"Sharp edges" possible issue on intake after 62mm throttle body upgrade causing whistle?

SkylinesSuck said:
Apologies if I sounded gruff at you. My gruff tone was to the bad info.

First off, specific to our PCM, there is no knock sensor and timing is basically set on tables with only sensors like coolant temp, MAP, TPS, RPM, and IAT (I'm probably missing one) telling it where to look on the map. The PCM doesn't look at the O2 sensor for timing, period. What the O2 sensor does get factored in to is fueling in both long and short term trims, and all of this is in closed loop (read not wide open throttle).

The kernel of truth that gets twisted in to bad info is that the fixed maps the PCM looks to for wide open throttle can get moved slightly for lack of a better description by the long term fuel trims. The affect this has on WOT fuelling is small and the power difference is negligible. Now, the PCM can tell in closed loop that something changed and will try and get back to the program fuel ratio to a point (outside of set parameters and you get a CEL) but that only affects closed loop (part throttle) driving conditions.

The PCM has no way to see that you are running richer/leaner at WOT and it's not trying to adjust your new power away to get back to where it was. It doesn't have the ability.
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No apology necessary. I'm not enough of an engine guy to know as much as you seem to, but what it sounds like you're saying is that changing components, (TB size, header, etc), doesn't do much at WOT, which most of us don't see very often anyway, but at LESS than WOT, (closed loop), when the PCM sees something different, the above mentioned TB size, etc, that it tries to adjust the change out of the system to get back to where it's supposed to be. I've heard that since the 80s, when they first started putting PCMs in vehicles. That's where the whole aftermarket"Chip" business started, to reprogram the PCM to take advantage of changes that worked on older engines.
If I'm reading that right, it sounds like we're pretty much saying the same thing. If I'm NOT reading you right, I'd like to learn what you DO mean.
As for the original comment by the OP, I was just trying to help him to not spend money that won't do what he wants.
Please type slow, as I'm not a fast reader.
 
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C.J. Roberts said:
No apology necessary. I'm not enough of an engine guy to know as much as you seem to, but what it sounds like you're saying is that changing components, (TB size, header, etc), doesn't do much at WOT, which most of us don't see very often anyway, but at LESS than WOT, (closed loop), when the PCM sees something different, the above mentioned TB size, etc, that it tries to adjust the change out of the system to get back to where it's supposed to be. I've heard that since the 80s, when they first started putting PCMs in vehicles. That's where the whole aftermarket"Chip" business started, to reprogram the PCM to take advantage of changes that worked on older engines.
If I'm reading that right, it sounds like we're pretty much saying the same thing. If I'm NOT reading you right, I'd like to learn what you DO mean.
As for the original comment by the OP, I was just trying to help him to not spend money that won't do what he wants.
Please type slow, as I'm not a fast reader.
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I think we are still saying different things. I'll try and get back to it tonight, but work is being a pain in the ass so it might be tomorrow. Short answer though is bolt on mods make more power at higher rpm and WOT. This power is also pretty limited on our low revving, low ho 4.0s and mostly useless for most Jeep guys who don't find that power useful. That's where I completely agree with the standard line most people give on here about bolt ons not being worth it.
 
Head Lice said:
January 21st.
Ladysmith, BC
87 octane gasoline.
$1.749 / litre
$6.621 / US gallon

Why modify and create
the need to run a higher
octane/priced fuel?
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Are you asking others to answer that for you? Or are you expecting individuals to justify their reasoning to you?

Also, gas prices aren't $6.62 for everyone. It's half that in AZ.
 
C.J. Roberts said:
No apology necessary. I'm not enough of an engine guy to know as much as you seem to, but what it sounds like you're saying is that changing components, (TB size, header, etc), doesn't do much at WOT, which most of us don't see very often anyway, but at LESS than WOT, (closed loop), when the PCM sees something different, the above mentioned TB size, etc, that it tries to adjust the change out of the system to get back to where it's supposed to be. I've heard that since the 80s, when they first started putting PCMs in vehicles. That's where the whole aftermarket"Chip" business started, to reprogram the PCM to take advantage of changes that worked on older engines.
If I'm reading that right, it sounds like we're pretty much saying the same thing. If I'm NOT reading you right, I'd like to learn what you DO mean.
As for the original comment by the OP, I was just trying to help him to not spend money that won't do what he wants.
Please type slow, as I'm not a fast reader.
Click to expand...

One other quicky note--I don't want to confuse bolt on mods making or not making power on a 4.0 vs the PCM supposedly "adjusting" things to negate power mods you have added. Two separate things, and I'm saying the PCM doesn't do that (to a meaningful degree). A custom tune certainly helps maximize gains though. More tomorrow.......
 
Mikee024 said:
Are you asking others to answer that for you? Or are you expecting individuals to justify their reasoning to you?

Also, gas prices aren't $6.62 for everyone. It's half that in AZ.
Click to expand...

I expect no answers.
The $6.62 is the amount that we would pay for the equivalent US gallon here in Ladysmith, BC.
Sorry if you were unable to grasp that concept.
 
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Head Lice said:
I expect no answers.
Click to expand...

Then why did you ask the question? (see above lol)

Potential answer: You "expect no answers" to your question because it was rhetorical and intended to assert your stance on others. (ding ding)

Head Lice said:
The $6.62 is the amount that we would pay for the equivalent US gallon here in Ladysmith, BC.
Sorry if you were unable to grasp that concept.
Click to expand...

Analysis: You cherry-picked from the first part of your post then doubled down by speaking down to me.

Summary: At best, your two posts provided no value to the conversation. More likely, your posts resulted in a negative net value to this thread.

Suggestion: Become an energy/life consultant to influence life policies per your opinions and local gas prices.
 
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Mikee024 said:
Analysis: You cherry-picked from the first part of your post then doubled down by speaking down to me.

Summary: At best, your two posts provided no value to the conversation. More likely, your posts resulted in a negative net value to this thread.

Suggestion: Become an energy/life consultant to influence life policies per your opinions and local gas prices.
Click to expand...
Not much to do in New York? 🌈
 
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aidanm said:
A new one
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I would get a different BBK 62mm if that's what you want to run. The one I bought (and returned) didn't whistle a peep...and my stocker did/does.

TJ Jim said:
So you probably have two leaks. One vacuum and your new throttle body.
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Both are likely vacuum leaks. My bet is on it being from either side of the TB shaft.

My stock TB whistled and the only locations leaking during the boost test came from each side of the shaft. I tried a 62mm BBK to see if the boost leak would go away, but the BBK's leak on either side was worse than my OEM. With that said, it solved the whistle lol. I returned the part because it didn't solve my problem.

Best of luck OP.
 
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