backfire through the carbs ..., makes for nice fireworks! |
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backfire through the carbs ..., makes for nice fireworks! |
SirAndy |
Jan 30 2005, 01:18 AM
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#1
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Resident German Group: Admin Posts: 41,675 Joined: 21-January 03 From: Oakland, Kalifornia Member No.: 179 Region Association: Northern California |
hey, it's me again, the "carb-hater" !!! (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)
i've been trying to get this engine to run right for what now, 10 months??? (IMG:http://www.914world.com/bbs2/html/emoticons/headbang.gif) i still have a issue with backfires upwards through the carbs (looks cool at night with the GT-engine lid) !!! now here's my question: - i'm still running stock (well, SSI) heat-exchangers and a close to stock (Manta) exhaust. - i have a cam with a lot of overlap. could the stock(ish) exhaust setup cause too much backpressure and the engine doesn't flow and belches back through the carbs ???? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) Andy PS: this happens all over the rpm range, but more often under lower rpm load and higher rpm "cruise" (steady gas) and only sporadically at WOT ... |
redshift |
Jan 30 2005, 07:53 PM
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#2
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Bless the Hell out of you! Group: Members Posts: 10,926 Joined: 29-June 03 Member No.: 869 |
It just sounds like late/early spark to me... and maybe weak in some ranges. (Also see above ref: Tailight grounds for the weakness... sounds like a winner..)
Seems like the curve on the distro would also cause something akin to that, so I defer to Jake E. Ngine. But, I do think it'd be funny to try to help Andy get his engine back together, in threads full of UFO/Martian/Fiscally Responsible Polititian/Yeti pics.. and masked broken English profanity.. (IMG:http://www.914world.com/bbs2/html/emoticons/laugh.gif) Skippy Skipperton |
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