Dragonfc3s

All of the aftermarket mufflers, intakes etc list the hp gains for 6 port engines only and I've only been able to find dyno's of stuff on that engine. They at the best only offer a few hp on the 6 port from from what I've seen so far. I'm wondering if anyone here has dynoed the 4 port with the these kinds of mods as I'd like to know if the gains are the same or simular to the 6 port or if maybe it will wake the 4 port up with even larger gains in power. If anyone here has any info I would love to hear it..

Thanks,
Chris (aka Dragon)

JeRKy 8 Owner

The RX-8 has been out for over 2 years now, and I still have yet to hear from anyone who had dynoed their automatic.

Also, the 4 port makes the same disappointing gains as the 6 port with exhausts, intakes, mid pipes, etc.

whenson417

I dyno'd my automatic in the spring and got a whopping 135hp to the wheels. I think I would have done a little better if I had reset my ecu but not much. I had about 12000 miles on it then and I am now pushing close to 28000. Since the dyno I have added the REVI and ram duct. I think the car has a little more power but not a lot. When I have the extra cash I will get her done again just to see what she can do now.

YanMan08

Hears a story for ya. One of my friends work at mazda in wayne, nj. This one guy brought his rx-8 for intake, pullies, exhaust, and computer upgrades. when they put it on the dyno no horsepower gains what so ever. They even call professional mazdatechs to see if they can increase the horsepower but failed. They said the only way that you were going to get horsepower gains is turbo or supercharger.

NiNjA99

computer upgrades eh? since when were people able to upgrade the ecu? maybe you mean ecu flash?

JeRKy 8 Owner

135 whp? Wow.

Dragonfc3s

I just found an artical where Blitz dynoed a stock AT and got 163.8ps. With their supercharge kit it made 203.6ps for a gain of 39.8ps. It's all in Japanese, so I'm not sure if that was to the wheels or corrected to the flywheel... For referance they also did a 6port and got 177.5 stock and 226.5 with the supercharger for a 50ps gain... They did both tests @ 0.4kgcm boost (5.88psi SAE). They list the price of their supercharger kit as ¥498,000 or $4,527 @ the current Yen to $ excange rate. That comes out to a $113.74 per ps gain for the AT.

therm8

check out Hymee's supercharger thread. He's putting up fantastic low end numbers for the 6 port (+40-50hp down low), so his 4port sc'r should put up at least equal, but probably better low end numbers. He's still tuning the high end. If he or Pettit can give me ~40-50hp across the rpm range, I'll be all over it.

As for 135hp, the car just doesn't feel like a 135whp car, and it's not exactly geared for max performance. I'm not doubting the dyno, but I also don't doubt that my car is putting up better numbers than that. When I get a supercharger I guess I'll do some before and after dyno's.

JeRKy 8 Owner

It kind of makes sense. The 6 port dynos range from 170s to 180s ...so 4 ports being in the 130s to 140s sounds right.

therm8

But quite a few 6ports have dyno'd high 180's low 190's. And 4ports overseas dyno in the 160's where they're supposed to, so perhaps the US tune just sucks. The ecus for Hymee's and Pettit's superchargers will fix that.

Dragonfc3s

Well I have a J-Spec 4 port, so once I get the engine broken in I'll put her on a dyno to see what she pulls. Might be a few weeks before I can get anouther 1,000 kms on the engine since I'm on a 5-10 mile wide x 67 mile long island... Thanks for all the responses so far...

09Factor

^^^

I didn't think that the short block itself was ported any diffrent between the States and AU/JP. I believe the diffrence is in the tune of the ECU mapping.
Are you saying you have a JDM ECU?

Mickeyblue

theres little differnces in the 4 porters around the world, most obvious is some get 2 oil coolers and some dont!...why i dont know!

Dragonfc3s

lol.. I'm saying I live in Japan, RHD, climate control, little lights below the mirrors and clear winkers stock from Mazda here in Okinawa Japan...

Dragonfc3s

Unfortunatly mine only has one and Okinawa gets pretty damn hot. Mazdaspeed Japan sell the additional oil cooler here with the extra oil lines for ¥52,000 and they told me they would put it on the car for an additional ¥10,000 (about $550 total @ the current Yen rate). That will be one of my next mods after hearing about all the AT's having problems in Arizona and Texas...

Mickeyblue

see thats what i find so hard to work out i mean the UK is generally cold and wet (ok we buy more cabros than anywhere else in Europe but still is not the sunniest place) so why do we get 2 oil coolers as standard?

where as hotter plaes around the world only get one?

Dragonfc3s

Hrm.. I was stationed in Germany for 3 years, so maybe they decided to give the surrounding European countries the double oil coolers as a precaution to them possibly hitting the autobahn and the higher speed limits in that area of the world?? Here in Japan the Highest speed limit you'll find is 80kph in Okinawa and I think there are a few places in mainland that go to 100kph, regardless it's usually too congested to hit any high speeds for any great amount of time so they went cheap and only gave us one...

Mickeyblue

100 KPH Jeeeeez thats shocking!!!!

is that enforced? i know in the UK most coppers wont pull you over til your over 85 mph or about 137KPH even then to get much more than a little 'do you know how fast you were going' speach is unlikely!

Dragonfc3s

Yep, it's enforced... as a mater of fact if you are caught going more than 30 kph over the speed limit it Japan it goes from a mister meaner to a criminal offense. You will then have to go to court and more than likely loose your license for a time and pay a huge fine... There are quite a few speed camera's in Japan now as well, nothing like the UK yet, but they are working on it...