More 930 Headers - and now for something completely different ...

[Midlife930]

Hi,

Not sure why I can't find a shot of the intercooler installed but here's a cell image in the kitchen. I sent my Kokelin to Bell with a sketch or two and they built a bolt in. All arranged by Todd at Turbocharging Dynamics who I have worked with on BMW turbo systems for years. He spec's and supplied the turbo that is on Brian's header system.

Dave

[Midlife930]

Pulling this old thread back up as I have finally had the opportunity to get the car on a dyno with Sasha Anis of On Point Dyno
OnPoint Dyno
Sasha is a great guy who knows tuning and is easy to work with.
I like the idea of a hub dyno much more than strapping the car to a roller. Easier on the equipment more accurate and less dangerous.
I have moved to a 0.9 bar spring set up which put me around 13 psi on Sasha's machine.

Dyno hubs on the car



On the Dyno



Sasha installed his Knock Ears to ensure no knock then took my tune of around 440 hp and 355 torque to 460 and 373. Apart from peak numbers he flattened and raised the torque curve through the entire power band and brought boost in sooner. For a track car that sees extended periods of full boost I am very happy with these power levels.






Then cooling her down




Looking forward to Watkins Glen this weekend,
Dave

[Tippy]

That is some strong numbers for sub-1 bar of boost. Congrats!

3 questions:

1. What are the turbo specs
2. What RPM are you seeing full boost
3. Tuner trick to bring in boost sooner?

I've read debates between running lean or rich right at zero vacuum, but everyone seems to agree on a slight timing retard at the first onset of boost to lug the engine harder than normal to get it spooling.

Curious if the tuner made mention of his technique.

[mnez]

Nice write up Dave.

[Midlife930]

Thanks and thanks.

1. GT35R on a T3 with the largest A/R compressor housing available from Tial
2. The yellow line on the chart is boost, you can see the ramp and in by 4,000
3. Sasha lowered fuel as I was a bit rich and added a few degrees timing.
in his words, boost just came in quicker as the engine was happier.

He spent a lot of time at mid throttle mid power in the middle 300's getting the mixture right, then moved to full power pulls & then timing. You can see from the lap numbers he only did 6 full power pulls after all of the mid power work. The goal was on track power delivery for predictability not hero numbers. Hence,, the time spent below full power which of course you don't see in the chart.

Dave

[Tippy]

Oh yeah, WOT is very little tuning, most of the tuning is below WOT.

That is a big turbine, didn't realize Garrett's ran that big.