My 5500ft dyno

[George@BMS]

A few weeks ago I decided to take my car to a dyno day. The altitude where I live is 5500ft and the temperature on the day in the workshop was 95F. The run was done with no cool down on the car and with the hood closed which is not the best for someone with dual cones. Baseline figures on this dyno on the same day for two N54's where 243whp and 253whp. So the dyno runs similar power outputs to the US Mustangs. A ESS V8 made 450whp same day.



The boost was at 16.6psi running 91+meth with full bolt on's accept for stock catted exhaust. The reason I posted this though is the lack of the traditional 4000rpm dip found on the piggy back cars. Does it mean my flash tuner has found a way around this?

As a matter of interest I have the fastest documented car in South Africa with a 12.30@115 done at high altitude and at 102F. This is with full interior on a unprepared runway. The only N54 car that can stick with me if not beat me slightly is a Procede V4 that I brought in for a relative but I am sure he cheats with the boost hehe. The JB3 cars seem to be battling at altitude. We do 1km runs here as well, my best exit is 251km/h: for reference the best chipped 135 does a 234, ESS V8 does 255, stock M3 V8 217

Next steps are the RB turbos and the AE Exhaust that I just ordered from AR Design.

[oddjob2021]

cool stuff George. related to your M drag thread, what kind of trap speeds were they running? i ask because you're right up there with them, is it because of the altitude? what did they dyno on this dyno? and goodluck with your new turbos, keep us updated as you mod

[654]

Nice, now both of you can contribute to the knowledge of how much is the dyno measured gain of upgraded twins

[Terry@BMS]

Chart looks good! Remember at elevation the ECU shifts around the boost and VANOS tables. For example peak boost comes in to around 4500rpm. So you would need to do a few runs at sea level to compare the overall curves that others closer to sea level post.

With our G3 the bump followed the OEM logic but with the G4 we've setup the tuning to smooth it out.

[encinitas]

Thanks for the post Gsmooth! I'm pretty interested in how a flash tune will handle the upgraded turbos. I will look forward to seeing what you guys do to dial in everything once you get your RBs.

[George@BMS]

cool stuff George. related to your M drag thread, what kind of trap speeds were they running? i ask because you're right up there with them, is it because of the altitude? what did they dyno on this dyno? and goodluck with your new turbos, keep us updated as you mod

The best M6 up here has run a 12.6@116. They exit around 240km/h on the kilometer. On this dyno a stock S85 will make around 350-370whp. The dyno I posted is not true reflection of the power I make which is closer to 400whp+.

Thanks for the post Gsmooth! I'm pretty interested in how a flash tune will handle the upgraded turbos. I will look forward to seeing what you guys do to dial in everything once you get your RBs.

The flash tune will handle it fine up to a certain boost level. If the fueling system can hold fuel for the psi I want to run it will be perfect. If meth is needed to supplement fuel we will experiment with a fail safe system that triggers a engine fault when meth flow drops. I am not happy doing this so if there is not enough fuel I will most probably have to go the piggy back route.

Chart looks good! Remember at elevation the ECU shifts around the boost and VANOS tables. For example peak boost comes in to around 4500rpm. So you would need to do a few runs at sea level to compare the overall curves that others closer to sea level post.

With our G3 the bump followed the OEM logic but with the G4 we've setup the tuning to smooth it out.

I have found that the boost is only affected from 1000-2500rpm with slightly more lag. You can see this on the waist gate frequency. Once past that they follow a similar %. Its a different story when flooring from part throttle where the lag is more evident. The biggest killer is the oxygen density drop so a bar up here is no where close to a bar at the coast.

[George@BMS]

Here is a picture of the take off area. 2.1sec 60ft sux.

[Terry@BMS]

I meant, the ECU itself changes it's (stock) boost targets. So instead of peak boost coming at 5200rpm it comes at 4500rpm. And instead of 8psi you get say 10psi. This is of course all stock so with a flash it will follow whatever logic the tuner has programmed.

[Boosted1]

As a matter of interest I have the fastest documented car in South Africa with a 12.30@115 done at high altitude and at 102F. This is with full interior on a unprepared runway. The only N54 car that can stick with me if not beat me slightly is a Procede V4 that I brought in for a relative but I am sure he cheats with the boost hehe. The JB3 cars seem to be battling at altitude. We do 1km runs here as well, my best exit is 251km/h: for reference the best chipped 135 does a 234, ESS V8 does 255, stock M3 V8 217

Next steps are the RB turbos and the AE Exhaust that I just ordered from AR Design.

I would like to hear your input about my situation, http://n54tech.com/forums/showthread...250#post157250 I've always know altitude affects both NA and FI cars, but im pretty confused right now. Cause I feel the car pulling very hard, but not reflected on the strip.

As soon as I get my car back and If you thinks its necessary, Ill send you some logs Terry.

[George@BMS]

I would like to hear your input about my situation, http://n54tech.com/forums/showthread...250#post157250 I've always know altitude affects both NA and FI cars, but im pretty confused right now. Cause I feel the car pulling very hard, but not reflected on the strip.

As soon as I get my car back and If you thinks its necessary, Ill send you some logs Terry.

1. I think your bad times are mainly due to the bad track. We have a similar track up here where the average tuned 335 runs a 13.5. A stock one with a great driver has pulled a 13.2. A lot of times you will not even notice wheel spin and if your 60ft is bad the whole run is bad.
2. If you suspect you down on power run some cars on the highway first stock then with your JB3 working.
3. The JB3 cars have the same problems up here as well, maybe Terry has more insight in the reason to this.

[Terry@BMS]

At elevation the JB3 G3 needs special settings. Basically, out of the box it is set too conservatively at higher RPM at high elevation.

[Boosted1]

At elevation the JB3 G3 needs special settings. Basically, out of the box it is set too conservatively at higher RPM at high elevation.

Oh I see, Im guessing that and the crappy track is my problem... What do you think Terry, should I buy the USB Cable for downloading/changing settings in the G3 or I should just wait for the G4 (since im reading it would kinda solve the altitude condition?)? Im guessing G4 is to be released anywhere before christmass so I'll guess I'll wait. Nonetheless, excellent product T, even at this altitude the torque pushes you in to the seat in such a powerful way.

If you need any kind of beta testing for high altitute and G4, Im in! I have BT tool and wouldnt hurt to have a foreign beta tester!

[Terry@BMS]

Might as well wait for the G4, and grab the USB cable at the same time for updates and datalogging.

[LostMarine]

george. i was just reading your convo on another forum w/ sherwin @ xede good stuff