I have a Nelson Tune for my mods below, mainly the cam/headers. How much performance could I be losing if im seeing KR as high as 8.0 at WOT. I know KR is certainly not a good thing to see at any time. I like my Nelson Tune and this is my second cam Ive tuned for from Allen, the last one was the MS4 and I never saw any KR anywhere in the RPMs.

 

8 is pretty high. I can't really say how much power you're losing but that is definantly a pretty good spike.

You do have a 01-02 pcm right? Also you did do a crank relearn correct?

I was seeing tons of KR before I did a crank relearn and then it all went away.

 

I do have an 01-02 pcm. Interesting, I never even did a crank relearn after the recent cam swap, because it didnt appear i needed one after the MS4 cam...just plugged in the pcm and cranked over.. so a crank relearn could clear up all that KR?

 

Not saying it will for sure but when I swapped to mine it was pulling timing like crazy and I was seeing around 6* KR. I did a crank relearn and BOOM it felt like the truck gained 30 rwhp

 

im on my way down to the garage..... ill be back with results!

 

Yeah, 4* is like the factory max for knock retard, so he probably changed that to 8* max. Your losing a lot of power with that much timing being pulled.

 

I want to say that all of the gas tunes I've seen have KR max set to 8* in PE mode, so at WOT, that's pretty much normal.


As to whether or not you're losing power from the timing being pulled... Maybe, maybe not. If the timing is excessively advanced, then pulling 8* may still leave you at a point where peak cylinder pressure is occuring. It's certainly not the most efficient before the spike picks up, but it may or may not be after the KR spike occurs.

 

I couldnt get a hold of the buddy of mine with the obd2. What kinda obd2 or tec2 can i get inexpensively to do the crank relearn? Im sure ill need it in the future.

 

HpTuners or EFILive

 

Ive built 3 motors and swapped 4 cams and have never done a crank relearn. Never a problem yet.

8*s is a lot of timing but like dc said, it wont matter if the timing is advanced too much anyways. I would say that you are losing power though.