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I put my 8 on the Dyno Today with unexpected results:
Best pull was 184HP and was expecting 205 or so. Has anyone done Dyno's?
DSC was off
93deg F (results temp corrected)
ABS freaked but had no apparent effect
DSC light still came on solid but only after accidentally tapping the brakes.
I will scan the dyno results tonight.
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I put my 8 on the Dyno Today with unexpected results:
Best pull was 184HP and was expecting 205 or so. Has anyone done Dyno's?
DSC was off
93deg F (results temp corrected)
ABS freaked but had no apparent effect
DSC light still came on solid but only after accidentally tapping the brakes.
So, two dyno's now and both fall well below what the high-power should be, and that's taking into the effect the expected loss of power to the back wheels. I hope we start getting a definitive answer on what is going on...
Max torque seems right on the money. Asuming its about 130 ft/lbs with 17% drive train loss (from the graph) you get about 157-158 ft/lbs of torque at the flywheel. Sound right to anyone else?
I think it's genuine. You can see some marks around the top left, and bottom left sides of the image that are by no means even, which you would normally see in a computer generated image.
1 - not all dyno's give the same numbers, dunno the reason why, but different dyno's give off slightly different numbers
2 - on a dyno you cannot develop your full potential power that you can while one the road, because your intake has to work harder to get air (since it's not being shoved through it like it when your car is moving), but also you are drawing in substancally less cool air (and thus less dense), usually warm to hot air depending on the layout of the air surrounding the dyno, if you want a more real world results get some large fans to help the inatke get cooler air
As has been suggested, someone who can needs to contact Mazda directly to clear this up. We need to know if the car is designed to produce low power for a while until run in or whether this is some other issue. If it's going to STAY like this then something is seriously amiss right?!
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Titanium Hi-Power.
Leather / Nav
Ordered Mar 03
Originally posted by 1stRX8
DSC light still came on solid but only after accidentally tapping the brakes.
I thought that if the DSC was completely off it wouldn't come back on unless you turned the ignition off and restarted the car. Maybe it wasn't completely disabled.
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I'm back home at La Isla Del Encanto Puerto Rico!!
I thought that if the DSC was completely off it wouldn't come back on unless you turned the ignition off and restarted the car. Maybe it wasn't completely disabled.
This is so.
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Titanium Hi-Power.
Leather / Nav
Ordered Mar 03
The car has a thousand miles on it. I have been a rotary enthusiast for 20 years and have NEVER even heard anyone suggest that the engine would continue to build power after a thousand miles. I don't even remotely believe that.
I will certainly go back on the dyno a month from now to see the results. If it makes more power I will apologize.
While I do believe that not all dynos are created equal - I seriously doubt they would vary by 25+ HP. The shop that I went to does high-end work that is subject to scrutiny by other high-end shops. If the numbers don't come close to other dyno's they would not be working on $500,000 german race cars for long.
The RX-8 hardly depends on Ram-Air for horse power. We had the hood open with a few high-velocity fans pointed at the nose. A third gear pull takes at most 9 seconds or so. Not exactly enough to overheat the engine or have any real effect on the life of the engine. After five pulls in about 45 minutes - the run-to-run comparo was VERY similar. The ports open at exactly the same point every time. The HP is very consistent.
I could put a few thousand miles on it, take it out of the car, and put the engine on an engine dyno and expect to see just over 220HP. Even lowering the temp 30deg. wouldn't make 27 more HP and the Dyno computation takes pressure, temp, and humidity into account.
The pulls were made with DSC on and off - it made no noticable difference. Once the system detects a gross error it apparently shuts off and the light (car with squiggily lines) stays lit constantly. If the disable switch does not disable it fully then the dyno results are inconclusive. That would also mean ther is no easy way to check up on Mazda claims of power.
This was never meant to be a conclusive test. I would hope that a few others will take a dyno run and see what they get. I plan on contacting Mazda to simply ask why I might see this result on a dyno. I look forward to hearing some answers.
btw: what's your milage, how did you break her in, and what fuel are you running?? have you had your post-break-in tune up??
Mileage: 1010 miles
Fuel: 93 octane although I bet that would make only a slight difference.
Break-in: I drove it on a 600 mile road trip. Fairly easy driving. A couple of bursts here and there. Generally following the rules, however I do believe that the break-in specified in the manual is exceptionally cautious.
What in the world is a post-break-in tune up? changing the oil? Checking the tire pressure?
Originally posted by 1stRX8 If the disable switch does not disable it fully then the dyno results are inconclusive. That would also mean ther is no easy way to check up on Mazda claims of power.
Simply pressing the button disables the DSC (and traction control?) until and unless the ABS is engaged, apparently. Pressing and holding the DSC button for several seconds disables it completely until the ignition is turned off and back on again. When in this mode, the DSC OFF and Traction Control ("slippery when wet" lookalike) lights both remain on constantly.
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1973 RX-3
1975 RX-3
1979 RX-7
1985 RX-7 GSL-SE
2004 RX-8 Winning Blue Sport Ordered 1/8/03; Delivered 7/25/03 ; Returned 10/21/03
2005 RX-8 Velocity Red Sport delivered 12/05 returned at lease end 12/07
Originally posted by 1stRX8 The car has a thousand miles on it. I have been a rotary enthusiast for 20 years and have NEVER even heard anyone suggest that the engine would continue to build power after a thousand miles. I don't even remotely believe that.
actually engines do get more power as u put more miles on it, to a certain extent. one of those car magazine did an article on it, they had a is300 from when they first tested it and then they tested it again at like 20000 miles and the car gained like 20% more power and a few tenths quicker. several people at is300.net can also confirm power increases
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getting a new sig since sputnik is being such a **** about it
Next time hook up a voltmeter to the Throttle Position Sensor so you can see if the throttle is open 100%... with an electronically controlled throttle and DSP/TCS you never know whats going on unless you monitor the TPS
.....and the car gained like 20% more power and a few tenths quicker.
The dyno shop is at most 300ft from my office. I will take there and do a pull every few thousand miles. I certainly hope the power increases, but my hopes are low.
Take a look at the air fuel ratio. It gets progressively richer as the motor goes past 5,000 rpm. This keeps internal parts nice and cool, and keeps the stresses down on the bearings and gears.
The motor is pig rich by the time it reaches 8,000 rpm.
Who knows what the timing curve looks like.
Mazda is simply running the engine in safe mode while all the internal parts are getting to know each other.
This is a wise move for any performance car. Just imagine what the lot jockey, salesman, and test drivers will do to a performance car before it even clocks 20 miles!
; Returned 10/21/03 
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