backfire through carb at wide open throttle
#1
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Car: 1986 trans am
Engine: 355 sbc
Transmission: th 350
backfire through carb at wide open throttle
i have a stock sbc im fighting. stock internals with highrise intake, edelbrock 600 carb and headers, ran good for 6 months now at wot i get very bad backfire through carb did complete tune up , nothing changed, checked timing , nothing, swaped disi. nothing, installed vacum gauge to check for bad cam vacum gauge steady , cams good im guessing. swaped fuel pump no change cleaned out carb no change. when you hit 4,000 rpms if falls flat on its face all mos like its not getting spark let off engine comes right back. im lost any ideas . all greatly appreciated thanks
#2
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Location: Wilmington, Massachusetts
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Car: 1983 Z28/2000 ZR2
Engine: CFI to carbed 305/ 4.3
Transmission: Built 700r4/4L60e
Axle/Gears: 3:23/3:73
Re: backfire through carb at wide open throttle
I would verify that fuel isn't cutting out at wot, install a fuel pressure gauge that you can tape to the windshield, for instance. Are you running a mechanical or electric pump?
#3
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Car: 1986 trans am
Engine: 355 sbc
Transmission: th 350
Re: backfire through carb at wide open throttle
mechanical pump have good pressure i think it has to be valve float any body with any ideas
#4
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: backfire through carb at wide open throttle
Spark plug wires bad? Lean pop maybe? Choke door closing? Carb tight to intake with no vac leaks? Intake bolts tight?
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