3.57 stumble and dies at idle

[mpichallenger]

I have gotten my 70 challenger setup with a 3.57 and I am have a bit of trouble trying to get it to tune. Here are the high points

-Its a 97 5.9 block with most of the stock sensors
- Uses a VR sensor in the distributor from an earlier lean burn engine
- Can idle ok for a few minutes, but it will get rough and die eventually
-I cannot get the base idle timing beyond 5 deg. If I do it will run rougher and die. I confirmed with a timing light.
-VE has to be about 60 to keep it idling, lower and the idle will get rougher
-I have a hard time loading the engine at all..I have been playing with VE and timing continually. At each attmept the engine will die, or buck when put into gear.
-I have tries tuning the pots, but they seem to have little effect.
-I thought maybe it was a sheilding issues on the VR wires. The MS is mounted in the driver's comaprtment, so I repalced the dist-to-firewall wires with a twisted pair, but the problem didn't improve.

Any thoughts? Does this sound like a VR wire issue?

[Matt Cramer]

A VR sensor issue will manifest itself as the RPM spiking or dropping out. Could you please post a data log of the problem and a copy of your MSQ?

One other thing - I'd check the distributor phasing. On a 318, I'd set it so the rotor is even with the #1 cylinder terminal when the engine is at 25 to 30 degrees BTDC.

[mpichallenger]

If you set the distributor 25-30 BTC it would essentially be the new trigger offset, correct? So i'd have to go set the trigger wizzard to the same value?

I'll get a datalog and msq tonight. Thanks

[Matt Cramer]

If you set the distributor 25-30 BTC it would essentially be the new trigger offset, correct? So i'd have to go set the trigger wizzard to the same value?

I'll get a datalog and msq tonight. Thanks

Yes, you will need to redo your trigger offset when you set distributor phasing.

[lilsquirt2]

From reading various information on trigger offset and rotor phasing it appears for a dizzy driven signal to work through ms2 the following is required:
Align damper at 25 degrees btdc.
Drop distributor in so the pointer is aiming at #1 on cap.
Set tuner studio:
'tools';
'trigger wizard' 25 degrees btdc
'ignition options';
'spark mode' basic trigger
'trigger angle offset degrees' 60 degrees btdc
Start engine, adjust trigger wizard to match timing light reading on harmonic damper.

If any of this is wrong please correct and explain why.
If this is correct would someone please make the effort to explain in sub-layman terms why this "what appears to be convoluted approach" is necessary?
Also, if all this information is in any one place in a megamanual please show where and if it isn't could it be placed there so those using a distributor to control spark through megasquirt2 will have an easier time. It was only after reading ms3 literature that some of this information came to my attention

[superchargingmachine]

Did you get this running? I am trying to get a similar setup running.

I am trying to follow these 2 examples.
http://www.msextra.com/doc/ms3/distributor.html

http://www.extraefi.co.uk/dizzy.htm