Just Fishing's 09 Tahoe Build thread

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Just Fishing

Just Fishing

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Well i decided to go back through my tune and make some adjustments to the transmisison.
So i started editing the one i thought i had flashed the hoe with, and found it has the trailblazer SS timing map

so i decided to just pull a fresh one from the hoe.
sure enough, trailblazer ss timing.
:yaoface2:

I don't know what/where the fk i did with the timing...

so i proceed to make two new files.
One with the 6.2 timing
and one with the 6.0 HD timing.


So just for general reference.

6.0 trailblazer SS High Octane timing.

1625883070945.png


6.0 2500 HD timing.
1625883119801.png

6.2 escalade timing
1625883178057.png
This is just a general overview, other tables add and remove from the table.

So i loaded up the HD timing first.
Runs a little better, More top end!
No real pinging notices in the log, maybe 1 degree.
I like it better than the SS timing, engine seems smoother.

So then i decide, wth lets load up the 6.2 timing

Oh baby!!!
Me likey! :boobs:
More power everywhere.
the hoe is happy.

logging, i'm seeing just a few degrees of timing retard due to knock sensor input.
Not a huge amount, but enough that i put it back to the 2500HD timing for now.

I'll play with it later, after engine break-in, and with a full take of premium.
 
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Just Fishing

Just Fishing

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Last night i did some thinking about some valvetrain noise i hear under light load at around 3200-4000 rpm.
It's been bugging me a bit since it seems to be getting louder.

Maybe i need longer push rods, lifter is being difficult/faulty, or maybe I need to ensure i fully torqued them down all the way.

The sound reminds me of my old S10, if you get the throttle cable routed incorrectly, it can pulsate some engine noise right down the cable into the passenger compartment.
but there are no cables that could do that in the tahoe...

Other option is the hard line i used for the catch can.
but i have that setup with rubber flex joints, and lined with the same stuff anywhere it makes contact with anything hard.
Mostly to prevent wear, but it should also sound deaden.

Then i remembered something, the 1.8 rockers.
I did some reliving of the valve cover to prevent this issue.
It's possible that in this area of rpm, i have enough oil pressure that the rockers are moving up more and hitting the valve cover.

I did some driving around last night to repro the sound, and with the windows down.
It's louder outside the truck than i thought, but it's still hard to hear unless i'm driving against a wall or another car.

If they are even slightly coming up and hitting the valve cover, then there is my issue.

So my task later today, pull the valve cover on the driver side.
if I see signs of contact, more reliving.
and I'll probably do the same to the passenger side if it's found.

from there, I'll probably bite the bullet and order some spacers and the updated valve cover.

I'm crossing my fingers that this is the issue, but i doubt I'm that lucky. :hahano:

:violin2:
 
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08z71bgm

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Don’t pull timing if you have KR add more fuel via maf hz it’s retarding at and go out and repeat and see if it’s still there. Keep adding fuel this way until no more KR exists or it doesn’t make a difference and only then you should retard the timing table in ** and make sure the LO table corresponds with the same decrease.
 

pwtr02ss

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Last night i did some thinking about some valvetrain noise i hear under light load at around 3200-4000 rpm.
It's been bugging me a bit since it seems to be getting louder.

Maybe i need longer push rods, lifter is being difficult/faulty, or maybe I need to ensure i fully torqued them down all the way.

The sound reminds me of my old S10, if you get the throttle cable routed incorrectly, it can pulsate some engine noise right down the cable into the passenger compartment.
but there are no cables that could do that in the tahoe...

Other option is the hard line i used for the catch can.
but i have that setup with rubber flex joints, and lined with the same stuff anywhere it makes contact with anything hard.
Mostly to prevent wear, but it should also sound deaden.

Then i remembered something, the 1.8 rockers.
I did some reliving of the valve cover to prevent this issue.
It's possible that in this area of rpm, i have enough oil pressure that the rockers are moving up more and hitting the valve cover.

I did some driving around last night to repro the sound, and with the windows down.
It's louder outside the truck than i thought, but it's still hard to hear unless i'm driving against a wall or another car.

If they are even slightly coming up and hitting the valve cover, then there is my issue.

So my task later today, pull the valve cover on the driver side.
if I see signs of contact, more reliving.
and I'll probably do the same to the passenger side if it's found.

from there, I'll probably bite the bullet and order some spacers and the updated valve cover.

I'm crossing my fingers that this is the issue, but i doubt I'm that lucky. :hahano:

:violin2:
Mine has that noise when the oil is fully warmed. Longer pushrod is the solution for me I think.
 
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Just Fishing

Just Fishing

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Mine has that noise when the oil is fully warmed. Longer pushrod is the solution for me I think.

Kinda what i was originally thinking.
I have a set of 7.4s, but they did pump metal.

Hoping it's just the valve cover.
Things came up, so I'm hoping to tackle the job tomorrow....
 

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