a bigger sweeping area for the pads on the 378 kit? Also, there is more surface area overall so I would expect it to cool better than the 368?

[AP Racing - Chris_B]

Originally Posted by GewoW

Is there a bigger sweeping area for the pads on the 378 kit? Also, there is more surface area overall so I would expect it to cool better than the 368?

The same exact pad is used for both, so there is no difference in swept area. Either way, it is more than adequate. The rotor is slightly heavier, so in theory there is more thermal capacity. They are both use a 72 curved-vane core design, so in reality cooling is very good for both.

The reason the 378mm exists is that AP Racing in the UK did this design first for a European tuner who was only using 19" wheels. When the track day guys started clamoring for a kit to fit their preferred wheels, a slightly smaller rotor casting was available to do the job. 368mm kits vastly outsell the 378mm variant worldwide, but both remain available. If it were my car, I would be running the 368mm without a doubt.

Chris

[AP Racing - Chris_B]

Originally Posted by aus

Thanks.
I've just never seen any vender offer the larger size.

Other than it is really redundant, the main reason is that the 378mm kit is imported from the UK. It often takes anywhere from 8 to 12 weeks to land in the U.S. Not too many people have that kind of patience after they have made the decision to upgrade. However, the larger kit can be purchased through the forum vendors as long as one is willing to be patient.

[GewoW]

Originally Posted by AP Racing - Chris_B

Other than it is really redundant, the main reason is that the 378mm kit is imported from the UK. It often takes anywhere from 8 to 12 weeks to land in the U.S. Not too many people have that kind of patience after they have made the decision to upgrade. However, the larger kit can be purchased through the forum vendors as long as one is willing to be patient.

Is there a large price gap between the 2 MSRPs?

And thanks so much for the info btw!

[AP Racing - Chris_B]

Originally Posted by GewoW

Is there a large price gap between the 2 MSRPs?

And thanks so much for the info btw!

About $100 difference in MSRP.

[aus]

Chris, thanks for all the good info.
Next question is if the 378mm kit fits behind VOLK TE37 style wheels. I doubt anyone in the US would know. The Brembo 380mm kit does fit behind these wheels.

[GewoW]

I hope Chris knows that when I get a BBK it will almost definitely be an AP kit mostly because of his amazing presence in this thread and great support. It's good knowing that someone is here to help out (spec/info-wise).

[AP Racing - Chris_B]

Originally Posted by aus

Chris, thanks for all the good info.
Next question is if the 378mm kit fits behind VOLK TE37 style wheels. I doubt anyone in the US would know. The Brembo 380mm kit does fit behind these wheels.

Eddie at Mackin will know or can find out. I'll get some templates over to him and ask to have them checked. Are you looking at 18's or 19's? In which width & offset?

[aus]

The big news is if they'll fit under 18" wheels for our car. The VOLK track wheels for our cars usually run 18 x 9.5 et15 and 18.10.5 et23- of something close to that.

Thanks again.

[GewoW]

Originally Posted by aus

The big news is if they'll fit under 18" wheels for our car. The VOLK track wheels for our cars usually run 18 x 9.5 et15 and 18.10.5 et23- of something close to that.

Thanks again.

Originally Posted by AP Racing - Chris_B

Yes, it is sold in NA. No, it will not fit under the run-flat US-spec 18's even with spacers. It is not a spoke issue, but a barrel clearance issue. The run-flat wheels have a lower "drop center". Even if the caliper is shaved slightly (not recommended!), there is still no room left for wheel weights.

The gain from 368mm to 378mm (only 5mm on the radius) is too insignificant to warrant even attempting it without 19's.

Chris

^^^

[AP Racing - Chris_B]

Originally Posted by aus

The big news is if they'll fit under 18" wheels for our car. The VOLK track wheels for our cars usually run 18 x 9.5 et15 and 18.10.5 et23- of something close to that.

Thanks again.

I've got a yes from Mackin/Volk on any of the AP Racing front kits clearing the 18x9.5 TE37 in an ET+22 on the E9x M3. I'm still awaiting a gap dimension so we can understand wheel weight clearances as it can't be much with the 378mm kit.

Chris

[dawgdog]

I have Volk TE 37s 18x9.5" et28 and the 368mm kit clears with room to spare. I would be quite surprised if the 378mm kit didn't clear as well

[AP Racing - Chris_B]

Volk importer says: "It's really really tight – I would say not much – just enough to clear the brakes – not weights – usually people put the weights in non contacting areas to try to offset."

Choose whichever you prefer. We do recommend the 368x36mm system for a variety of reasons, mostly related to availability, service and support. These easily outweigh the negligible (less than 5mm or about .180") increase in effective radius.

Chris