Timing

[buguy]

Idling will raise the temperature by a quite a bit.......I saw a high of 330 degrees idling in the armpit of America....Barstow, Ca. when my buggy started pinging at cruise due to 106 degree ambient temps and intake temps of close to 130 degrees at cruise.
Lately I was seeing 250 degree cruise temps but have gotten that lowered to 210 degrees with a completely new ignition map below 100 kpa.
It's not easy finding out what your engine likes the best. They will run on almost anything but getting optimal timing takes some work.
The problem is that every engine is different too.....

What I did is take a graph of all the VW distributors and plot them on an ignition map in TS. I then ran a couple of them and tweaked them to get the best vacuum at cruise to optimize the ignition....you can feel it in the pedal when your engine likes the advance.
I like how it's running but my fuel mileage is not very good for some reason.......but the throttle pedal feel has improved by a significant amount....that and my EGT's are down and my CHT's are lower at cruise.
I have my cruise set at 15.1:1 AFR right now. I don't usually go much leaner than that due to pedal feel.

Thanks Art. This being pretty much all new i don't have much of a baseline to start with. Also running E85 i don't have much to compare it to. Right now i think I'm at around 15 degrees at idle and Max out at 38 degrees cruise. I too get somewhere near 15:1 afr at cruise. 13.5 or so at idle. My truck showed 109 degrees out when i got in it. Settled down to 99 after some driving. So it was real hot out. Mid 80's is average right now, so hopefully it cools down a bit. I see 120 or so IAT at the moment.

[Clonebug]

With the E85 you can run higher timing ..or so they say....But you are also running about 30% more fuel than with E10.

I was running 15 degrees at idle but I found the ramp up to 32 degrees at 3000 rpm was too fast and at light cruise in second or third gear I would get some surging.
There is a graph on the internet with all the VW distributors plotted with their mechanical advance vs rpm. You have to add the initial advance you run to that amount but it does give a starting point to them.
Non of them are a straight line and they all peak at different max advances at different rpm's.

Here is the mechanical graph I used.......I just use a straight edge and plot the rpm points on my map to coincide with the mechanical advance numbers....then add the initial I use to that number.

https://www.bing.com/images/search?view ... ajaxserp=0

I just now found another graph plotting the vacuum advance so here that is.....

https://www.bing.com/images/search?view ... ajaxserp=0

[buguy]

Interesting. I will have to see how mine compares.