Finished 5.9 swap questions
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Ok so of course I bought a Hughes plenum plate when the 360 donor was overhauled. My guess exactly that the 318 pcm wasent giving enough fuel under heavy acceleration. I really don't think I'll go to obdII. The 94-95 mopar 5.9 pcm will work but will octane boost every fill up hurt? We have 90 as premium here. Also what about having b&g flash for a mild 360. And the backfire is actually 45-55 and feels like the header meets the y pipe area. Maybe my exhaust has too much back pressure or too little? Thanks for the replies!
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I lost that mopar pcm more than a year ago. I'm running my oem pcm. it somehow disappeared between addresses. I'll remove that from my sig soon enough. Good spot. My previous comments I believe stated factory. Currently I'm running 90 just because it's running smoother at this moment. Still stock 318 pcm with a cammed 360 and full bolt ons. I could put a couple pics of the finished product but don't really have any "in the process" pics.
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I will look into the mopar pcm for a 5.9L. I was just worried about octane boost with mmt every fill up for years to come as a detriment to my engine. Nobody has told me otherwise so Im guessing its fine.
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Good to know. I've ordered a mopar perf pcm for the 5.9. I'm assuming the harnesses fit just the same for 94-95 auto. I reset my pcm by removing the negative cable and it runs a bit better so the 5.2 pcm is simply trying but cannot supply the necessary fuel. Also I think my fuel pump is running 38-39 psi. I believe that's below the min threshold. Something I might need to look into. Thanks for the input. I've also got to realize I have only 800 miles on the fresh 360 so it's still breaking in.
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How do you really know if your running lean or rich without a wideband or dyno run. Speculation at this point. I agree with snowbound mp pcm set sync. Sync set to far negative will cause backfire stumble host of other issues b/c injector is fired to soon. Adv sync causes no ill affect other then not starting if to far adv but so will retarding the sync. Can go to a larger injector but doubt it needs it. Oem are 24.5 at 39psi.
Last edited by tweeker909; Mar 26, 2015 at 05:10 PM.
