Project GD STI: Making More Power with Cobb Tuning and Precision Turbo Part 2!


The new Cobb 3 port solenoid bolts right back in the same location as stock and plugs right into the stock wire harness. 

Howard replaces the 15 PSI actuator for the 20 PSI part and sets the wastegate valve cracking pressure to 25 PSI like before. 

Cobb's calibrator extraordinaire, Mike McGinnis, had taken all of our mods into consideration and developed a drop in tune for our Acess Port so that we could get our car started.

We ran over to Cobb Installer AntSpec in nearby Fountain Valley to use their AWD dyno to confirm our tune. 


We did a few test runs with Mike to see how close his tune was to what our car actually needed and found that he was really close right out of the box!

A common misconception is that flex fuel is like having two tunes, one for E85 and one for gas, but the COBB system is set up to allow a single tune to comprehensively allow control of fueling, timing, boost, and valve timing related functions over the full 0 to 100% range of possible ethanol content. For example, Cobb's fuel controls allow adjustment of cranking, post start, hot restart, tip in enrichment, closed and open loop fueling over all engine conditions all based on ethanol content.

The entire flex fuel system uses custom code that COBB wrote, which did not exist on the factory ECU, and it allows the car owner to pump any combination of E0 or E10 gas, E60-85 from the pump or even E98 from a drum with no worry about what the resulting mixture might be.

When calibrated correctly, the COBB system handles everything for the driver. It allows the engine to run as if you had a full custom tune performed just for whatever ethanol level ends up in the tank from zero to 100%. This is just right for lazy us!

Cobb provides blending control that goes beyond the typical linear control others use because Cobb's calibrators have found that ethanol blends of E60-E70 offer the bulk of the detonation resistance of higher ethanol concentrations, and setups not tuned to their absolute limit can often be run at “full power” at 60-70% ethanol content without having to fully empty their tank and refill with e85. The driver doesn't need to worry that they won't make power or damage their engines if they get “winter blend” E85 which is less than 85% ethanol.


AntSpec's dyno room is pretty state of the art for a chassis dyno.  

AntSpec uses a Mustang Dyno with the room having super high airflow fans that can simulate highway speed air flow and evacuation fans that keep the air supply fresh even with very high powered cars. 


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