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9-04-2003
2004 RX-8
6 Speed w/sport
DSC & Traction Control Off
35PSI tires (Cold)
85 degrees F
32% Humidity
4525 miles
Third gear pull
100 Ft. Elevation
Fourth and fifth gear runs were about one percent less (normal variances between runs).
I have over a hundred runs on this dyno with my other car and it seems about right with other Dynojets with comparable cars.
Vince
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Last edited by compaddict; 09-04-2003 at 02:43 PM.
what is the spec sheet hp of your other car and what has it dyno'ed at on average in the 100 tests?
just looking at this graph i would say everything looks correct, except of course the peak HP. the 3 ports open at the correct rpm's and max power is at @8500 which is where it is supposed to be. it's just too low. i haven't commented in the dyno threads yet but i think now i am starting to agree with the fuel mapping people. otherwise i would have to say something is seriously wrong. i just don't get why this fuel mapping switch bit wouldn't be in the owners manual. was it in the "tech highlights" cd? i haven't burned and watched it yet.
Originally posted by zoom44 what is the spec sheet hp of your other car and what has it dyno'ed at on average in the 100 tests?
The other car is a CSP Miata and its output is coincides with other CSP Miatas with the same state of tune.
This Dynojet is as far as I can see the same as another Dynojet I ran the CSP Miata on one month before I switched dyno shops.
Wow, this doesn't look good. So far all of the dyno runs that I've seen are ~180HP at the wheels. That's 25 HP less than Mazda stated. I asked my dealer if he could find anything out, I doubt he will.
So what do you guys think? At which point can we expect the fuel maps to change and "release" the full power of the engine? Is anyone going to bring this up with their dealer/sales rep/regional rep?
Well, I paid for 205rwhp or 247 at the crank, and that's what I want! I haven't opened it up yet, but I may be disappointed when I do. Mazda needs to start talking right now before I start getting irate. Don't get me wrong, I love the car, I just want everything that I paid for.
Originally posted by Quick_lude So what do you guys think? At which point can we expect the fuel maps to change and "release" the full power of the engine? Is anyone going to bring this up with their dealer/sales rep/regional rep?
Vince, have you done any 1/4 mile runs yet?
I think the whole changing fuel maps thing is total speculation and at this point in time no one but Mazda knows why the HP is down so much.
I don't do 1/4 mile stuff but I autocross and my RX-8 seems fast enough!
Well if that run that was done with the G-tech is any indication, lower gear power is not a problem since he did pull of a mid 6 sec 0-60.. but the power up high seems to be lacking thus the mid 15's 1/4 mile time. I think everyone expects this car to dyno somewhere in the 200-210 whp area. Assuming for a min that the dyno numbers are off for whatever reason, DSC, etc, but if the car only does mid 15 in the 1/4 then that supports the 180whp numbers. The mystery continues...
I think it's unrealistic to think a switchover in the ECU mapping will suddenly find that 20 - 25 horsepower. And even if it does, having to wait until 20K miles would be seriously frustrating.
Actually, the secondary opens around 4000rpm, that one is the auxilliary/ tertiary port.
Is there a way to see a Torque curve from this data?
You are right of course!
To look at the data download the runviewer software and then open the files and select "Torque" by right clicking on where it says "SAE Horsepower" and if you want "RPM" instead of "Speed" do the same right mouse click trick on it.
So what do the two dips at 6.4K and 7.4K represent? They're rather large and the torque is definitely decreasing after the 6.4K dip. Did you "feel" those dips in power while on the dyno?
Maybe it would be a good idea to run some '8's around the country until they had a quick '15 thou' on them so a realistic dyno could be done.......Oh, yes, Mazda felt the need to do this already, but they aren't talking................
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doc
__________________
Hobbies: Filling in questionnaires complaining about Jarman Mazda.
So what do the two dips at 6.4K and 7.4K represent? They're rather large and the torque is definitely decreasing after the 6.4K dip. Did you "feel" those dips in power while on the dyno?
Those are the ports and variable intake paths opening. There's a slight dip @ 4000 which is the secondary port opening, then the tertiary @6300 and fresh air duct and variable intake path @ 7500
Those dips are also visible on the other dyno chart in another thread
that torque number seems to be way down, preportionally to where the power is down, that's where we should be focusing, now i'm kinda scared about my order, have we got any dyno charts from teh jdm models
The torque numbers (and hence the Horsepower) are pretty good up to 6000 RPM. about 18% lower at the wheels than Mazda's claims for power at the flywheel (15%-18% drive line losses are considered standard). It is after that where power numbers are considerably lower. Attached once again below is the Mazda torque curve from the press-kit (1 nM = .74 ft-lb). It is the power at 8500 which is supposed to be 153 ft-lb and is only about 111 ft-lb. That is 37.5% reduction in torque (and thus 37.5% reduction in power.) So at the highest RPMs the car is down about 20% more than what could be attributed to drive line losses.
So on a 0-60 run where you are probably going to be between 6000 RPM and 9000 RPM to create the fastest run. The car is going to have about 10% less power than it should. Which means you are going to be about 10% slower than you normally would be. That is why Car and Driver did 0-60 in 5.9s and the best claim so far from new owners is 6.6s (I believe)
Bottom-line: Mazda, at some point we need our 20% of high RPM power back.
-Mr. Wigggles
Ps. just a reminder that horsepower is derived directly from the torque curve: HP = Torque X RPM / 5255. The two are completely inter-related and that is why the ft-lb of torque at 5255 always equals the horsepower.
Last edited by MrWigggles; 07-31-2003 at 12:18 AM.
Put some quick miles on........
Linear Mode
