Popping

[hemi400ex]

popping from the exhaust when i go from WOT to letting off the gas abit does that mean its to lean or to rich 2007 hmf slip on (no quitecore) , k&n, lid on, 71, 152 main, 42 pilot, needle on 3rd from top, hills of WV or could have not haveing a quitcore in it be the problem too

[400eXr1d3rZ]

You have near perfect jetting, mess around with your fuel screw, 2 1/4 turns should be a starting point.

[hemi400ex]

it is right now but i lost the damn fuel screw tool i bought so when i get a new one i will thanks

[redexrider]

Fuel screw tool??? you mean a Common screwdriver??

[n811]

the only time I get "popping" is when its really backfiring. Might have a air leak somewhere in the exhaust or intake.

[hornetgod13]

Originally posted by redexrider
Fuel screw tool??? you mean a Common screwdriver??

2005 and Newer 400EXs have a "D" shaped fuel screw.

[400eXr1d3rZ]

Get some tweezers and try turning it, or a tiny pair of pliers, or even get a dremel and grind a straight line through it so you can just both screwdriver and the D shaped fuel screw tool.

[hornetgod13]

DynoJet sells the "D" shaped tool for $3.00. The part number is DT008. You'll have to call them directly to order it.

[hemi400ex]

Originally posted by hornetgod13
DynoJet sells the "D" shaped tool for $3.00. The part number is DT008. You'll have to call them directly to order it.

Thanks should i turn my fuel screw in or out to cut out the popping

[400eXr1d3rZ]

Originally posted by hemi400ex
Thanks should i turn my fuel screw in or out to cut out the popping

I say you should richen it up a bit, so turn it out.

[hornetgod13]

Originally posted by hemi400ex
Thanks should i turn my fuel screw in or out to cut out the popping

"Popping" would indicate a lean condition. Turn the fuel screw out in 1/4 turn increments until it improves.