Call me batsh**t crazy...

[grimmechanic]

So, I acquired a 2004 F150, 5.4 3v, 4R75E, 4wd for $600. Has 200K miles. Trans was roasted. Engine seemed to run fine. Fortunately for me, I have a friend that sold his transmission shop and does a little side work out of his garage. When we pulled the trans, I thought I should probably replace the cam chains/phasers, etc. Good thing I did. The guides were in the oil pan in many pieces. Amazing this thing didn't make any cam chain noise at all... I had the brilliant thought of "re-timing" the cams in order to allow the phasers to advance the cams as well as retard them. I did my homework and checked to see if the valvetrain would tolerate the cams being advanced by one tooth. Cam sprockets have 42 teeth and one tooth equates to 17.14 deg of advance relative to the crank. At TDC, there was a boatload of piston to valve clearance. Sooooo... I went ahead and advanced the cams 1 tooth, reassembled everything, and slowly rolled the engine over by hand to make sure there was no piston/valve interference. Lo and behold, after getting the rebuilt tranny stuffed back in, it fired up! But as you can guess, instant CEL for cam timing and horrible idle quality. Would not stay running. I went through hours and hours of playing with cam timing tables and everything associated with the cam phaser function, and even tried playing with the MAF, IAC, and MAP sensor settings. No joy. No fiddling made a difference in how it ran... until I unplugged the cam sensors. I could disconnect one or the other, or both, and the idle would settle down and it would become drivable. A quick diagnostic of the cam sensors and the wiring/connectors found no issues. But with the cams advanced 17 deg, the engine quickly ran out of power much past 2,500 rpm. Lot's of torque down low.

Now, I am at the point where I've determined that the amount of timing error just isn't something that can be compensated for in the ECU. I'm about ready to pop the valve covers off and re-time back to stock. But, I had another brain fart... I have the old cam phasers and I disassembled them, made a fixture to "re-time" the trigger wheels to trick the ECU into thinking that the cams are timed correctly. And now I'm debating if I should give this a try... the sign of a true masochist.

I'm all for learning things the hard way. It's the way I've learned my whole life. Not saying I'm smart, just stubborn. Any thoughts? Ridicule? Constructive (or not so constructive) criticism? Please make any comments questioning my intelligence as entertaining as possible...

[SiriusC1024]

Re-timing the pickups should work. Problem is how will the VCT know when to advance the cam? It's still going to operate assuming fully advanced as an initial condition. All you're doing is shifting the phasing window.

It's a fun idea, but it's a dumb idea. When you have your timing chain cover off for the third time I think you'll agree

[grimmechanic]

Well, you only have to pop the valve covers off. If you have the cheese-wedge tool, you can block the chain and compress the tensioner and remove the phaser(s) without pulling apart the entire front of the engine. Still not a fun job.

The theory behind re-timing the cam trigger wheel is that the cam timing maps can be shifted 17 degrees retarded and theoretically, the cams would be at the same timing as stock. The only thing that would have to be considered is the max retard is 60 degrees, so the cam timing map cells that are over 60 need to be set to 60 (or less). But, I don't know how the ECU is going to respond with that combination. It's a crap shoot...

So, the goal was to be able to dial in a little advance on the cam timing at lower RPM's to enhance low RPM torque. If it works, then it opens up the possibility of using more aggressive cams and not compromise drivability.

Again, this started off as an experiment on a $600 truck. It's a good thing I have 3 other cars and 2 motorcycles to get me around...

[sook]

I don't have a good answer for you, but I do want to know if it works!

[grimmechanic]

I don't have a good answer for you, but I do want to know if it works!

Well... Ive got two other projects on my bucket list that I need to finish. A 2006 Jeep LJ that I'm swapping a Rubi transfer case in, and a 1992 Dodge W250 that I'm swapping the original auto trans for a NV4500. I get these out of my hair and I'll dive back into the F150...

Then I've got that damn I-6 stroker 4.6 motor I need to put together for the Jeep...

Now, does anyone want to place a vote if I should return it to stock cam timing, or go for the customized cam phaser pinwheel? I'll have to figure out what the stakes of this bet will be...