Quinny

I am not sure if this is really the best place to post this question, but I would like to know how a dyno can read differently from another. My understanding is that a dyno uses calculations based on variables such as torque, temperature etc. So, if everything is done correctly (i.e. sensors in the same place, car strapped down correctly etc), how is it that one dyno can read differently from another? I realise that there are environmental factors (temp, humidity etc), and they will make some difference, but they are still giving an accurate figure based on the conditions.... Maths doesn't lie, if the same calculations are used, and the same testing procedures are used, then the cars should get similar outputs.

I am pretty handy with Excel, I will try to put something together.

I have updated mine, it is pretty rough given the difference in scale, but it is close enough. Power_Curve_XL_Sheet.zip

I suspect that the 125kw figure was done on a lazy dyno. My mates Commodore ute, with a 5.0L V8 - 165kw at the fly from factory, made 127rwkw totally stock, including exhaust. And I have seen countless other 165kw 5.0L Commodores make 125-130rwkw. Now, the R33 GTS-T makes 187kw at the fly from factory, so surely it must make a little more than 125kw at the wheels, given basically the same drivetrain as the commodore (i.e. manual gearbox, RWD, LSD etc). There is no way to tell which dyno is "accurate", so this conversation is kind of leading itself around in circles.

Thanks mate. I was thinking about 160rwkw, but I suppose that the lean mixtures will help a bit. I am not sure if the ECU has been played with, the rev limit is still set at 7000, apparently it is pretty common for re-tuned ECU's to have the rev limit bumped up. I had a look through the Dyno thread, I saw that there is a few cars running 12.5 AFR to 12 at WOT, so I don't think it is dangerously lean, but I might get the fuel pressure checked anyway and get an SAFC to sort it all out. I don't think I will worry about the PFC, I don't think I will need it with the mods I have in mind.

As mentioned, they are attracted/dazzled by the light. One method you can use, but it takes balls to do on a dark country road, is if you see a roo on the road, turn your lights off for a second, when you turn them back on the roo *should* be gone. I have seen someone do this before, and the roo got out of the way as soon as the lights got turned off, but I have never tried it myself. Disclaimer: I take no responsibility for what happens if you try this. Although I have seen it work before, it is no guarantee that it will work every time.

This was explained before. The sensor failed during the second run causing it to go into open circuit mode and read 230 degrees. As a result a correction value of over 30% was applied. Meaning that the run was not a record, and should have been between 1300-1400hp. Still good for an untuned car on a run which was cut 1500rpm short. Apparently Eddy is going to tune the car and re-run it and go for the record again.

Come to think of it, I suspect that the ECU may have been remapped, the boost curve and AFR curve were quite smooth for a car that has a stock ECU, especially compared to other AFR lines I have seen. If it has been, I suppose that may account for a little more power too. The AFR's are a bit lean, is there any danger that the car could ping under any circumstances? What can I do to avoid this?

I watched the guy set it up, the bonnet was closed, the IT sensor was hooked on to the wire mesh on my pod, so I don't know why it would read high. I know that the AFRs are a bit lean, I suppose they should be at about 12 or a bit below for the whole run, but I wouldn't think 12.5 in the mid range should cause too many problems (unless I get some bad fuel and a really hot day) - but I could be wrong. No idea about the ECU, the car is exactly how I bought it, I have changed nothing. I know that dyno's are a tuning tool, but from experiences others have had with these guys, apparently their dyno is pretty close to other workshops around, which is why I was a bit surprised.

The car uses the stock 2 stage controller, max 7psi, dyno confirmed. It is possible the ECU might have been retuned, but it is definitely the original ECU.

The AFR didn't seem too lean, it was at about 13 at low revs - off boost, then steadily dropping to 12 higher in the rev range. I am not sure how "happy" the dyno is, I have known a few people to get there cars dyno'd there as well as other places, and they reckon there is bugger all in it. I had my V8 ute dyno'd there a while back, and it made less power on that dyno than another DD dyno I previously ran on.

I am not so sure, I got mine dyno'd yesterday, and it made 178rwkw, my only mods are turbo-back exhaust and pod filter. I have stock computer, intercooler, boost. Mine is also a 96 model.

I notice that the AT is 10, IT is 18, I don't think it was 10 degrees at 11.30 on Saturday, but I suppose it proves that the pods pick up hot air from the engine bay. I don't think that a gap of 8 degrees would mean much correction value though.

1996 R33 S2 GTS-T. Stock apart from turbo-back exhaust and HKS pod filter, and I mean stock. Stock turbo, boost, intercooler, computer etc. A:F Ratios between 12 & 13 whole way through. 178.2rwkw.

I got my R33 GTS-T up on the dyno yesterday to see how she would go before I put the boost controller and FMIC on. I was a bit surprised at the result, I was expecting around 150rwkw, 160 tops. I never expected to see this. I had a look in the dyno thread, and there aren't too many stockers in there to compare to, and none have a graph that looks like this, hence the new thread. The car is dead stock apart from a turbo back exhaust, and HKS pod filter. Everything else is dead stock standard. Standard boost, computer, turbo, fuel system, intercooler.... everything. The graph doesn't have A:F Ratios on it, but they were between 12 & 13 the whole way through. I notice that the power curve looks a bit wierd too, but I have noticed that alot of Skylines have sort of strange power curves. Does this look right for a basically stock R33? Any other info would be appreciated.

Any chance I could get my name changed to BlackR33 ?

That's right, they cracked the block on the old motor, and the new one was only put together a day or two before the event. I just heard that Eddy will be running the car again probably today or tomorrow to "see where it's at". An interesting point though, is the fact that the power run was cut short by 1500rpm because the twin-retarder dyno was maxed out and displaying an error message. That didn't happen with Brett Waines 1470rwhp run, and no one seems to be able to say what the limit for the dyno is, but it stopped at an indicated 1895.9hp.

I am known as DARE U on the Street Commodores site, you will find several posts by me on there, that is pretty much where I got the info (and the pics) for this post. There is a report on the dyno dynamics website in regards to this, until yesterday, they thought it was a new record, and they don't make any attempt to estimate what the figure should have been, so I am not sure where "Do It Again" on the SC forum got his info from. Here is the link for the official Dyno Dynamics response http://www.dyno.com.au/news.htm#june01_Altomak And I agree, world record or not, it is still a valiant effort for a car that is not tuned on an incomplete run. Good luck to him, I hope he does back up his figure and breaks the record.

The quote that said "get your facts straight" was quoted by me from the user of another forum who was a competitor at that show. That quote was later retracted by that person after trying it on his own 700hp VL. I provided that quote after you asked the same question I did regarding the inlet temp figure. I was simply giving you the information that I was provided with, I never said it was gospel, I never said you were wrong.

The facts were straight at the time. DD said that the figure would not be affected, so it was left as that until today. I also said, I am no expert, I was relaying information from someone who was there as a competitor. I also mentioned that I thought that the figure was suss as well. But i do believe that this thing will make more HP than the "corrected" figure that DD calculated. And for the record, I was not trying to "defend" anyone or anything, and I didn't "have a go" at anyone. Don't shoot the messenger mate.

Dyno Dynamics has released their findings. The figure was inflated due to the temp sensor failing and going into "open circuit". They have recalculated the figures based on a 60 degree IT, which came to 1434.6, but still allows for 10% correction. With no correction value for IT, makes the maximum power 1304.2. Still not bad for a car that is not tuned, and the run was cut short. There will be more from this thing yet.

I agree, Ferraris aren't really known for their driveablility, but I find it pretty hard to believe that a Clubsport which will do 5th gear burnouts with traction control on could be more streetable than an F355.

PM sent mate.

It has been confirmed that the car was untuned, and that the dyno was maxed out, so the power run was cut short. Apparently, Eddy and Dyno Dynamics are keen to back up this figure using a better dyno and the correct IT figure. Should be interesting. 39psi isn't really that much when you are talking 1895hp.

I agree, tune it for street fuel, and set the correct inlet temp, and it probably won't be anywhere near as high. However, I think that there is alot more left in this engine, despite the fact that the figures may be inflated, the power run was cut short. I reckon a genuine 1500hp is likely once everything is sorted, although, everyone has said that Eddy will back up this claim, so maybe Eddy knows that this thing has 2000hp in it. Holden 8s weren't designed to do that, but it goes to show what the dinosaur pushrod V8 can do when stretched to the limit.