I have seen several posts where folks say the 8.1's like low timing?

How low is low? How far should I go? Motor breaks up in the 2500 to 2800 rpm range. HPTuner scanner shows I am still getting some knock retard in this range. I started with the stock curve from a 2003 suburban and have been adding fuel and taking out timing. AFR's are pretty good, so I am assuming it must be timing.

I have been taking out 1 to 2 degrees at a time. Should I be pulling timing in 5 and 10's instead?

For HPTuner guys, tune file and log file attached. (Also any other bonehead mistakes you find in the tune file let me know)

 

When i was running my 8.1 on the ls1 msd box. I had 28 degrees total and like only 10 degrees total advance otherwise it would ping

 

I think I am narrowing down my problems. I may have several small issues rolling up into a larger one. Bank 2 is running leaner that Bank 1. I have dual widebands on it as well as the factory sensors both are showing Bank 2 as lean. Possible bad injector or bad plug wire and/or coil

I starting with the cheapest fix first. I replaced the plug wires. That helped some, the difference between Bank 1 and Bank 2 is slightly less. I was finally able to make a WOT run, and maxed out the injectors to 100% duty cycle.

New 42# injectors will be here today. I will swap them out and see what happens next.

Just to be sure I understand you correctly, your base timing curve had a peak of 28 degrees and peak of 10 degrees of MAP advance.

Thanks

 

Put a real fuel pump in it.

I was having issues with mine and after installing a fuel pump that had some volume it fixed a bunch of my issues

 

Fuel pump was my first guess. I added a fuel pressure sensor to the data logger and it is holding 50 to 51 psi at WOT. Fuel pump is a walbro 255. If pump becomes my next weak link I will probably go to dual pumps.

 

Is that Raylar's 102 torque cam your running?

 

ah yes your jeep is red right?

 

The paperwork says BP202, but I think that is the 102.

I had a red/yellow CJ3b with a 406 in it years ago. But you are probably thinking about another CJ with 8.1L from Alabama. I have seen photos and videos of it.

This is the current project

 

ha ha thats kick ***, so 2 jeeps with 8.1's freaking amazing

 

whats the lobe separation on that cam? jeep is badass