Tuesday, September 18, 2012

2100 EFI Running-In report

All good so far. A few self-induced moments of anxiety - mostly caused by yours truely wiring the thermo fan to run in reverse and hence sending the temperature soaring when it was running. Easily solved but I still think the fan is too large for the application - it pulls 19 amps and is larger than the radiator is tall at 16"! It causes the idle to stumble when it initially kicks in which I have fine tuned and mostly eradicated but the ultimate solution is a two speed 14" fan which is in the post.

Retorqued the head and reset the tappets on saturday. I was impressed with the headstuds - they all needed exactly the same amount of re-tensioning at 45-deg. They are torqued to 80lb/ft (ARP 206-4205). Tappets are set to 0.018"

The engine is running very well - both torquey and revvy. From cold you can here the forged pistons - just a gentle slap but after about a mile they are silent.

The power/torque goes absolutely bonkers at 4500-5000 and will rev to 6500+ with a mad snarl and ever increasing urge. I have been a little gentle at these high revs (only about 93MAP) and haven't hit the limiter (set at 7300rpm). I have the mixture set for 12.7 AFR full load and currently using 32 deg advance.


This engine is running a hybrid GTT 42A cam that gave great results in a TR6 and it also seems to really work well in the smaller engine. Driving to work and not using more than 3500rpm it just feels like a normal engine - no hissy fits , no flat spots and good torque from 2000rpm. As you build the revs the power just builds progressively until the step change at about 4500 when all hell breaks loose.  Got a few looks yesterday of extreme puzzlement as the staid yellow saloon with an exhaust note like an pre-war ERA howled past.

Need to get another couple of thousand kms on it (about 600km so far) and then I'll try it on the usual dyno - should be interesting  . Using the car everyday now which soon piles on the miles.