Locking a distribtor for use with a MegaSquirt

[daxtojeiro]

Hi,
yeah, as has been said, you set the trigger up to around 45-60deg BTDC, the max advance on a RV8 is around 30 deg, so the trigger (45-60) will come in well before the max advance (30ish)
As has been said, the rotor arm then needs aligning so the edge is aligned with the post at 10deg (minimum advance) and youll easily get to 40-45deg (thats about the max on over run) with it still aligned.
The instructions do show all that I think.

When you get it running simply strobe it and adjust the settings till you get the correct advance, so set the fixed advance to 10BTDC and adjust the trigger angle untill its at 10deg,

Phil

[DaveEFI]

You do have two alignments to achieve- one is making sure the trigger is at the correct angle and the other is ensuring the rotor is where you want it.
I set the engine at 28' btdc - which is what I considered to be the "average" advance - then turned the dizzy around until my rotor was aligned in the centre of the tower. (so 12' would be a bit one way and my max advance would be a bit the other way). http://www.mez.co.uk/dcam/DSCF0330.JPG

Then I made a bracket that replaced the old vacuum advance unit which locked the pickup at my desired trigger location (50' btdc in my application)
http://www.mez.co.uk/ms9.html (all very old an out of date - I run edis now)

Thanks very much, Eliot. Think I'm a bit more confident now on how to approach it. I like to understand things before jumping in and doing it.
Notice you're using an HEI module. I've modified my dizzy to take a hall effect sensor and wondered if there was a better alternative to the MSII power amp? It had occurred the power amp might be better situated close to the coil.

[DaveEFI]

I've got some figures by scanning the cap and rotor then drawing them out on the computer.

Distributor degrees.

Rotor arm contact is 14 degrees wide.

From leading edge of rotor arm just lining up with front edge of contact to trailing edge to back edge of contact, 22 degrees.

So it looks like 44 degrees of ignition control should be possible without any problems.