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Opinions needed - Performed Optical Bump

Well today I decided to un-do the optical bump and set the timing properly. My goal was to get as close as possible to a -1.45 or so like @MrMarty51 has. Well got the top off the IP and loosened the t-40 bolt to move it back. That’s were the problem started. I can loosen it and move it back to my scribe mark but as I slowly tighten the screw it moves back where it was !!! I tried several times even with holding it into place with another screwdriver while tightening up but it jumps back as it snugs up as if something under there is like notches lining up. What’s further interesting is if it hold it over further that where I scribed it just to hope it with settle down at the mark. The screw won’t tighten just turn roundy round!!!
Any thoughts about this??image.jpg
 
I’m kinda questioning if I even moved it before when I did the bump. I had scribed two marks one on both sides of the top saddle thingy for the OS The mark on the other side is lined up with the top saddle thingy!
 
I sucked the fuel out of the hole and tried again. Still the same. It must be notched under there! But in doing so I noticed I can easily move the entire OS side to side with it being tight using a flat screwdriver. The “v” notch thingy moves with it too. I hope that’s normal
 
I moved it straight up center as it looked to be when I pulled the top. Going back together with it and if all is good I’ll do the timing
 
Put the IP back together didn’t bolt down the upper intake on yet. Cranked her up with the laptop connected and all seems normal
With my tdc offset at -.7 if I’m not mistaken I would need to tweak the IP over towards the passenger fender just a tad to get closer to -1.45 ? Then run it up to operating temp and do the relearn. Correct me if I’m wrong

my offset numbers were at -.44 on the original pcm
 
Just got done with the relearn procedure. After about the third try. ( rotating it towards the drivers side this time lol. I got -1.58. Should I try again once more to get closer to -1.4ish?
 
MrMarty51 said:
I would wait and see what others say.
How does it start now with the timing where it is ?
Seem to cruise okay ?
And accelerate too ?
Click to expand...
it seem s crank up just fine and idles good. I haven't taken it out on the road yet. I figure get it close as I can to what yall think is best and run it for the week and see if there is any improvements.

BTW I know... dumb question.. what should I see on this kind of timing change from mostly stock timing? any better fuel economy or power increase?
 
The fuel economy on my truck increased a mile or so to the gallon, maybe a little more. IIRC it was about 18 MPG and now slightly over 19.
I dont know, that too may be why it does not run at 195 degrees coolant temp on a very hot day, was right on 200.
Maybe if the timing was backed down slightly the engine might run cooler.
 
I like to have the performance when I need it, on the flip side I want good mileage so long as I can actually keep my foot off the floor lol.

I've often thought about the #9 resistor to help, but I have been on the fence because I didn't want my truck using the extra fuel all the time. I always thought it would increase the fuel a tiny bit at all times. since I have been reading and learning some on "DIY tuning" I have seen the tables in the software for fuel vs throttle position and rpm, and the other tables in there for each resistor. it looks as if the different resistors makes the pcm use that slight more or less amount of fuel at all times like a multiplier in the calibration tables for the tune.
 
I dont really know how the resistor factor works.
I have read, that no matter how many ignition cycles the pump will not read a resistor with more or less resistance.
Someone in the know please correct this myth for Me.
 
So the resistors purpose is for fine tuning the IP so they all meet the same spec. The OBD1 reads the resistor every 50 key cycles IIRC. The OBD2 won't read the resistor until you do a relearn as proved by Turbine Doc and his quest to prove steaksauce wrong on his adjustable on the fly fuel trim he was selling.
 
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