23 Sep 2010

The big day.

Towing anything through Los Angeles is always stressful, at least for me. Pulled in about 30 minutes before the appointment time which worked well because the guys who had reserved the slot before me didn’t show, so they got an early start on my car.

Churches used a dyno called a Dynapack, which allows applying a load at a fixed rpm, rather than the drum-type dyno which counts on speed changes to establish a load. The Dynapack is great for setting things like cam timing, or anything else requiring the engine to be held at one speed with a given load. The entire process of tuning an engine – Hondas at least – takes anywhere between two and four hours, depending what needs to be done and if anything unexpected comes up… which it did.

Nothing really bad happened, but it was embarrassing: the intercooler hoses blew off, the transmission oil drain plug tried to unscrew itself, the gas pedal tack-welds broke – twice, the idle air valve disassembled and destroyed itself, I misplumbed the wastegates and blowoff valves, the knock sensor was acting up, and I came home with two bolts in my pocket from the engine… somewhere. I’ve got no one to blame but myself, not double-checking that everything was tight first. All the guys there were very patient, but it was still humbling.

Anyhow, how did it go? About as well as could be expected. Daniel did many runs as part of setting air-to-fuel ratio, ignition timing, VTEC crossover rpm, and cam timing, both high and low cams. The magic figure can be found in the last photo, 409.5 hp, with a very gentle and wide torque curve, a lot like a V8. Boost came up fast to 6 psi at 2800 rpm, then was a straight line to 9 psi at 8000 rpm. The dip at the top end is because only one wastegate was properly plumbed; that’ll get smoothed out after the plumbing’s taken care of.

I’m going to have to read up on why the knock sensor was picking up so much knock – which appears to be completely false readings. They tried substituting some 109 octane racing gas, which acted exactly the same. For this reason I think they were a bit nervous about pushing it as far as they could, but I’m fine with that. I wanted a smooth torque curve and not a high rpm screamer, and it turned out great – embarrassing things aside. I’m beat; towing three hours back through rush-hour traffic sucks eggs.