Friday, June 26, 2009

Pyrometer install and a birthday visitor

Sue's friend Jeannie stopped by with a birthday gift for Sue.
Drilled and tapped the right manifold to put in a thermocouple.

Exhaust temperature is a cross check for O2.

Saturday, June 20, 2009

"G" cylinder heads and valve cover baffle differences

Grabbed a set of G heads off a 1971 Toronado for spares. These had valve rotators. The intake stems were dry so the guides are not completely shot. The valves have a good margin and are not recessed so there is some life left.
The bottom clean cover is what came on my 1975 455 and it has a short baffle. The top dirty cover has the long baffle and was on the 71 Toro. Wonder what year they changed?

Sunday, June 14, 2009

VR sensors

Ford variable reluctor sensors. I read that the tooth width should be the same as the armature diameter of the sensor which this wheel matches. If the tooth is wider the zero crossing point will vary. I ground off the end of one sensor to see what the diameter really was. As far as the tooth form goes I read that they should be like an involute gear but I have seen square and rounded bottom forms like I made. After market wheels and OEM wheels are made with all forms of teeth. The square top edge can tend to make the sensor "ring". Also the tooth gap should equal the tooth width which couldn't be done with this diameter of wheel and sensor. Time will tell but it should be OK. Of the two styles of sensors here all have about 650 ohms resistance.

Saturday, June 13, 2009

Crankshaft position sensor modification

I'm going to experiment with a crankshaft position sensor. Megasquirt can use this for a tach input. This is a 36 minus 1 tooth wheel. Used a 36 tooth cam sprocket for indexing in this fixture. The plan is to mount this wheel on the harmonic balancer.
Trigger wheel is .312 thick and that is more like what Ford used in their EDIS system. Most of the aftermarket wheels are .125 thick. I wanted a thicker wheel so it wouldn't be so sensitive to axial position. This is a step towards sequential injection, still need a cam position sensor for that. Right now the tach signal is coming from a 7 pin HEI distributor and it works fine. The easiest place to put a cam position sensor is where the distributor is now. This wheel will allow a distributorless ignition like Fords EDIS to be installed freeing up the distributor for modification.

Monday, June 8, 2009

AC compressor mount gap

Emily Philbin turns 16 and Sue made up this flag we put up so it could be seen from the highway.
Bob Drewes clued me in to the gap that needs to be taken up with a washer on the rear AC compressor mount. The compressor is a Delco reman that is kind of a universal fit all. It can be used with a superheat switch or not and comes with a plug for the switch. I watched the original as it was unbolted and don't remember a gap like this. Gap was about .075". Maybe the difference is in the rear head of the compressor.

Sue got a personal fan. I programmed to display Megasquirt 2 version 3.

Monday, June 1, 2009

VE tables and 700 miles of Automatic Mixture Control

We got to attend the Greater Midwest Classics rally held at Waseca MN. A great group of GMCer's. 28 coaches showed.
Stopped on the way to the rally to return some GMC books to Larry C. He was nice enough to loan them to me last year. We hope he gets his coach going soon.

3D map of present VE table. Click on images to expand.
Present VE table
VE table before 700 miles of Automatic mixture control. Most of its tune was between 45 and 85 mpa and 2200 - 2800 RPM. Some of the changes were manually put in.

Cold start is not great yet, trying more open idle step settings, less afterstart enrichment and more warmup enrichment. Only one thing at a time with this action plan.

Hitting knock retard occasionally.