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I can give an example.. but we will protect the innocent. It can be more than 10% anyhow.

As one example a bunch of cars that have read 190rwkw.. read about 165rwkw or thereabouts over the weekend on a dynologics dyno up here. And I've seen it before. All dynos can be different, from just a few rwkw to a stack. Even on a different day the readings can be slightly different.

All dynos can be different, from just a few rwkw to a stack. Even on a different day the readings can be slightly different.

Dyno Dynamics have tried to take out the variation and limit the operator influence with Shoot Out Mode. At the very least it shows the settings on the bottom of the print out for all to see. I have used 4 different dynos (in 2 states) with all now running Shoot Out Mode and the power output (same car in two case) was so close it didn't matter. There a still a few "tricks" that the unscupulous operator can manipulate the power outputs with. But many have woken up to the fact that it isn't really worth the heartache when you can so easily go to another dyno and spend $40 to confirm his readings. :Bang:

It's not perfect, but it is way better than it used to be.

Also, I have lost a chunk of power down low. For instance I used to see full boost at 2300 rpm with stock ecu, now I hit full boost a 2900-3000 rpm...

Wouldn't that be because full boost is now 2.5 psi higher than before?

A mate's R33 was tuned to 201kw, then when he went to a diff place it only drew 184kw..so yeh, it can be hard to compare unless you use the same dyno, or Shootout Mode is another way to reduce the bias as Sydneykid said.

Interesting results Robo, personally I would have expected a solid 15rwkw more with the P/FC over a stock ECU. I'm making 186rwkw on the UAS Dyno with the stock ECU (but I have an Ex Cam Gear and the stock ECU, everything else is the same as your setup). With a P/Fc I'm "expecting" 200rwkw, a lousy 14rwkw to gain shouldn't be all that hard with an aftermarket ECU and EBC.

Throw up your boost printout and also the torque printout.

Is the bleed valve even holding 13.5psi? It appears my dual stage is peaking at 12psi (what it is set to) but can only hold 9.9psi (even if we set it to 13psi it still drops to 9.9psi up top).

Next time you head over to UniGroup give us a call (pm me) so I can come and have a look.

Well nothing at first. If it keeps going...

If you've got a good mix of coolant (33-50%) in your radiator and there are no leaks, it won't boil until it hits 120 degrees or more. My last 2 motorcycles have digital temperature readouts for the coolant. The thermo fans don't even kick in until it hits 108-112 degrees, which it creeps up to only when idling. The thermostat usually keeps the temp at almost spot on 83 degrees when in motion.

Once again thanks for your replies..

When I picked my car up after the tune, my bleed valve was holding 13.5 psi and then it droped off to 12 up high.

I do not have a graph of the boost or torque, will have to go back and get it..

All I know is now that I have turned my boost down to 12.5psi (thought 13.5 was too high) It all seems a waist of money after the tune..

I will be looking to buy the PFC boost control system and have it re-tuned with leaner fuel mixtures..

Any ideas where I can go for a good tune in sydney?

Regards

Rob

Ps. A few people have mentioned dynos reading differently. In my case (as you can see on the graph) my previous run was on the same dyno...

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