Hello!

I recently tested the do88 intake pipes for 997.1 on my 2007 tiptronic turbo on a SuperFlow SF880E rolling road dyno here in Sweden. I thought some of you might be interested in the results.

My car runs on Syvecs S6+ standalone ECU and I thought that this is important since stock ECU will lower boost to compensate for potential additional airflow. The adaptations in the Bosch Me7 are quite impressive actually, but not so good for dyno comparisons on a particular boost level.

Car specs:
2.5” exhaust with 100 cells catalytic converters. Muffler with internal X-pipe (ferrita)
BMC airfilter in stock airbox
300 kPa MAP sensor after the throttle. Stock TMAP is still used for air charge temperature.
The rest is stock (engine wise)

Fuel:
RON 98 octane. I did refill at the same gas station both times with 2 days between refills/dyno sessions.

Tune:
The engine is tuned by me, but I have had great support from Ryan at Syvecs. I use the Syvecs knock control as an aid and safety feature, but I do not intentially leave it in closed loop knock control as OEM does. With this said, the actual numbers could have been higher, but I was more looking for the relative difference rather than the absolute. My ignition timing, including temperature corrections, comes from road testing.

The tests were performed two days apart and unfortunately it was colder the second time (when the do88 pipes were tested). This affects the results, especially on a petrol fuelled engine with stock charge air coolers. I knew this was a risk for a good comparison so I also fitted two thermocouples into the compressor housing on the left turbo charger. I measured before and after compressor and for a given absolute pressure after the throttle I expected to have lower temperature increase over the compressor if I switch to intake pipes with higher flow, i.e. less pressure drop before the compressor inlet.
The dyno cell had two fans blowing on the side air intake for the intercoolers and we tried to wait until we had stable conditions before each pull.
Unfortunatley I was not allowed to drive the car on the dyno and the operator kept going to kick-down giving that the car will actually shift instead of going to my set rev limiter at 7100 rpm. He also managed to get some slip in the gearbox so lower engine speed is a bit off. We actually got a bit higher boost with OEM due to different driving pattern which is shown in the torque levels below.
All measured data from the SuperFlow dyno is corrected for ambient conditions.

Conclusions:
The power increase is quite nice, but some of the performance gains might come from the lower ambient temperature.
If we look at the delta compressor temperature we see that the do88 intake pipes works really well. 3 degC delta with 2,4% more airflow. Added airflow on a compressor close to the choke line usually drops in compressor efficiency giving that I would expect to see even larger difference. We also had 1 kPa difference in ambient conditions which we can assume translates to 1 degC extra temperature increase over the compressor. From my experience with OEM turbo calibration I would assume that 5 kPa is a reasonable difference in pressure drop with the do88 intake pipes over OEM. This is great results and (almost) free power for the engine.

(I tried running 1,3 bar but ran out of compressor at higher engine speeds, so I skipped this. I might add some extra midrange boost now, but for comparison I thougt it would be best to keep it to one boost level only. I had over 200 degC after compressor running 1,3 bar )

 

Very good info and thank you for sharing.

It's nice to know that fitting these pipes there are some small gains to be had!

 

Thanks for the data. I'm not surprised by the 200C, if you plot data on stock compressor or calculate the comp eff at high boost level / high engine speeds we are in the dumps eff wise. You can also tell by how much its closing the vanes. Terrible comp eff consuming a lot of turbine power thus closing vanes to get expansion ratio up to make turbine power. Bad news everywhere from a turbo match perspective lol. But of course we all need to remember it was matched for less power...we are the ones running it outside the design targets.

 

How would one counteract the reduced boost after installing the intake tubes? Would a simple tune from someone like FVD or a custom Cobb tune do this?

 

very nice data. +rep

 

Thank you guys!

To counteract the tune needs to be adjusted, yes.
I guess a custom COBB (or similar) tune will do this.

 

Thanks for sharing!

 

Those look like substantial gains!

Looks like I'll be buying some! How was the install? Do you hear the Turbo whistle more with these?