Hey all! First things first – I got a new job and have been working a lot of hours; I’m going to try to get back to 1 video a week as soon as I can. Thanks for being patient.
I also want to thank Toby @ Advanced Engine Dynamix for letting me use the rollers for a few hours and giving me so much good advice for my builds.
Stock ECU vs. Megasquirt
Here’s a Virtual Dyno (very accurate program btw) of MS at 4psi vs the stock ECU at 4psi. These are the TORQUE curves. The reason for the low end power being so weak was that I had no ignition timing control on the stock setup, so I just ran the CAS at 5 degrees base timing for safety which killed the spoolup and low RPM power. Up top, the stock ECU doesn’t really limit anything as long as you keep your AFR and ignition timing in check. By the time you buy ignition control for the stock ECU, might as well have just gone MS in the first place which is what I highly recommend. It’s daunting at first, but you learn it and get used to it over time and with practice. Complete build list for B&B (minus the MS).
First up is the bone stock dyno overlayed with the runs at 4psi, 6psi, and 8psi. You can see even way down at 2500RPM before the turbo is “spooled up” the car makes +20wtq over stock. (I forgot to scale the X-Axis on the dynos the same so the shape of the curve may look a little different between them.)
This was one I was really excited for, bone stock exhaust vs open downpipe. No tuning changes (torque dip caused by running lean in the low RPM). I maxed out the stock injectors completely at about 6200RPM.
Another ‘cool’ test: how much power do you lose with the A/C running??? So that’s why the car feels like such a pig.
Here’s my final dyno pull vs. my first 8psi pull of the day. Only difference here was some ignition mapping. I wasn’t able to run too much more timing over the MS base map, but it definitely helped.
Some of you may remember the acceleration tests (and horrible Fast & Furious skit) from the original B&B performance video. Here are the updated results:
Notes: crap tires and stock clutch in both tests.
0-60mph & “Passing Power” (50-80mph in 4th gear) Results:
The Roll Races
A little info about the races: despite having matched or better power-to-weight ratios of some of the cars I raced, the short gearing combined with slow spoolup after shifts puts me at a big disadvantage. This was the same problem I had with the other car, until I swapped in a 3.9 Torsen diff and a Garrett GT2554R. Instantly solved both issues and totally transformed the car.