Waiting for sound/video clips... :stickpoke

I'll get you some tomorrow moroning, pending not alot of snow I'll be on the dyno at 9:30am.

oops i didnt know that I wasn't allowed to put that down.

Polak was just on the dyno with his RB system. It made between 172 and 189 (compare this to 186-192 with the TXS system on Armaant’s car) over the course of 6 runs. His car is having the race pipe swapped in now. One point of clarification on these results. Armaant was using 89-octane, Polak is using 93. The power curve between the two is slightly different as Polak makes power earlier in the curve and then drops off. Armaant’s curve didn’t really do this in either the stock or modified condition. My guess is that the extra octane allows for some additional ignition advance earlier in the RPM range which broadens Polak’s dyno curve in comparison to Armaant. We are now trying to fit our race pipe to Polak’s car, but are running into some technical difficulties since the RB cat-back’s flange necks down to less then 3 inches. We are going to attempt to swap our mid-pipe out so the RB guys can still use their muffler, but I am not hopeful that this will work. I’ll know more shortly.

good job, now all we need is results on a turbo car. I hope you guys are working on a turbo kit or Greddy upgrade. show me the power!

The car is crying for a turbocharger as 130-140 ft/lbs is just doesn't cut it. The car handles so well that it’s a shame the car is underpowered from the factory. It would be nice to give the car at least as much motivation as my Elise (Armaant can attest to what that would feel like as he drove it while he was here), but an even better goal would be to make the car accelerate somewhat like one of our stage 2 STIs (Armaant got a ride in one of those). I’ve driven a lot of cars, and own one of the best handling cars in the world, and I am still impressed with the RX8. I just think it needs a little more go.

We’ll start with a small and manageable turbocharger and work our way up from there. I’d hate ruin the balance of the car by adding an overly large turbocharger.

Update:
The RB cat-back will not fit with the TurboXS race-pipe. We are just going to swap the RB cat-back out for the TXS cat-back out and continue our testing.

-Nathan
www.turboxs.com

Umm a few things...first my next car has to be the elise...I'm not even going to begin to describe how amazing that car is i'll call it a mini ferrari and its like sex (if you havent had it its hard to describe how it feels). The sti that nathan took me in though seemed alot faster then even the elise even though the sti was mainly on straightaways... I we could get an rx8 anywhere near the acceleration of that sti and maintain our handling capabilities then I doubt anyone would have reason to complain about anything...or buy anything else for the car. Another cool thing i saw in the sti was a meter which i believe(correct me if i'm wrong) shows you was A/F ratio is being used at that moment based on throttle.

TXS Exhaust system =188 to 193.9 hp
RB Exhaust system = 172 to 189.

you guys should find a car that is more consistent on the dyno using 91 octane or better. I've never seen a car bounce around like that.

We've tried 3 cars (on two different dynos) and found the same inconsistency. Of course when you do 6 run sets, you'll get some differential between the runs. I’ll have a bone stock car on the dyno this Thursday. I suspect it will show the same variation.

the inconsistency is well documented, nothing new here ...

Polak's car made a consistent 196-197hp with the race pipe. His gains at redline were close to 15hp. His power curve is weird. It flattens out around 7k and holds even to redline. Armaant's car made peak power at redline. Very odd... 10hp over his RB system is still pretty impressive.

If I were a shady marketing type I’d plot the high 197 vs. the low 172 RB numbers and show 25hp gains with the swap to the TXS system. However that’s not the way we do things here.

-Nathan
www.turboxs.com

peak at 7k and flat means no VDI opening

Interesting, I wonder if Polak knows this as that would explain a whole lot about the differences between his car and Armaants.

-Nathan

Mine's crying for a supercharger, thanks :)

A supercharger would be a nice addition (I want one for my Elise) but last I checked we were not superchargerXS. ;)

Admin... did you get my email about being a site vendor?

-Nathan

Polak's results were also on a dynapack dyno correct?

yes

Yes.

nathan can you explain the set up for running on a dyna pack? i actually emailed the company awhile back asking some thigns but they never answered. for instance on a dynojet you have to set up the dyno software to understand that you are running a rotary so it interperets the rpm signal correctly.

how does the dyna pack do that? do you have a rotary setting?

thanks
charlie

for those who dont know dynapack is th ekind that bolts to the hubs. go here http://www.dynapack.com/dynapack.html then click dynapack for more detail

Charlie,
The Dynapack system uses optical sensors in each hub and the gear ratio being used to determine the RPM of the flywheel.

Our dynapack, when you first load up the software, defaults to 3.8 as that's the gear ratio of the first customer folder we have on the machine. For the RX8 we've been testing in 5th gear so you would enter that ratio (1:1) multiplied by the final drive ratio.

If you look at the plots Mark posted earlier in the thread you'll notice that they have 3.8 listed. This is because when he loaded the RX8 plots for comparison (note that all dotted lines are comparison plots while solid lines are live runs) he didn't overwrite the current dyno setup since one of the other shop guys was using the dyno at the time.

With both RX8s we used a 4.440 ratio. We then entered a 4 second settle time (the dyno holds your start RPM for this length of time before releasing the hubs to start the run) and a 15 second ramp time from 2000rpms to 8900rpms. Running the dyno this way causes it to make a controlled RPM sweep. We can also perform a step test, or even hold an RPM (or speed) consistent and vary the load on the motor while the dyno generates a real time torque output. This is especially useful for data logging stock ECU trends or for tuning stand-alone engine management systems.

-Nathan

see thats a much better way than with the plug wire signal pick up thing that the dynojet uses for rpm. when they have trouble getting the signal even slightly it throws off otherwise good runs. plus if they dont pick the right setting in the software(say leaving it set for a 6cyl) it throws your numbers way off.

thanks for that nathan.

did you actually post Mark's(polak) runs? i dont see them

No, I have not. When I was talking about "Mark posting" I was referring to the owner of TurboXS who posted the dyno plots from Armaant's car earlier in the thread.

The dynapack RPM method does make a lot of sense. The RPM pick-up on a dynojet can be a real pain.

-Nathan
www.turboxs.com