Bosch 3.0 curve chart
 

Anyone know where I can find a gen-u-wine Bosch distributor curve chart for the 3.0L engine? Have a good idea what it should be but someone wants the real deal. any year will work.

James,

You'll find that in the Porsche factory shop manuals. They are different for US & ROW as well by year.

Thanks steve. I'll pass that on.

I have the factory shop manuals and found the distributor curves in section 9. See below.

I scanned the distributor advance curves for the 80 and 81 SC. The factory procedure for setting the timing is the same. -5 BTDC at 950 RPM with both vacuum lines connected. Given today's gas, I back this off to -3 BTDC.

As you can see, the high rpm slope in the advance curve is at about 3000 rpm SHAFT SPEED which is 6000 engine RPM (Distributor turns at 1/2 engine speed).

http://www.petry.org/pics/80SCDizzy.jpg

http://www.petry.org/pics/81SCDizzy.jpg