ok my 460 stumbles after 4000rpms im thinkin it might be the fuel pump because it runs fine till that point and can run good past 4k if im not racing it, it has a inline fuel pump but it doesnt have a name or number on it on a psi rating and i have a holley regulater. does this sound like the pump is not rated at a high enough gph? the motor has kb hyper pistons 10:1,ported and polished stock heads and weind stealth intake, 750 holley and headers 2 1/2 pipes no mufflers. so im thinking it might be this off name brand pump and was lookin at a holley hp 125 fuel pump. and it has new plugs but not wires and i went out tonight and started the motor and i could see the spark through the plug boots on all 8 and 1 at the dizzy should i be able to see that or should i replace them?

 

why get that big ol pump?? you only need 8-9 psi for a carb...its possible that pump isnt located properly, some pumps are pusher pumps and need to be by the tank, some are puller pumps and should be further forward...i would get a decent pusher pump and mount it up under by the tank....if its not the pump, you might need to find a chassis dyno somewhere and try tuning the carb with different jets.....but first off, try new plugs...we had a customer come to our shop for a chassis dyno tune, his big block bowtie would run great till 4500 rpms then fall on its face everytime...he tried jet sizes from 85 to 100 something with no change...he swore up and down his plugs were new, 4 hours of dyno tuning later (at $175 hour) he decided to listen to us and try some new plugs, and whalah!! his motor ran just fine through the whole rpm range...moral of this story, MAKE SURE YOUR PLUGS ARE GOOD!! They dont have to look be to be bad....

EDIT: sorry i just reread the last part of your post....ABSOLUTELY NOT!! you should not be able to see spark whatsoever!!! theat is definitely A problem if its not THE problem...replace those wires and get back to us....

 

If you see any arcing you need new wire NOW. on the pump and refulator, 8 or 9 psi is way to high for a carb. 7.5 is a much better number and will cause less problems. You need to check the flow rating of the regulator as some of them won't let the required volume thru. However your problem is your plug wires.

 

thank you sir, and i understand what you mean by the plugs and i will change them with the wires but i only said they are new because i changed them about 2 months ago but when i think about it thats now really that new is it. o and it sits at 7psi at idle and the pump is mounted on the frame under the tank so it mounted right.
lol yeh you can see at every boot other then 7 on the dizzy the spark though the plug boots and one at the dizzy looked like it was trying to arc over to the cap clamp. i will post back and let you know if the plugs/ wires fix it.

 

I doubt that 2 month old plug are part of the problem. When you stress an ignition system with extra fuel when under hard acceleration or WOT it takes extra voltage to fire the plug. If the voltage has a path to ground ( the arcing you see) other than through the plug, then the plug does not fire. Just change the plug wires with a quality set of wires.

 

Yes you have a bad wire, but it might not be your only problem. 13 to 1 comp motors are built, and with good wires they dont have a voltage leak, so your 460 shouldnt. Ive had top of the line MSd's that put out enough poer to arc weld not leak. Anyway, FYI i always use accel 300+ race wires, and only these, the rest of the wires they make are junk. Ive done many care and trucks up with other brands and spent more, but I always seem to have better luck with the 300+. My last set had ben on 3 diff. trucks with very hot boxes on them, still no leakage!