pretty good acceleration above 200! So how much boost is used in your car?

 

1.3 bar max on top. This stage was in the middle of the development. The final version runs 1.4x. Anything more just adds to heat on this car.

 

Do you have logs worth publishing with RPM, speed, IAT, EGT and boost?

 

When I compare my old logs I think I noticed the same thing. i.e. the performance didn't change much from 21.5psi to 22.5psi, but probably generating a bit more heat. I have been logging "modeled egt" in the Cobb AP and assume it's the same as what Durametric logs. Is this the same data that the ecu uses to determine when to pull timing etc...?


Are you running tapering boost or the same boost at all rpms (above 4k or so)?

 

Are you running stock 997.1 VTGS?

 

Modeled EGT is useless. It gives back way too low temperatures. I was logging the real temp sensors (bank 1 and 2) with PIWIS. These are used for engine protection.

I am running 1.3x bar for rod protection and keep the torque pretty straight. When the torque starts to fall I raise boost and keep it at the chosen max value until RPM limit.

Even 1.4x bar is pretty much for this car or better for these turbos. It's already pushing the envelope.

 

No. GT2 hot side plus 47.5 mm compressor wheel (we measure the intake here)

 

Interesting. Are you tuning yourself or is someone sending you a tune? We have GT2 hybrids and are experimenting moving boost from 1.3 bar to 1.4 bar. Does it all hold together at 210mph in terms of IATs and EGTS?

We've only managed to run our car up to 150mph so far but plan to take her up to Bruntingthorpe and log and VBOX the car but even at 150mph quite large difference in IATS over old tune running 1.3 bar.

 

For reference

 

Bogg can you still upgrade the hotside to GT2 spec on your 68mm? I think you should go down this route if you maybe can. Also just converted 22.5 psi to bar and it equates to 1.55 bar! This is far too much IMO with a large compressor wheel like your turbos have.

I know you hardly ever take her above 200kph but it would be nice to smoke that Corvette at your one track event a year. GT2 hot side barely larger but every little bit helps

 

I tune myself. Above 1.2-1.3 bar nothing holds together on these VTGs That's the reason why all these 7xx or even 8xx hp 997 VTGs make me smile.

I guess you will see the problems coming unless you guys know something to do that I don't.

 

Many thanks

 

Everything is bigger in Amerika...

 

Certainly more snake oil and tall stories

 

lol


American vtgs are tuned for American requirements, nothing snakey about it. Nobody has denied that high boost is suitable for the 60-130 range but not for the 200-300km range.


As far as the dyno numbers - yeah there are definitely some laughable results. Many of the graphs already have a conversion factor done in order to show the estimated crank hp based on a conversion factor of about 20 percent.


On my dynotune on pumpgas the peak hp and peak tq on a Mustang AWD dyno was around the 570-580 range at the wheels. We had to stop because of some spark plug scatter and my O2 sensors were giving signs they were not quite behaving optimally.


My goal was consistent 60-100mph in 3.0s and 100-200km/hr in high 5s. I will use as little boost as possible to do it. Will dynotune a bit more once plugs/coils/O2 sensors changed.