Improving Stock 2008 silverado cal.

[LS ROB]

Finally licensed the silverado! DOD gone! Should burst knock be zero'd? I adjusted PE a bit but from the drive log, it may need more work. What do you all tweak to wake these up some?

my Sil 1.hpt
silvy dod delete.hpl

[blindsquirrel]

PE Min MAP should be 70-80 kPa, you don't need PE when there's no significant load and if MAP is less than that it isn't making enough power to need it.

Spark timing, it can probably safely tolerate copying the .64g row and using that to fill out the rest of the table below (above?) there, or maybe have it fall off by ~2* from .72 to .88. Stock timing is pretty neutered above (below?) there. (those LY5 spark maps are a great starting point especially the light/part throttle stuff, they just need to be un-neutered a bit in the higher airmass rows.)

[LS ROB]

Oddly enough, this thing will not hit .72 airmass. The highest it's ever shown in the scanner is .68 and that was a HARD WOT. I see IAT pulling timing, but its also showing quite a bit of KR at random. Would it be detrimental to disable ETC tip-in altogether or should I try adding to that table to keep it functional? I'm attaching the tune and log to see if anyone sees anything else I can do to improve things.


Rob Sil 2.5 KNOCK DESENSITIZE .90.hpt

24-09-06 08-50-44.hpl

[blindsquirrel]

Uh... why does it show knock when you let off the pedal?

[LS ROB]

Not exactly sure honestly. I thought "tip-in" may have something to do with it.

[blindsquirrel]

Well if it's picking up false knock the thing to do is get under there and find the source of the rattle, not just jump straight to turning the sensors down until it's no longer picked up.

This is some changes based on my LH6, which is possibly a ringer, but it does .83-.85g/cyl all day long (380-385ft-lbs). Up to you if you flash it or just use it for comparison. Not responsible for blah blah whatever.

Rob Sil 2.5 KNOCK DESENSITIZE .90 - suggestions.hpt

screenshot.06-09-2024 20.28.23.png

(Yes it had the engine replaced under warranty before I got it but I checked, they did not accidentally put a LS2 in it.)

[LS ROB]

Thanks! I'll get under there and make sure things are tidied up!

[Tech1340]

Check the drivers side motor mount. Pop the hood and watch the motor while brake torquing it. Pretty common failure.

[LS ROB]

Hey fellas, I appreciate the suggestions. I can confirm that I do have a broken motor mount. I'll get the spark settings put back to stock and get some mounts put in her. How common is the passenger side and trans mount to go bad? Suggest changing them all at once?

[blindsquirrel]

Engine torque puts the driver's side in under tension so it fails first always, passenger side is under compression so rarely if ever fails.

[LS ROB]

Makes sense and is good to know that passenger side is less likely to fail. Guess ill spend the coin to get genuine GM part. I'd hate to do it twice. It doesn't look like it wants to play nice. 4wd.

[blindsquirrel]

...though they are 'hydraulic' and the goo can leak out for reasons other than just normal loading like a rubber/poly mount will. God that crap is nasty. I think it's some kind of silicone and absolutely nothing on earth will dissolve it.