Vantastic

[BPVan]

I drove it to Crown Hill and back last week before our meeting and I noticed the MSD was a little warm, nothing alarming. I am going to get a 12v whisper fan from DigiKey and create a small air flow through the box to keep it cool.

I have been also playing with the timing after talking to Pat at the last meeting. The issue I am having is the vacuum advance is causing some back fires which tells me it is advancing too far on acceleration. I observed the vacuum advance lever with it connected and noticed it pulled the most on the initial throttle then varied as I applied more throttle. I have been leaving it off for now but under heavy acceleration (hills) there is some knocking and lack of HP of course.

I pulled the duraspark apart tonight to adjust the mechanical advance and noticed I had it set on 24 instead of 16 (plus the 10 degrees at idle). Murphy's law set in and one of the advance springs (the lighter one) took flight somewhere so I am going to get the Mr. Gasket 925D kit as recommended by http://classicinlines.com/DSII_swap2.asp. I also understand now how to limit the advance by adding some weld to the mechanical plate to close the gap. I am going to start with the 16 and see how it goes from there. There are also many adjustments on the Holley I need to play with.

It seems like it could take me a month or more to really tune this engine in to the "sweet spot". Overall it has been firing right up and burns real clean, the electric choke is working well and the MSD 6AL with the Blaster 2 coil is real smooth. More to come, I'll take a video of my first wheel stand

[falcon cobra]

Hey there, the vacume advance doesn't work on acceleration,because the vacume is low close to zero, and the number on the advance plate is x 2 so one that says 16 its 32 + 8 or 10 will equal 40 or 42 , I have mine on the 12 degree side so 24 + 12 is 36... hope this is helpfull john h

[Luva65wagon]

Hey there, the vacume advance doesn't work on acceleration,because the vacume is low close to zero

Is this true? I think it is true if you are talking intake port vacuum (below the carb base), but I think the carb makes throttle-related vacuum based upon venturi air speed at the port you hook up to the vacuum advance. That is throttle-related vacuum. Yes/No?

[falcon cobra]

I guess it would be, with that port which is just above the blades no vac. at idle when they open more than about 1/8 or 1/4 the vac. is the same as it is below the blades. with the pedal mashed in the rug 0 vac. thats when boost comes in handy ....john h

[pbrown]

Here is a good article on Duraspark tuning.

http://www.carbdford.com/viewtopic.php?t=5543