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We had version 1 and from that found some areas to refine and change, we had to have some custom pieces made to fit everything the way we wanted. Short answer, yes, we're closer, but will still be a few more weeks...
Just a simple question... Out of the box what Percentage VE is Porsche aiming at for their GT3RS? And what number's for VE has Dundon experienced with their modifications without a tune?
Since the car is using MAP, not MAF's it's hard to calculate a gross % VE improvement. We can calculate relative improvements but some of the improvement is from reducing pumping losses, some is from resonance scavenging and some improvement is from thermal efficiencies...
We'll look at getting PIWIS to export air mass to at least get a bit of an answer for you...
Why we have never seen real life pull stoc vs DMS nor Vbox data?
We have had a few customers offer to get vbox data, but they're busy and likely don't want to go to jail. Same thing for stock car vs DMS equipped, GT3 owners take it to the track, not on the street..
We only have one 1/2 mile roll racing competition up here and its about 5 hours away, don't know if I'll be able to make it with starting the shop.
We have given 1/4 mile data, multiple dyno's and customer dyno pulls, been as transparent with our development as possible and given far far more data than our competition.
If there is a chance to get vbox or head to head data we will try, but honestly getting the GT4, Catted 991 GT3/RS , and Catted 997 GT3/RS systems are a priority.
I didn't actually mean that you should provide this data as you have already provided 10x more information on your product than any other manufacturer or tuner.
I was hoping that your customers would do it. If I installed some aftermarket power upgrade that would be the first thing to do. Unless most of people here do this for the better sound result and not the power gains.
To be precise with the measurement one must have Mass Airflow rate and Intake Air Temperature measured at the MAF or the MAP, whichever way one has, and a few other measurements to complete the equation.
Having as much horsepower as they have out of the box, the GT3/RS making 475/500 bhp respectively, with their displacements should be pushing over 100% Volumetric Eiffienecy.
I've been reading where people have a Laptop and an "Auto Tap" to extract the information. But I agree to be safe all lab work should be done on a Dyno of some sort.
Besides I'm talking about VE and not Horsepower specifically and besides the point a VBox could not extract such data to come up with VE.
Probably an obvious question, but what about the 991 GT3 allows you to crank out an additional 20hp with the same setup?
What gains are you expecting with the catted version?
it's an interesting question. All of the modern ECU's are torque limited, meaning they have a model in them that looks at engine parameters and calculates the torque out put of the engine. The Bosch MED17.1.11 in the 991 GT3/RS is very good at this calculation, even with the headers on the car we compared the PIWIS calculated torque to the dyno readout and it was very very close.
We believe the torque limiters between the GT3 and RS are set at similar levels, the GT3 just has more room before they kick in. With the tune on the RS we were able to get the headers much closer to the 40whp the GT3 produces...
As far as the catted version, we learned from our no cat and v1 catted system what the resonance tuning and volume requirements need to look like. We're targeting 25-30whp with the catted system, we may be able to eek a little more out of it, but this is our target with 200 CPSI cats...
In other news, Race headers are in stock ready to ship if anyone's been waiting on the sidelines!
it's an interesting question. All of the modern ECU's are torque limited, meaning they have a model in them that looks at engine parameters and calculates the torque out put of the engine. The Bosch MED17.1.11 in the 991 GT3/RS is very good at this calculation, even with the headers on the car we compared the PIWIS calculated torque to the dyno readout and it was very very close.
We believe the torque limiters between the GT3 and RS are set at similar levels, the GT3 just has more room before they kick in. With the tune on the RS we were able to get the headers much closer to the 40whp the GT3 produces...
As far as the catted version, we learned from our no cat and v1 catted system what the resonance tuning and volume requirements need to look like. We're targeting 25-30whp with the catted system, we may be able to eek a little more out of it, but this is our target with 200 CPSI cats...
In other news, Race headers are in stock ready to ship if anyone's been waiting on the sidelines!
Jamie
Jamie, any further updates on the chatted system numbers and any other improvements for the RS tune?
We've got the GT4 headers mocked up, will start on the catted 991 GT3/RS systems next. For the tune have a few going on customer cars, one in Australia one in the SE Asia, and a few more in the US.
it's an interesting question. All of the modern ECU's are torque limited, meaning they have a model in them that looks at engine parameters and calculates the torque out put of the engine. The Bosch MED17.1.11 in the 991 GT3/RS is very good at this calculation, even with the headers on the car we compared the PIWIS calculated torque to the dyno readout and it was very very close.
We believe the torque limiters between the GT3 and RS are set at similar levels, the GT3 just has more room before they kick in. With the tune on the RS we were able to get the headers much closer to the 40whp the GT3 produces...
As far as the catted version, we learned from our no cat and v1 catted system what the resonance tuning and volume requirements need to look like. We're targeting 25-30whp with the catted system, we may be able to eek a little more out of it, but this is our target with 200 CPSI cats...
In other news, Race headers are in stock ready to ship if anyone's been waiting on the sidelines!
Jamie
3 questions, with your RS headers and exhaust will any CEL lights come on dash? also can you quiet down the car with factory exhaust button?
roughly 25hp gain?
3 questions, with your RS headers and exhaust will any CEL lights come on dash? also can you quiet down the car with factory exhaust button?
roughly 25hp gain?
I have these on the way for my RS.
Answers to your questions: Occasionally the CEL can come on if doing WOT from low RPM's lugging the engine. Doesn't effect the car performance wise at all. The factory exhaust button still works to quiet it down. 20rwhp peak gains, 25rwhp max gains and gains throughout the entire rev range. Hope that helps
06-04-2016, 01:20 AM
