[Guest]

The stock Microplex ignition a

The stock Microplex ignition advance at WOT is about 32.5 @ 5K. I know the 2v motors carry a bit more, especially the early carb's cars.
The Forza Carobu article says that adding advance to the 308 engine (38 degrees) helps power output.

Would be interested in folk's experience with the effect of adding more advance, and if any precautions apply to a 4 valve engine.

Many thanks
Russ

 

[Guest]

Hi Russ,

ignition timing be

Hi Russ,

ignition timing began to vary for emmisions reasons rather than power output. the more retarded the spark (in relation), the higher the combustion temp, the better the burn off of oxides of nitrogen (NOX).

I'm a firm believer in advance across the curve, and my personal maximum preference is 36 degrees. The one caveat is the avoidance of detonation at all costs as it can break rings, hole pistons and even destroy rod bearings.

Although I'm old school and have never seen one, I'm sure there must be a mathematical formula/equation to work out a graph to maximize the advantages as crank/piston speed increases that also takes stroke into account.

Regards, JRV

 

[Guest]

Jrv
thanks for the reply!
Wh

Jrv
thanks for the reply!
When you say advance across the curve, do you mean full advance in across the curve or advance progressing throughout the curve?

thanks
rt
OBTW, based on the rapidity and quality of your reply, my daughter says 'JRV rocks!'

 

[Guest]

I was trolling both sites befo

I was trolling both sites before calling it a day...

No not full advance across the curve, maximum safe progressive advance for piston speed.

Several guys here play with this stuff, perhaps they know of a formula to help calculate the progression curve?