Hey. my friend who tuned mine. Say PCM already max out memory I cant go over 20 psi. Only run 15 psi right now. He say suggest get MegaSquirt computer that allow more control. I never hear of this. It really new to me. See if anyone can explain me little better. I been research about megasquirt. My truck is 2006 model. I just don't understand why max out on my pcm. It cost around 1500 to get megasquirt. is anyone who have same issues? I run turbo 15 psi on tms iron 5.7 as well. Hope hear from you soon.

 

That doesn't sound right.
There's several of these trucks running more then 15psi.

 

doesn't the 06-07 OS have some weird quirks?

Yeah, but in general terms, the pcms do not have any boost limit.

 

You need to get a different MAP sensor. You probably have a 2 bar Map and need to move up to a 2.5 Bar sensor for 20 PSI

 

I had to scale my 05. Kept hitting rep under wot. Scaled computer and all fixed.

 

I asked him. Say 2 bar max memory on my 06 PCM??
He say -The pcm in your truck only has about memory for 2bar

 

I'm running a 3 bar map sensor, stock computer. It's running fine.

 

Your computers OS might only support a 2 bar map upgrade but you could still scale the table to work for boost above 14.7 PSI.

He is correct in saying that the computer is supported for a 2 bar setup but it's not really out of memory. You can work around the issue if you know what to do.

 

Want to update with y'all. Want to be sure if anyone give me correct or disagree before I end up spend out on tuner again. So tuner told me what to do. He will change 3 bar map? Change pcm to model 2004. My truck is 2006. Also he say need change Dbw tac module to match 2004 pcm. Then tune on efilive. Turn up 20 psi where I want to boost at 20 psi. He charge me $800 for all and tune. But why have to change Dbw gas pedal
To 2004?? Is that true?

 

Not sure why he wants to move you to an 04 pcm. A 3bar map, retune is all you should need providing the injectors are enough.

The tac module isn't dependent on the computer, it's dependent on the throttle body. If you change the throttle body, you have to change the tac module and put in the correct values for your "new" tac module else you'll brick the pcm.

Who's doing the tuning? PM if you want. If it's who I think it is, bleh.