zittman

iTrader: (4)

My truck is pinging under boost from 4k on up. I am running a walbro 255 intank pump. I have a Vortech V2 supercharger with a 2.87 pulley. Running 13lbs of boost. I have 75lb injectors, 90 mm throttle body, FLH, Tuned by Blackbear performance. Do I need a different pump?

dirt track racer 81

iTrader: (45)

sounds like its either got too much timing or the a/f is too lean? is this a mail order?

WJ MARK

iTrader: (7)

you running any meth with it??? sure helps with the higher boost and timing.

Sleeper04

iTrader: (6)

Ya, you could be out of fuel. Walbros are normally only good up to the 500rwhp mark unless you are using meth to compensate. I would check the fuel pressure and see if it falls off at the upper rpms. If so, start looking for another Walbro for a dual setup.

SILVERADO11

Either the tune has too much timing or not enough fuel, also as stated above you could be running out of the supply of fuel meaning check to see if your fuel presure drops much. i had a pinging problem and i got a dyno-tune and cleared it all up she was running alittle lean and we pulled some timing. she runs great know, but the real test will be this summer in 115 degree dry heat of arizona. good luck!

trever1t

iTrader: (14)

Whatever you do don't keep going into boost and seeing if it is 'fixed' Get it checked out.

scooter k

iTrader: (22)

I pick up about 2 degrees of KR at 5500. I can't hear it but see it on Hpt.
I'm also running 13psi and finding out 91 pump gas cannot support that much boost. I have a meth kit that I'm installing. My fuel pressure drops off at higher rpms but afr hangs in there at 11.8.

sharpshooter

iTrader: (10)

Do you have a wideband and what motor & cam?I can't remember what your set-up was.I doubt Justin has a lot of timing in it.My 255 could not keep up with my 6.0 & cam at all.

Dumb ? You are running a new tank of 93 octane?

joeyc125

iTrader: (7)

How much FP are you guys dropping in the high end? I hear its normal to lose a little, but how much is too much?

scooter k

iTrader: (22)

Mine normally runs 55psi and ramps to 88psi but as I approach max boost drops to 40psi. It is normal to have it drop but don't know how much is normal. I have a FPCM so I can mess with my fuel pressure.