Monday, December 28, 2009

Post Christmas running repairs

Humph was bored after Christmas so suggested some theraputic spannering on the hottest day so far this summer... 40 deg in the shade. Got my diff out... very unhappy pinion... think the quaife might need a rinse out... any ideas if they are easy to take to bits??

Heralds clutch has been dragging badly so out with the box... bit of a heave ho these cast iron lumps.. must be getting old :-( Luckily we have modified the transmission tunnel to get the J Type single rail box out without too much of a struggle.

Monday, December 21, 2009

Megasquirt Update

Well its all a bit of a non-event really.. been driving to work on a daily basis and it hasn't missed a beat. Currently on my second tank of fuel... first one gave 25mpg which included a lot of idling , traffic jams and messing about with tuning the VE table.

I have been using the Megasquirt autotune feature which with a wideband o2 sensor allows you to set a target AFR which it achieves by modifying the VE (volumetric efficiency at the corresponding rpm/MAP point. You then burn the new table values into the ECU flash card whilst still driving. Very neat.

I currently have an AFR of about 16.5 at cruise ~ 14.0 under mild acceleration and 13-12.5 under full power. I need to set up max power on a dyno in the new year but basically economy in normal commuting seem to be high 20's which is just fine - I will start pushing the envelope of economy at cruise using plasma plugs in the new year too... just happy to run about and settle down the basics at the moment.

Only issues to date are a semi functioning rev-counter (it dies at 2500rpm) so needs some sort of signal boost after the coil pack and the idle stepper motor is a little random for cold starts. I will keep trying settings but I have a Bosch K-tronic idle valve if required.

Bit of wire tidying required and that about it... runs very smoothly and has great torque (feels like it will go anywhere in overdrive top) but it will also rev nicely with a nice surge of torque at 3500+