Just out of curosity can you just write to it without reading it first, like overwrite it?

 

Yes it can be done.What are you trying to do?
Do you have any credits available?
I assume you are using HPTuners as in your sig correct?

 

yes well when im driving around or when i just wanna make a few changes i have been reading the file then changing things then going back and writing calibration,

i was wondering if i can just change and save the current file and write over it without reading it everytime since it takes like 3-4min sometimes to read just a pain to sit and wait on the side of hte road..lol

 

you read the pcm once.

You'll likely never need to read it again.

 

As Bill stated, you pull the tune once and from that point on all you should have to do is write the calibration. You do not need to pull the tune, modify it, and then write calibration every time.

 

awsome. one more question what if i wanna go SD after i select 1barSD on the demo it says to WRITE ENTIRE, would it be the same way just overwrite it if i already have the file saved.

 

You don't need to use a custom OS to use SD only to my knowledge. You should be able to just disable MAF lookup and achieve the same effect. The custom OS just has some nice features for an SD only tune.

But yes, if you use a custom OS you will have to do a write entire.