Review: Alpha Omega Racing Evo 350mm Brembo Rear Brake Adapter Kit - WTAC Edition

[timmy_89]

Review: Alpha Omega Racing Evo 350mm Brembo Rear Brake Adapter Kit - WTAC Edition

Hey all, decided to put a review together for the Alpha Omega Racing Evo 350mm Brembo rear brake kit (WTAC edition). This is a new version of the rear adaptor kit developed by Alpha Omega Racing, designed with the intention to meet World Time Attack Challenge clubsprint rules. I have been running the original rear kit for the last 6 months (?? maybe longer lol) so this review will be more so related to the comparison when installing.

Company/Product:
Alpha Omega Racing / Evo 350mm Brembo Rear Brake Adaptor Kit - WTAC Edition

Price:
$400 plus postage

Link:
http://alphaomegaracing.com/p/149/c/72/Z32/ALPHA-OMEGA/Evo-350mm-Brembo-Rear-Brake-Adapter-Kit-WTAC-Edition.html

Purpose:
This kit allows you to fit rear Brembo calipers from an Evo 5-9 (all the same) with Nissan 370Z rear rotors (350mm diameter) to your R32/R33/R34/S13 (5 stud)/S14/S15/Z32/Z33.

What's included:
- Left and right adapters made out of one piece of 7075-T6 billet aerospace alloy
- Various high tensile bolts and high tensile washers
- Full installation instructions with pictures

What else you'll need:
- Mitsubishi Evo 5/6/7/8/9 Brembo rear calipers and brake pads
- Nissan 370Z rear rotors (350mmx20mm)
- Custom brake lines

Alpha Omega Racing is able to provide all of the above parts as well as parts and services (labour) for rebuilding calipers and even fitting if you are not comfortable doing so yourself. I personally opted to get the parts from Alpha Omega Racing for the rear kit for the convenience factor at the time.

The kit makes use of the Nissan 370Z rear 350mm rotors for better brake bias and heat dispersion. When using the front and rear kits designed by Alpha Omega Racing the brake bias is calculated to be a ratio of 69:31.

I have chosen to continue running Intima Performance Brake Pads and am using their Type SR pads in this application.

Test vehicle:
1998 Nissan Skyline R34 GTT - originally factory rotors and calipers, then upgraded to the original rear kit designed by Alpha Omega Racing

Unboxing the kit:
The new WTAC edition kit arrived quickly and was well packaged. Much like their other adaptors, these new adaptors are very light as you'd expect being made from billet alloy and appear to be of good quality. Alpha Omega Racing is etched on one side, whilst 'Made in Australia' is etched on the other. All bolts and washers were included along with installation instructions. I already had all other parts required as I previously had the original rear kit installed and was changing purely to meet WTAC clubsprint rules.

Installation:
Installation was pretty straight forward. The most painful part was actually removing the old kit due to the use of the hub spacer. Once this was removed and the factory parts were all bolted back up, the adaptor kit bolted straight on without issue. Normally I would have been required to trim the dust shield/back plate, but I had already done this when installing the original kit.

The calipers are required to be 'shaved' a little for fitment with this kit, my trusty angle grinder helped out here and made for easy work. The place that requires shaving has no effect on the performance of the caliper and is very minimal (see photo below). Once the calipers were sorted, I was able to put the rear rotors back on and bolt the calipers straight up! Fitment looks just as good as it did before with the original rear kit.

Performance:
In terms of performance, I have not had the car back on track after installing the WTAC edition rear kit. However having had the original rear kit on the car for some time now I feel performance will be similar. Will report back soon with an update though.

The original rear kit created a much better braking bias for the car. ABS is disconnected in my car so took a little bit to get used to how hard I could jump on the brakes, but once I adjusted I was definitely impressed with the increase in braking ability. Will provide an update on this once I've had the car back on track (after WTAC).

Overall Opinion:
Overall I would say I'm very happy with the kit. The quality of the new kit matched that of the front kit and I found the install to be fairly easy. The flexibility to either source parts yourself of purchase from Alpha Omega Racing is great, if you have the time to source your own parts you might save a few dollars, but if you want to buy everything together it makes the process quicker, and you essentially have a ready to go kit.

As mentioned, I will add some updates after WTAC, but if anyone has any questions regarding the kit, its install, or any other particulars, please feel free to ask me either in this thread or by sending me a PM. You can also read more into my car by checking out my build thread here:
http://www.sau.com.au/forums/topic/421419-timmys-r34-gtt/

[Roy]

What do you mean by WTAC compliant? I thought you had to use std mounting points...isnt that anything that bolts to the std hub?

 

Curious to see how these go, from memory you still have the ABS so intersting to see how the ABS reacts

[timmy_89]

On 10/2/2016 at 0:32 PM, Roy said:

What do you mean by WTAC compliant? I thought you had to use std mounting points...isnt that anything that bolts to the std hub?

 

Curious to see how these go, from memory you still have the ABS so intersting to see how the ABS reacts

 

The reason the previous rear kit wasn't compliant was because of the rule  “Original hub location must be retained”

With the install of the spacer it technically breaks this rule, hence the new kit.

[V28VX37]

Looks good except for the part on having to grind the calipers, especially so close to the mount.

Did the original non-WTAC kit require that or was it a completely different design?

[timmy_89]

12 hours ago, V28VX37 said:

Looks good except for the part on having to grind the calipers, especially so close to the mount.

Did the original non-WTAC kit require that or was it a completely different design?

The original kit did not require this, it used a slightly different offset adaptor and a hub spacer to avoid this.

I too was a bit weary on grinding the caliper originally but found it to be very minimal when I actually did it. There is zero impact on performance from doing so.

[Roy]

On 05/10/2016 at 10:32 AM, timmy_89 said:

 

The reason the previous rear kit wasn't compliant was because of the rule  “Original hub location must be retained”

With the install of the spacer it technically breaks this rule, hence the new kit.

I still dont get it. Dont you still have a spacer. Anyway. 

[timmy_89]

8 minutes ago, Roy said:

I still dont get it. Dont you still have a spacer. Anyway. 

There is a dogbone adaptor for the caliper to fit, but there is no spacer on the hub.

[omnigear]

so its 200$ per dogbone

 

[Roy]

When you think some setup time and materials and a labour rate to machine, droll and tap. A couple of hours work and materials seems reasonable. 

[sneakey pete]

On 06/10/2016 at 6:41 AM, timmy_89 said:

There is zero impact on performance from doing so.

until the caliper mount snaps off

[timmy_89]

14 hours ago, sneakey pete said:

until the caliper mount snaps off

I would say I had to shave off maybe 5% off the 'leg', if something is putting enough force on the caliper to snap the leg something else it going on lol.

[sneakey pete]

you've also created a stress concentration (looking at the one at the back of your picture), plus mounted them further out than stock thus increasing the torque acting on it.

Could be right but given the caliper is designed to minimize weight, therefor optimize for stress with a nice curve that reduces stress concentrations, i'd personally be very, very hesitant to do this mod.

[timmy_89]

16 hours ago, sneakey pete said:

you've also created a stress concentration (looking at the one at the back of your picture)

No sure if you're referring to the mark that I left on it with permanent marker?

[timmy_89]

16 hours ago, sneakey pete said:

i'd personally be very, very hesitant to do this mod.

I guess it's a personal choice, like all mods on a car. If someone is concerned about doing this then there is always the other kit that uses the hub spacer as an option

[Dose Pipe Sutututu]

Hey Tim, any more info on how the Intima brake pads stack up?