I've been driving the car, and learning the new engine and new tuning system.
I did a 180 mile drive to Philly and back when I needed some stuff from Bus Depot for my bus project. And last weekend I did a 300 miles drive on Saturday and showed the car at Bug Out VA. I was the only 914, and got lots of questions about the engine.
I did datalogging for the entire 300 mile trip. I'm just scratching the surface of the Terminator X ECU. The engine comes with what they call a "hand terminal" that plugs into the canbus jack. This is a super handy tool that I ignored for most of my break in.
Right now I don't have it run through the tunnel - and that's something I intend to do! Its just too handy a tool not to. Its a data logger, but it also has a gauge cluster so you can see what the ECU is seeing.
I also bought a canbus splitter so that I can plug my laptop into the ECU and leave the hand unit plugged in.
With a little over 600 miles on the engine, its time for and oil change and valve adjustment. And I need to get the data logs back to
@eric_shea for evaluation (which I will do when the CANBUS to USB cable I ordered comes in).
There are a couple things that I think can be improved. the gas mileage is about 18 mpg with me cruising during break in. That MAY improve on its own as the engine tightens up. But I bet there is improvements to be made at idle and off throttle.
There has also been some rev-hang, where the engine will stay around 2000 rpm for a moment when I push in the clutch instead of dropping immediately back to idle. At first I suspected the IAC was adding air - and I think that was Eric's opinion too. But driving with the hand unit in the cabin with me, I could see that the IAC was fully closed. The hand unit is REALLY handy! Playing with the car tonight (and watching the TPS data on the hand unit) I suspect the issue is mechanical and not part of the tune. On throttle close, the TPS was showing the throttle sticking at ~22% open instead of closing. I'm almost sure that is the cause of my rev hang.
The difference between fully closed and 20ish% is under 1mm of travel. It may need a helper spring, or there may be some slight bind in the throttle body sync.
Closing the throttle at idle will hopefully cure the rev hang, and give me a little boost to mileage. I fully expect that this motor should be able to get at least 25mpg when cruising down the freeway.
As to driving impressions - this motor is a beast! I was accelerating up hill in 5th on the freeway, doing well over 90, with head temps that never got over 350 and the throttle was never wide open. You don't need to drop a gear to pass traffic. And you CAN pass traffic.
I've still not done any 2nd or 3rd gear pulls at WOT yet. That will happen after the oil change and adjustment.
There is NO drama starting the car. Either cold or hot, it starts right up.
If you are thinking about getting one. STOP THINKING. Call PMB and get the ball rolling.
Zach