hesitation

[mysticfalcon]

my 400 has always hesitated a little when i get on the gas from idle. Not just wot but even 1/2 throtle from idle. I gabe moded my mipe and it got a little worse so i tried changing my main but that didnt help. I asked my mechanic and he said i just need to try dif. mains but that didnt help. I thought it would be the needle but he said that the needle should never need to be changed unless u bore. Is he retarded or is it me but if the prob happens at like 1/4 to 1/2 mostly isnt that the needle.

[SGA]

Mine did the same thing when I added a pipe and k&n. Had a bad flat spot if you nailed the gas, 1/4-1/2 throttle. Yours getting worse when you modded the pipe tells the story. You need more gas in the mid range. I moved the needle clip down 1 notch and all hesitation was gone. Your mechanic was wrong as alot of people have to do this with the cylinder bore still stock.

[mysticfalcon]

I like being right espesialy when its over the mechanic