my car runs like shit!

fltblkford · Jul 8, 2008

i got a 347 stoker built 24# injectors, upper lower, longtubes,ported stock heads, big cam. it idles fine until it warms up. after that its horrible jumping, backfiring. the builder said "its fine drive like that, dont touch it. it was drove around and it did fine". i got it back home and drove it and it did that. i might need a tune, or is it something else?

xsoutherngun89x · Jul 8, 2008

i would say that with all the mods you have listed there it could use a tune. BUT, for starters check for a vacuum line that may be broken/popped off/cracked.

ScottyDsntKnow · Jul 8, 2008

Honestly your builder sounds like a dipshit. Take it to someone who knows wtf they're doing. Also 24s are too small for that combination.

cdsmith_2002 · Jul 8, 2008

*How about the O2 sensors? Are they new? Even if you don't get a code, they could be trouble. Is the check engine lite on?
*You have long tubes so how is the quaility of the extension cables? Are they manufactured cables or cobbled up with wire nuts or something?
*Do you have a 24# MAF to match the injectors?

Willautoy · Jul 8, 2008

Why would this builder stroke it to a 347 and then use stock heads ported or not?

fltblkford · Jul 9, 2008

new o2 sensors, soldered extensions, 10 codes pop up, stock ported heads 1.90 and 2.02 valves, stiffer valve springs, MAF sensor is calibrated for the injectors. EGR and emissions has been taken off. i got an appointment with fastlane motorsports in benson NC fri for a tune. i changed out my plugs and they were black as hell.