Ok first off, nothing seems to be wrong with the motor after the swap. Thanks to Hemifever Tuning and a lot of time researching for the right parts everything started up and worked fine on the first try. After burping the cooling system I went out for a test drive. At first everything seemed fine, but once I got up around 50 mph the truck starts pulsing like its jumping in and out of lockup really fast. Got a new tcm tune from HF and it still has the problem. Im not really sure what is going on and Sean says he's never seen this before. Any help would be much appreciated, cause I kinda need this to run by monday for work.

 

What cam are you using

 

How big of an rpm jump are you seeing?

 

268 comp and theres not really a rpm jump.

 

Ok, so since a 268 has to have the PCM tune, you don't have to have the TCM tune. Have you tried to do just the PCM tune without the TCM tune or are you trying to use the TCM tune to try to correct the issue (if it is actually the trans)

 

I'm trying to use the TCM tune to fix it, but now that I've driven it more it seems like the timing is off because it doesn't have the power that it should. Does this mean I need to tear into the motor again or can I check it without pulling the timing cover?

 

Did you use my tutorial in the How To/DIY section and follow the steps/pics?

And yes, if the timing is off, you have the remove everything all over again. Trust me, it sucks as I too had to do that once....... ONCE

 

I followed the DIY to the letter but I may have gotten off by a tooth. Gas mileage is that of a tank and theres no power. Would i have to remove the rockers again to get it right or will it cause problems?

 

Won't have to remove the rocker shafts but will have to pull the coils and valve covers.

Only reason to remove the rocker shafts is to release the lifter tension through the push rods from the rocker arms. But you aren't removing the cam so no need to do all that.

 

Alright. I'll dig into it again once I make sure its not just a push rod out of place.