[allistairc123]

hi guys, first of all, i wanna say, my raptor is my life and if i can cet any help would be so greatfull.

i have a 686 with 12-1 piston, i was wondering does anyone have suggestions for ignition timing changes to maximise performance.
i have a dynatek programable ignition, so i can input anything.
i was advised no more than 34 to 36 max advance.
thanks u guys

 

[CoalShedRacing]

program 2 curves for it, one with 35 degrees total and one with 32 degrees total and see which one you like the best.

 

[rt]

are you advancing the timing or retarding the timing?

 

[CoalShedRacing]

stock is 38 degrees total so you're retarding the timing.

 

[rt]

gotcha, I seen he wrote "advance" and it threw me off :crazy:

 

[allistairc123]

i was wondering was there anybody running simmilar setup? what sort of power i should be making?
the facalities are very very limited on this little island so any minor upgrade is a 'big thing".
i have no idea what sort of curve to use, but i have tuned it as best i can, it is responsive to the stab of the throttle, pulls well right through and revs near right out, but it spits blue flame with gentle 3rd revs blips - why????
is there a rule of thumb for compression increase-timing change?
thanks

 

[Mad Dog]

I haven't seen much in the way of hp increases from timing changes on the 660 motor, except for some high altitude applications that I haven't seen duplicated.

Even when comparing the pre-programmed curves on the Dyna there's not a statistically significant increase from stock.

I'm just curious, what elevation are you at and what fuel are you using?

 

[allistairc123]

thanks mad dog, i think im about 600ft just and i usually run pump gas which i think is either 95 or 97 - risky i know with a 12 to 1, i usually add octane booster though.
when im going to thrash it i would run av-gas. thanks

 

[allistairc123]

i ment to say, ive seen claims of 6 horse with the dynatec ignition- think it was outta controll racing, he was running a 686 and other simmilar set up to me

 

[CoalShedRacing]

i ment to say, ive seen claims of 6 horse with the dynatec ignition- think it was outta controll racing, he was running a 686 and other simmilar set up to me

If you look further down in the "660 modifications" home page you'll see something I posted called "dyno testing results" you can see all the pre-programmed dyna curves and how they performed vs the stock curve.

The 2 retarded curves I told you to program did not show a large power increase but the motor did rev quicker.

 

[allistairc123]

cheers coalshed, i will have a wee look

 

[rt]

theres also a topic about using octane booster....more or less a waste of money!