NC 20BPP Time Attack / Track Car - Build Thread

Postby **orx626** » Mon Mar 16, 2009 10:24 pm

After a discussion with a friend of mine today I did a bit of massaging of the caliper bracket profile to improve airflow around the caliper. It will be machined out of 6061 T6 aluminium alloy and has a mass of 506 grams. The next step is to see whether the right hand bracket is just a mirror image of the left hand bracket. Mazda do do some strange things from time to time, so I may have to do a little bit more R & D for the right hand bracket. Once done, off the to the CNC machine the solid model will go :!:

Here's the revised bracket.

Cheers,
Danny

Postby **orx626** » Thu Mar 19, 2009 10:55 pm

I thought is was about time that I put up some piccies of some actual parts rather than just pretty CAD ones.

The below photos are of the trial fitment of the 355 x 32mm rotors.

This is the "race" rotor beside a standard RX-8 rotor (323mm x 24mm).

.....and they actually fitted!!!!

.....I couldn't help myself, I had to throw "Big Red" up there as well!

Initial measurements are pointing towards the RH caliper bracket being just a mirror image of the LH.

Cheers,
Danny

Postby **mx52nv** » Thu Mar 19, 2009 10:58 pm

It is coming along nicely Danny... :mrgreen:

Are those the 8 piston Brembos......*thud* (body hitting ground after another fainting spell :lol:

)

Postby **orx626** » Thu Mar 19, 2009 11:09 pm

mx52nv wrote:It is coming along nicely Danny...
Are those the 8 pistons Brembos......*thud* (body hitting ground after another fainting spell )

Cheers Les

.....and to answer your question.... YUP!!! :mrgreen:

PUR157 · Postby **PUR157** » Fri Mar 20, 2009 12:20 am

I think I shall join mx52nv

*faints

Postby **Okibi** » Fri Mar 20, 2009 12:25 am

I would have thought you'd cad up some light weight top hats for the brake rotors, you could get them red anodised to match those sexy calipers :mrgreen:

Postby **orx626** » Fri Mar 20, 2009 8:45 am

Okibi wrote:I would have thought you'd cad up some light weight top hats for the brake rotors, you could get them red anodised to match those sexy calipers

...and yes 2 piece alloy hat and rotor will eventually reside there

.....but the fact that an 'off the shelf' rotor suits the application is of great significance.

Cheers,
Danny

Postby **mx52nv** » Fri Mar 20, 2009 2:17 pm

Agreed - very true, Danny.
Now you just have to start doing it for NAs & NBs too :mrgreen:

Adsy01 · Postby **Adsy01** » Fri Mar 20, 2009 7:44 pm

With brakes that big some people might think you plan on driving it fast... :lol:

I really LOVE this project, it really will be the "complete package" keep it up the great work!

Postby **orx626** » Sat Mar 28, 2009 9:33 pm

Adsy01 wrote:With brakes that big some people might think you plan on driving it fast...

I really LOVE this project, it really will be the "complete package" keep it up the great work!

Cheers Adam. For the car to be a "Complete Package" has certainly been my goal. I'm hoping that the brakes will match the engine performance. :wink:

Regards,
Danny

Postby **orx626** » Sat Mar 28, 2009 11:48 pm

About a month ago I reviewed the project with regards to the supercharging of the 13B MSP engine. The program was to initially fit up the low boost non-intercooled Blitz kit whilst I developed the intercooled Eaton M90 option. Well as I've commented on it many times in thread, work and home renovations are still continuing to take precedence over the track car build...which is fair enough! However, it is over three years since I embarked on the project and I'm still not far passed half-way....as far as required hours is concerned....and I don't want this build to go much past the end of this year.

About three years ago I met a guy with the same passion to develop a positive displacement supercharger kit for the RX-8 and at that point in time he was in the early stages of testing. Those of you who with an interest in Mazda Rotaries (especially RX-8's) may have heard of him by his username on some other Mazda forums which is Hymee. Mark (Hymee) was the first to locally offer an aftermarket cat back exhaust for the RX-8 (amongst other products over the past 6 years). But in recent times he became one of the first in the world to crack the factory RX-8 ECU and has developed software to re-map and re-flash the ECU as required. This software was really the linch pin in the supercharger kit project. How great would it be to have a supercharger kit on the market where you don't need an aftermarket ECU or even a piggyback ECU to get the boosted engine to run at its optimum!!! :twisted:

I have monitored Mark's progress very closely over the past three years and was stoked late last year when he told me that his first production run of kits was about to begin. The best part is that he is a local!

Obviously one of the most important parts of a supercharger kit is the supercharger. One thing that I really liked about Mark's kit was his choice of supercharger. Mark had bitten the bullet and based his kit around what I believe to be 'the best' positive displacement supercharger available on the market; the Opcon Autorotor. The Opcon Autorotor is a screw compressor as opposed to a Rootes Blower with a twist which I was going to use (Eaton M90). The main difference is that it has an internal compression ratio unlike the Rootes which just pushes air...boost is generated solely by the difference between what your engine can digest and what the blower can pump. A screw type compressor actually dispenses compressed air. Further to this benefit, is that it is far more efficent in both volumetric and thermal efficiencies when compared to the Rootes type.

Here are some images of Hymee's (Mark's) RX-8 supercharger kit....the engineering is very, very impressive. He has done thousands of kilometres of road and track testing with the kit on his own RX-8.

Installed.....

Key kit components.....

Pretty impressive hey!!!!

In late January Mark returned to the engine dyno for final tuning so that performance numbers could be documented. Here's a quick vid of the engine dyno setup....

Well the numbers were simply astounding. Bare in mind that the engine had a chequered past as it was one of Mazda's test units for knock sensor tuning, been in a Mazda 323 wagon drag car for a while (naturally aspirated), all prior to having the supercharger bolted on for ECU tuning. The engine's exact condition was really an unknown...all they knew was that it was still running after the floggings it had been dealt :lol:

. The engine is completely standard (ie. never been opened, therefore all standard seals and porting), although it did have aftermarket extractors. In naturally aspirated form this engine generated 225 flywheel horsepower...but with 13 psi up its proverbial on Premium Unleaded it made 340 flywheel horsepower :shock:

...and with more aggressive timing on E85 at the same boost, generated 360 flywheel horsepower :shock:

. Refer to the below graphs. Another point of mention is that the tuning was done by a very well known tuner in the Australian Rotary scene, Phil Laird...affectionally known as Grandad

. His involvement in the project further supports Mark's commitment to producing but nothing but the best quality product.

I'd say by now most of you who have just read the above have guessed what I've done

. Yup, you're right...I've ordered a kit for the NC!!!

Of the 11 kits Mark is building, 8 are pre-sold (local and internationally), with some customers even paying in full! We have decided to go with a 2.6 litre per rev compressor for the NC :twisted:

and chase a reliable 400 fly wheel horsepower. Now that I've put it in writing I've got to deliver the goods! :lol:

The kit is expected to be ready to bolt on in late June....I can't wait!!!!

Cheers,
Danny

AJ · Postby AJ » Sun Mar 29, 2009 10:06 am

I just HAD to click on that youtube link...............heard a twin screw on a V8 before, but never a rotor.........sounds pretty sexual don't it?? :oops:

that is some setup too, looks nice & stock with all the engine covers on it, I think the distinctive twin screw compressor whine might give it away but :lol: