I think the plot is over-smoothed so it hides the dip since that is notoriously difficult to tune out and I doubt it would be magically missing from my car.

My redline is 7200 and we were running it to redline, so I don't know what the issue is. Either the dyno operator wasn't holding the RPMs at the right spot before the pull started, or my power drops off precipitously, or the operator was letting off too early, I'm not sure. Nevertheless, I'm not super confident in the graphs and I'd like to get the car on another dyno for comparison. Also, I've moved recently so I need to find a new shop so I can get a new "baseline" for the car before I do the next round of upgrades.

The dyno was a DynoCom unit, which I've read tend to read a bit high. I bet if I put my car on a Mustang or Dynojet it would get something more around 530 at the wheels.

No, I have these ones: http://www.autoatlanta.com/Porsche-9...FVD123023.html

"The factory k24 OEM turbocharger compressor housing is re-profiled and the compressor backing plate is modified. This is done to replace the factory compressor wheel with a larger, modified compressor wheel. The larger wheel is also lightened which allows the turbo to flow a larger volume of air (more power), and aids in quicker spool up, better throttle response and acceleration.

In addition we increased the size of the inducer and exducer to compensate for the higher volume of air traveling through the compressor. The cold housing inlet is 53mm and the cold housing outlet 42mm while the hot housing inlet is 45mm and the outlet is 80mm!"

I'd put it on a dynojet which is probably the most popular dyno. I had these same K24/26 turbos years ago on my RUF. That is what RUF used at the time on their 550 RTurbo builds. They were great turbos, very linear and were at 1.3 bar by 4000 rpm. Pretty much held that to the 7200 redline, maybe a slightly taper off to 1.2 bar. This was on a stock block 3.6 with a RUF intake manifold and intake pipes.

Had my car dynoed this week.

Made 525hp / 785Nm @ 1.1 bar on 93 octane (European 98 octane) and 568hp / 840 Nm on E85. These are estimated crank horse power. European dynos tend to read a bit lower than the US dynos. Looks like the 575hp posted on the topic originally was pretty spot on. Was hoping for over 600hp but turbos didnt make more than this.

Best quartermile on Dragy with E85 the car has done 10.94 @ 129.5mph, 100-200km/h 6.86 secs and 0-100km/h 3.38 secs.

My car is a Tiptronic.

On the dynosheet below you can see the spool advantage of the E85 and you can really feel it on the street.

https://cimg2.ibsrv.net/gimg/rennlis...0f6310cfea.jpg


Mods on the car are:
-Unmodded K24's
-Fabspeed exhaust with HJS 200 cel cats
-1200cc Bosch EV14 injectors
-Walbro 450 with radium adapter and pump power is relayed straight from the battery
-High flow intank check valve
-Fender intakes
-GT2RS intercoolers
-710N diverter valves
-Cobb Accessport with Maffless tune by EFY Engineering

Fueling is on the on the limit with E85 and fuel pressure drops a little on higher rpm. I think fuel lines are needed and/or 525 pump.

Is the car tuned for E85 too?

Yes there is timing added on the E85 map after 4000rpm and of course fueling tuned for E85.

Did you upgrade your fuel pump and fuel injectors?

The whole setup reads on my post if you look more closely.

Order of magnitude what are the parts cost if someone wanted to DIY ~550 HP at the wheels? And is there anything about that journey that could not be reverted to stock on sale if so desired?

Maxing out K24s with reversible mods is definitely doable. Some of the items would be quite a bit of work to go from though (in terms of hours of effort). The big one I can think of is the clutch, which is easily reversible, just a lot of effort).

Curious as to ballpark cost to get to 550hp at the wheels. And what is stock HP at the wheels, assuming no boost leaks, etc.?

would OP mind posting some videos of some pulls on the street and dyno? curious as to what a modded tip sounds like :)

Heres a couple of 100-200km/h runs on E85. Not the best times as it was very hot outside and car was heat soaked. Ill take some new ones at some point.

Set of K24's, UMW's 1 bar wastegate kit, 5 bar FPR, Cobb accessport, custom dyno tune. That's what it took for me.

If you’re interested, I’m selling my full SRM K24+ turbo, fuel,
and intercooler system. Good for 800

Unmodified K16s can make 550+ on E85... K24s should be able to do a bit more imo, but if running out of fuel that will obviously limit what you can do. The K24 powerband is way way nicer than the K16 one.

I made 565 whp/587 wtq and dragy 60-130 consistently in the 6.4-6.5 second range before I upgraded turbos for reference.