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Hi guys, as the topic says, i want 100+kw at the rears of my DAILY dríven naturally asperated nb8a. Am i dreaming??

Before we get carried away, I think FI is great and it has its place. But given the way i drive and the fact i like doing things a bit different ive decided i want to go naturally asperated.

so far ive done full mania intake, x force extractors, hi-flow cat, 2.25in exhaust, smb rear muffler and 10mm leads.

My last dyno graph shows im running about 84kw at the rears, ive got an ecu on the way but im guessing that will only give me another 5 or 7 kw.

i take it cams are my next step??

any suggestions on what to get cam wise?? heard the 805c's are meant to be ok for a daily (not real clued up on these sorts of things, but i dont want all my go on the limiter, mid range would be nice if i could get it)

Will an adjustable cam gear on the exhaust side help?? (would do both sides except for damn cas being on the front of the rocker cover)

is the cam gear on the exhaust the same as the intake?? ive heard whispers they are different.

would 2.5in exhaust help (if so some one want to buy my 2.25 exhaust please ) or is it just going to make things really noisy and not much else (dont want my exhaust to be much louder than current or drone down the express way)???

will i need quads to get to my goal??

as my 5 is a daily i DONT want to do forgies or take the head off etc unless i have a dead engine (which i dont want either).

thanks in advance guys,

cheers ben.

moo.......

ECU, Cams and ITBs might get close, I think CT's done a lot of research in this area.

BTDT

How deep are your pockets? How much are you prepared to sacrifice in terms of civility in a road car, let alone a daily driver (and know that your threshold for bad tempered engine behaviour will lower with time ), suffice it to say that the GM which served as road car and for track days etc (1996 class win in NSW Supersprint C'ship) has been retired from track duty and the good bits are going into the new racecar !

Start with headwork, cams, adjustable cam gears, ecu, lots of dyno time ...

IRTBs are nice, and sound nicer, but probably not necessary for a street car - good for response, if you want HP you want a long intake, not shorter.

PM me if you want more detail, such as I can remember (it was a long time ago....)

are you looking for peak power? or total area under power curve?

i guess for for peak, do what the others have said. Dunno if ITB's are necessary for what you want to achieve, but it is a possibility. IIRC you would need to find someone who knows how to tune the thing as well, which might necessitate a stand alone ECU.

i guess cams, and having the cams tuned to the car to suit would help. Of course this might also require uprated fuel injectors to meet the higher fuel requirements.

but of course, i could be completely wrong =P

There is no reason why you cant put an adjustable cam gear in the intake too if you think gains can be made there

hmm, well Mxcrazy has 92 rwkw on the mania dyno with 2.5" exhaust and the mania intake.
I could see that reaching 100+ with cams and ECU.
I wonder how much of it comes down to the individual engine tolerances, lots of stock cars seem to get different values

the info is great guys , keep it coming.

WOO, i would do both cam gears, BUT as far as im aware the crank angle sensor on the front of the nb8a motor only works with the OEM cam gear im happy to be proven wrong tho

Just have to have the right gears and pins
They are Fidanza wheels that I modified to suit. I also have another set that are a direct replacement that I was going to fit but have found the Fiddies are just fine for what I run.

You could always get a set of the ebay gears http://cgi.ebay.com.au/MAZDA-MX5-MIATA-CAM-GEAR-GEARS-PULLEY-B6-BP-NB6-NEW_W0QQitemZ380076642097QQcmdZViewItem?hash=item380076642097&_trksid=p3286.c0.m14&_trkparms=66%3A2%7C65%3A1%7C39%3A1%7C240%3A1318
All you have to do to make them work is to replace the stainless steel pickup pins with mild steel pins (cut up 6 mm bolt works fine)

Toda also make a cam gear to suit the NB8A

I have the Toda Cam gears in my NB8A. No problems with the CAS in 4 years of running them.

Alex wrote:hmm, well Mxcrazy has 92 rwkw on the mania dyno with 2.5" exhaust and the mania intake.
I could see that reaching 100+ with cams and ECU.
I wonder how much of it comes down to the individual engine tolerances, lots of stock cars seem to get different values

that's a fairly optimistic dyno. i recall roddclarke got 96rwkw with full exhaust, intake and ecu, and jolt got 98rwkw with full exhaust, intake and ecu as well.

i am confident i will crack 100rwkw with my setup.

this will consist of
ported/shaved head
thinner headgasket
oversized valves
stiffer valve springs/retainers
camgears
895c cams
piggyback ecu
2.5 inch exhaust
4-1 extractors
short ram intake

2nd stage will consist of

ITB's
rebuild bottom end/stroker kit
standalone ECU (itb's need a standalone to run on the mx-5)
bigger fuel pump
bigger injectors

with that i would expect 120-130rwkw, which i believe would be sufficent for a lightweight like the mx-5.

however there is not much information/conformation on NA MX-5's, most just save the hassle and go F.I

like others said, how deep are your pockets? F.I is definately easier and cheaper, but there isnt the cool factor like a N/A MX-5, if you do tend to go extreme, you will loose driveablility too which you dont want on a daily driver.

MXHEVN wrote:with that i would expect 120-130rwkw

I think that is very optimistic. Even if you tuned on Mania's dyno.

Boags'MX5 wrote:I think that is very optimistic. Even if you tuned on Mania's dyno.