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Discussion Starter · #1 ·
I figure there is still oil/gas in my intake manifold. So how long will it take for it to make a difference in the amount of knock retard i am getting? I am getting 2-3 degrees of short term knock with the canned 91 diablo tune and crappy CA 91 oct gas. I can say there is not an immediate difference.
 

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I would not expect to see any immediate change from installing the catch can, maybe no long term difference except less oil in the intake. 2-3 degrees of intermittent ST KNK is not much at all. I had to mix gas to 95 octane to get rid of the intermittent 4-5 degrees on my 09 SRT with the factory tune.

Maybe you should try a custom tune.
 

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Discussion Starter · #3 ·
I would not expect to see any immediate change from installing the catch can, maybe no long term difference except less oil in the intake. 2-3 degrees of intermittent ST KNK is not much at all. I had to mix gas to 95 octane to get rid of the intermittent 4-5 degrees on my 09 SRT with the factory tune.

Maybe you should try a custom tune.
That doesn't sound very promising. :/
 

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If your ST KNKs are being caused by oil residue, it may take a while before all the pooled oil is consumed. Personally I would clean the intake but that is only after I have exhausted other more likely suspects.
Log some pulls and see where the ST KNKs are happening then try to add a little fuel in the range you are getting them or pull a degree in that range and see if they stop. If you don’t want to mess with the tune, add some octane booster to some fresh 91 octane and do some logs to see if they are reduced.
What is the engine load when you’re getting them? If you are in a higher gear and load it (almost bog it), it is more likely to register a ST KNK than if you are wound up at a higher RPM.
Are you at WOT or partial throttle when you get the KNKs? Pulling timing or adding fuel will only effect WOT so if your getting partial throttle KNK, you'll have to go back to your stock tune and modify it (remove MDS, increase throttle boost, reduce fan setting if you have a 180 stat, maybe add a degree or a little fuel, etc.)
If it is real hot where you are, a 180 stat and lower fan settings will really help reducing ST KNKs. Cooler engines are a lot less likely to knk.
Occasional ST KNK at shift can be normal (or next to impossible to remove without a custom tune to pull more at shift) but ST KNKs under WOT after a shift is not good. Every degree of timing pulled is worth between 3 and 4 HP up to MTB (max Tq).
 

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Discussion Starter · #5 ·
The knock is mostly WOT just before the shift. I will try adding some fuel up top. I haven't really messed to much with the trinity. I think headera and a custom tune is next. Thanks for the input.
 

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I was getting KNK readings because my K&N CAI bracket was rattling.

Make sure everything is tight in and around your engine.
 

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The knock is mostly WOT just before the shift. I will try adding some fuel up top. I haven't really messed to much with the trinity. I think headera and a custom tune is next. Thanks for the input.
5% up top may be the ticket or you could always pull a degree up top. That will tell you if it is real KNK or false from a rattling exhaust or drive line component. If it were me, I would pull a degree up top to ensure it goes away and then put it back and add the 5% fuel and see.
Headers, even the 392 shortys, and tune for it is a winning combo with the 5.7s...
 

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Discussion Starter · #8 ·
It has gotten worse. I made sure everything is nice and snug, but got up to 5 degrees. I used the NOS octane booster before i had the CC and i was down to .5 at most. I think i am going to run some more and see if things settle down.
 

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classic signs of crap gas... Too bad. I'm in the same boat, that's why I'm running a Snow water/meth fogger. Cheaper than race fuel or fuel additives and gives me more octane and lowers the intake temps too.
Are you running a 180 stat? You stated it is worse, has the weather been hotter in your area? Heat really makes these hemis detonate...
 

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Discussion Starter · #10 ·
It hasn't been hotter. If anything it has been cooler the past few weeks here. I haven't done the 180 thermostat yet. That may be next.
 

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It took me less than an hour to install a 180* stat and clean the inside of the intake manifold. Did mine when I swapped TB's. I was 74 years old at the time , Will soon be 77, have diabetes, heart problems and am assortment of other ailments.FWIW had zero oil on the backside of my throttle plate and a minimal amount of oil in the intake.
 
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