Lean past half throttle????

[300EXrider356]

Allright, well I just reuilt my engine, and Ive been messing with my edelbrock. Now I have the jetting right on the bottom end, but the when I accelerate past halfthrottle, it will kinda pop, I think because its just not getting enough fuel. Is this lean?

thanks
Mike

[vze2hnvz]

Popping on accel. or when you let off?

[300EXrider356]

Accel, I think its being starved for fuel. Since the needle thats in it is the same one I had before and i got P&P and a 12.5 to one wiseco piston. I think its a 25E, Im gonna try and get a 26E.

Mike


Also, I dont think its detonation, because im running 50/50 of 110 and 92. What are some signs of detonation.

[vze2hnvz]

Sounds a bit lean to me....

Results of pre-ignition:
spark plug tips can be broken, or melted, and other internal engine components such as the pistons or connecting rods themselves can be damaged

Porcelain = the porcelain shows up preignition/detonation, it will not accurately reveal jetting/air/fuel ratios. To look for the beginning signs of detonation, search the white porcelain for tiny black specks or shiny specks of aluminum that have fused to the porcelain. When detonation occurs, part of the air/fuel mixture explodes instead of burning, the explosion is heard as a "metallic knock", this audible knock is the result of a sound shock-wave, this shock wave travels back and forth across the clearance volume "disrupting" the cooler boundary layer gases that cover the entire clearance volume area. This disruption allows "more" heat to be transferred into parts, especially, domes/piston tops,...along with the very rapid rise in pressure like a hammer blow, pistons can get torched with melted sides and holes. With the early signs of detonation, the shock-wave will also rattle rings causing the tiny amounts of oil that now gets by rings, to be fused to the white porcelain as tiny black specks, also fused as specks are soot that was clinging to clearance volume surfaces in the relatively "still-air" of the boundary layer. One step beyond the black specks, will be tiny specks/balls of aluminum coming off the pistons that will be fused to white porcelain,....the next step to be reached is occasional pieces of the porcelain being broken-off as detonation gets worse, ETC. Soon after that are holes, blown head gaskets, broken connecting rods, ETC.

Additional signs of beginning detonation are piston rings. By comparing ring's "free-diameter" to "out-of-box" free-diameters of new unused rings will reveals beginnings of detonation before much harm is caused. This is a result of the above previous explanation about heat being transferred more readily because the of the relatively insulating/cooler boundary layer being disrupted by the shock-wave. A piston ring is a simple spring, when a spring is overheated it will loose tension.
Center Electrode = the very tiny sharply defined porcelain -"ditch" that encircles the center electrode, will also show up early signs of preignition/detonation and the wrong heat-range. Look for signs of the ditch beginning to be filled up with melted porcelain, you will need a 5x or 10x magnifying glass.

[firefighterjosh]

My friend always had problems with his edelbrock

I say throw it aways and buy a 450 carb.

[300EXrider356]

allright well I looked at my plug and it had like 2 black specs on it, thanks for saving my engine dude hahhaha. Im gonna bump up the mixture to like 3/4 race gas and a fourth premium. Thanks a mill
Mike