It'll be interesting to see which "slot" my dizzie is on. Should I change slots OR just try going with lighter springs to start..OR both (assuming the slot it's in is lower).
The last DS2 dizzy I had apart that 10 and 15 degree slots. It was on the 15 degree side, and it had the little plastic 'limiter' cap on it... so it probably had about 13 degrees of advance.. the springs weren't too heavy on it (it came out of a Fairmont, '78 or '79... a junkyard dizzy)
IIRC the FSP handbook says not to go over 34 degrees of advance... so if you have 10 degrees of initial timing, and your dizzy is on a 10 degree slot (which is half of crankshaft degrees, so it's 20 on the crank) you will have 30 degrees. Keep this in mind when looking at the slots... not to mention that little clip you have to take off is a real pain to get back in there... and if you do flip it around on the other slot, it's going to
turn your rotor 180 degrees as well... so if you marked your dizzy when you pulled it and put it right back in where it was it will now be 180 off... Hopefully it will already be in a decent slot so you won't have to worry about this.
THe slots just control TOTAL mechanical advance produced right? Whereas the springs control the when, which is my main concern
Yes the slots determine the total, the springs determine when.. although if the springs were stiff enough it may never reach the end of the slot...
There's 2 springs in the stock dizzy, one light and one heavy... the light one lets it advance a little bit a little faster... then it kicks into the heavy one so it doesn't advance too much too quickly (you can feel this by turning the upper shaft while holding the bottom around the gear)...
You can also bend the tabs the the springs are hooking on to adjust the tension they have on the advance... like it says on the web page, it needs to have enough tension to return to the idle position... so don't set them too loose... you'l probably get a good feel for it by messing with it, and using the info on the page...