dmp

I don't buy the heat issue - Every dyno I've done, with almost every rx8 I've seen dyno'd used 5th.

KYLiquid

yeah thats a new shop and a new dyno.....they said they were having problems with posting the RPM data on the dyno charts.......needless to say if I want hanging out with my friends and it wasnt so cheap I wouldnt have gone, at least I know thats ANOTHER bad shop in orlando not to deal with.

I think their WBO2 is also off.....the car that ran after me was putting out so much unburnt fuel that we were all crying but it was reading 13-14 AFR.....whatever.

Ill have dynojet numbers from a good dyno, RPM based tommorow.....after work Im using our shops dyno....the only thing I wont have is WBO2 data on the chart cause the WB is broken, but Ill be able to watch it on my in car sensor.

KYLiquid

I agree, somewhat

your gonna get high EGT's when you go WOT, its a rotary, you cant really stop that, and driving the car up to 5th vs 4th gear is what, like an extra 3 secs to up the rpm and change gears?

I do think that the cat temp does cause the car to change the timing/fuel.

Im gonna try to get a hold of a scanalizer, so I can monitor all that stuff AS i dyno, and see whats going on.

KYLiquid

for the people that have dyno'd, where do you pickup the RPM from? Also where should I start the sample.....3krpm, 4krpm......

Aseras

Hey KY dyno'd my car @ rogue racing as well at the sunday meet. made 178 HP and 130 tq IIRC ( without WCF weather correction.. it was 93 F that day ).. secnond run did 170hp and 120 tq almost a flat line from 4K to 9500 rpm. I was fighting traction control too, Carlos said there was definatly something wrong, has hesitant acceleration, jumpy rpm's ABS light kept comming on even with DSC held down until burnout light's on.

Next time I'm pulling the relay...

I'll post scans of the dyno tonight..

Glyphon

ky, whats going on with your afr on the 2nd dyno sheet you posted? just more of the shop's broken wb02?

KYLiquid

What gear did you dyno in? also how long was your car off (so it could cool down before the dyno run) what mods (if any) do you have done. With those kinds of number on a mustang dyno, I would imagine you would be close to 200whp on a dynojet....that is REALLY strong for one of these cars, so you must have quite a few mods.

It was also about 90*F air temp when I ran on that dyno, and it had to be at least 85-90*F inside the shop. My car had been runing with the A/C on in traffic for a good 1.5 hrs to get to the shop, and it only sat for about 20 mins till I ran on the dyno, so even my first pull the car was still quite hot.....my car wouldnt even rev over 8k rpm on one pull....more evidence to me that the car was pulling timing/dumping fuel to protect itself.

Anyway, if you did 178hp and 170hp in the same gears (4 and 5) that I ran and you are stock I am pretty amazed......did they get an RPM pickup off your car, they couldnt get an RPM signal on my car so they went by wheel speed, and I know it was about 200rpm off at least........not that it matters much.

I am not sure how accurate their dyno is, and if they changed the calibration for the big rotary meet. A friend has a 01 civic EX with I/H/E, the car stock makes 127hp, their dyno said it did 118 un-corrected and 122 corrected.....i just dont think that motor is making that much power with those mods.

Did they run wideband on your car? They ran it on my (at the tail pipe) so it was after the stock cat. I know on 2 other cars they tested it was giving showing the cars were running 13.5 AFR for most of the RPM range, but later we tested it with a differnt (brand new) wideband out on the road under load and it was reading 11.5 (measuring from the same point they did, so I have a feeling their wide band is off by 2 points, and their dyno if off by a bit........

When I ran on the dyno jet at work last week, I got 185whp in 3rd gear, 180whp in 4th gear and 182whp in 5th gear......again we couldnt get a clean RPM signal so there was no TQ reading. Again I am stock with no VFAD.

Aseras

Here's mine... Just noticed that the AFR is fsked on the 1st one...






04 rx8, 40K miles.. all stock.

4000-9500 RPM for my runs..

KYLiquid

yeah the cars AFR spiked out to like 22, I felt the car bogging down and it would rev over 8k rpm and after about 2 secs of WOT and it not going over 8k I let off......my guess is 1 of 2 things happened : A) the dyno was still sampling when I let off, so it was logging the AFR with no fuel injection (most likley) or B) the wideband came off........

cause if I was under load when the AFR spiked out from 12-22 over 7k-8k rpm I would think that would have been my motor. I was also getting A LOT of blowby out the exhaust....so maby that was also a factor.

I ran a 185 (3rd) 180 (4th) and 182 (5th) on a dyno jet, so it was about 20whp more than my mustang dyno runs (4th and 5th gear) and the car also ran all the way to redline this time.

There was no wideband o2 data and also we couldnt get a good RPM signal so there was no TQ data.

I did notice that the power band is MUCH smoother in the lower 3 gears than the higher 3 gears.......im not sure if its the way the dyno samples data or what.

Does the rx8 have 2 diffent timing/fuel maps, 1 for the lower 3 gears and 1 for the upper 3 gears? I wonder if the tuning is better in one set of maps vs the other.....

Also the car was nice and cool when I did the dyno runs, not cold, but not heat soaked either, as the car got hotter, even in the same gears the power was up to 10-15 hp lower.

Aseras

I dyno'd in 5th, Carlos was the guy there who did mine. It took him well over 20 mins to set it up and we didn't get the rpm, but we did do the wideband. He reset the computer according to the book for the rx8 by wieght and all that crap. etc.. I ran it up to 4K, set cruise control and got it as close as possible to 4K and used wheel rpm to calibrate... after all that on my first run almost as soon as I let off the gas, my temp gauge went from below the middle all the way to hot, and started blowing coolant into the overflow tank... we let it cool down for about 15 minutes.. I was # 4 or 5 and it was over 100 ( 103 in the dash of my car ) in the room. They need better ventilation. That 1 big fan also gets almost no air into my radiator at all. It's too high for aitflow into the bottom of the rx8.

If you can swing it, can we test on your dynojet? I don't mind paying to get a accurate dyno.

KYLiquid

you just brought up something interesting I also noticed with my car, under load the temp gauge on the dash reads normal (just a hair below 12 o'clock) but as soon as I would let off the gauge would spike to about halfway between normal and HOT. I wonder if that is normal, that the car reads ok under load, regardless of the temp?

I also noticed that the fan is not moving much air, and not low enough for the cars radiator.

I will see about how much to dyno the car, we usualy charge by the hour, but Ill see what I can do.

BlueRenesis82

did I see you mention you had OIL coming out of your tailpipe?

PhotoMunkey

It sounds like, with the front wheels not turning, the ABS system is telling the engine computer some funny stuff. I've never heard of having to do a 45 second WOT run to get a dyno reading! Some bright boys need to crack this engine software soon.

If the power of the RX-8 A-spec from Japan is correct, there's more power lurking in the US cars than Mazda's willing to admit. Possibly because of our lower fuel grades here?

KYLiquid

yeah, not oil, but oil smoke....you could smell the oil and see a very faint oil smoke coming out the tail pipes. At first I was thinking it could be coolant/plugs burning up or seals or something, but it clearly smelled like oil, I also pulled the plugs and had a look around, everything looked good.

I agree, I know out on the road when I stand on it....it doesnt take 45+ secs to get from 4k rpm to 8k rpm in 5th gear.......so the car was clearly running differently than when all 4 wheels are turning.

As far as that goes, I am thinking of running the car on a Mustang AWD dyno, the front and rear rollers are linked so they spin at the same speed (so it wont destroy the center diff on an AWD car) so that would mean you *SHOULD* be able to dyno the car and keep the traction control and everything on. I thought someone would have done that by now, but who knows.

As far as grades of gas go, europe and japan (as well as others) use a different raiting system for octane than the US. The 3 grades of gas, although they have different octane numbers, are pretty much the same everywhere (Motor Octane of 87, 89, 93) so 'normal' pump gas is the same everywhere.

KYLiquid

Also dont forget the original 250PS raiting in japan hasnt changed on the car, even though the US number has gone down.

1PS = 0.9863201652997627 SAE HP.

so 250PS = around 245HP......

add in the fact that the SAE just put into effect NEW raiting method, to give a more real work estimate of power. The RSX type S was rated at 200hp from 02-04, in 05 the motors compression was bumped up .1 as well as new ECU programing and raited at 210hp, for 06, tested under the new SAE method....the same 05 (as an 06, mechanicaly the same) is rated at 197hp....a 13 hp loss (or more acurately the motor was over rated by 13hp) so that means the 02-04 that was rated at 200hp was really making more like 187. Anyway....just trying to show that its all about how the car was tested.

Some manufacuters will do what they can to round numbers up, some will also round numbers down for advertising.

The Viper was rated at 500hp/500tq.....cause it fit into the '5 5 5', 500 cubic inches, 500 horsepower, 500 ft/lbs tq. With the new raitings its something like 515hp/520tq.....

BlueRenesis82

That is very weird

KYLiquid

why do you say that. I have never noticed oil smoke from my car before, but I have seen other rx8s (as well as other rotarys) give out a slight bit of oil smoke on startup (cold) as well as a bit on a dyno....sure some of these cars had no cats, but even with a cat, i would think you could still get some oil smoke out.

I know the OMP is tied to rpm, is it also tied to load or temp? Could it pump in more oil if the car was running hotter.

I did notice that my oil was full when I started the day. It was about a 30 mile drive there and about 30 back, as well as about 10 miles done on the dyno itself. It was a hot day and I drove the car pretty hard, I used about 1/8 of my oil just that day.

What do YOU think is going on?