im not at all offended Lou. I may have more experience or expertise than u at this but it does not mean i can't learn something from u, nor does it mean that my way is best for u. to b offended because ur opinion differs from mine would b kinda self centered and arrogant n thats not my M O. However, i do all my switch flippin and valve tyurnin long before i ever line up to race, and i build my OWN systems, and despite my vast experience and expertise with spray i build them DUMMY PROOF with the best available parts and ALL the nessecary periphial equipment to take full advantage of the system. as a rule i run a 2 stage system, tho i have had and built for other folk systems with as many as 4 stages. I put my 1st or start stage on a throttle switych and set it to engage at WOT, my 2cnd stage is ALWAYS and ADD on rathert than a flip over and i engage that with a hand held AFTER the launch or when the chasis settles, whichever comes 1st, and thats usually on the 2cnd gear shift or jus before same. My preference for spray again is because 1) its only on demand and i can build a relatively MILD engine that is pmp gas friendly with great drivability n fair MPG( mechanical comp ratio n cyl pressure determine ur octane rating needed,if u have an 87 octane compatible engine u can spray the hell out it to the max n still never need to go more than one grade hgher fuel octane rate, in this case it would b to 89 octane). that in parenthesis brings to mind yert another myth that causes some racers to not gain as much power as they could have....too much octane is JUST AS BAD for performance as is too little its jus that ur more likely to incur damage with too little octane. Here is what u must consider, the hgher the octane of the fuel the slower the burn rate because its a dirtier fuel, don't b mislead by the fact that hgher octanes cost more than lower octanes, this is because hgher octane fuels being dirtier incur a greater tax burden which the supplier then passes on to the consumer resulting in the hgher price even tho the lower octane fuels are more expensive to produce, the lower the octane the cleaner the fuel burns, mainly because it burns faster thus burns more completely in the same amount of space n time. with a low octane fuel u can start the fire of combustion a lot later or closer to the pistons TDC, whereas with a slower burn rate u MUST light it closer to BDC in order to insure that it burns completely by the time the combustion cycle is over. Much of the confusion comes with the terms advance and retard timing, when u ADVANCE ur timin ur actually firin the spark plug sooner in the combustion cycle and later when u retard the timin...IE if ur total timin is say 40* that says ur lightin the plug 40* of crankshaft rotation BTDC, ONLY a grunt or TQ monster with relatively low octane fuel is goin to benifit from a timin set that is near or ATDC