Installed new engine, slight knock under any throttle.
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Installed new engine, slight knock under any throttle. So I got my new engine installed and running off a base tune provided by Mike Norris great guy by the way. So after about the startup putting engine thru heat cycle before dyno I decided to raise the throttle a bit. It stumbled a bit to the air being sucked in And immediately one loud knock so I let off and it idled fine no noises. Do we think this is a tuning issue as it has not had a full tune but will this WED. Just want to make sure all is in check before I put it on dyno and give it hell. I dont have HP tuners so no way to monitor. Just want insight if it is tune related or engine cam timing or something not setup correctly. It has only done it once in about 5 startups with varying RPM. I would think if it is mechanical or valve to piston contact it would do it all the time. Would ease my mind tonight before dyno WED if we all concur its tune related.
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yeh I was standing in front of car by thottle body and when I went to rev it and I mean barely rev the engine it kinda stumbled then when picking itself back up knocked like a rod knock but just one loud knock then stopped. sounded like if you took one knuckle and knocked on a metal door hard. I have yet to even try the throttle again engine and vehicle have not moved yet. Get tune Wed. So maybe I should wait till we can at least monitor this.
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I would like to note I installed a 2 bar map and on the first few initial starts engine ran fine even when revving but smelled real rich. Went to install methanol and signal from 2bar map was not correct found it to be defective today. So I removed intake manifold and installed a new ac delco 2 bar then the problem started happening. I have learned the hard way before and all tools and stuff were accounted for and this noise has only happened once. But it was a loud knock coming from inside. Wonder if the builder spaced the windage tray on this stroker. Still think the noise would be more frequent and weird it just started after the new 2bar that is properly working. So I think the startup tune is off on timing or something. Also when giving any throttle car falls flat on face and almost dies then picks up to rpm fast and picks up.
Last edited by vipvegas; Feb 1, 2010 at 10:32 PM.
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From: Turnin' Wrenches Infractions: 005
Seems to me like a stumble then one knock would indicate possibly a detonation. As it doesnt do this regular like a traditional spun rod bearing or such. Would appear to be a tuning issue to me.
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anyone else have any insight hopefully some that would take my worries away. Oil looks clean at dipstick although I thought for a second when I rubbed the oil between my finger it had a small amount of grit. Could be me been working late and long days on the car. Starting to breakdown and get frustrated.
