I know this has been covered but I still font understand why someone would run sd over maf. Other then the vented bov. Please any information would be helpful

 

other reasons off top of head:

MAF is an intake restriction

MAF has a maximum measurable airflow

MAF provides a reading of the airflow that is often several feet back from the injectors

I'm sure that there are others.

 

Is it harder to tune on? And what's all involved in switching to sd?

 

Another reason is you make more power on SD and boost leaks don't affect a speed density car.

It can be harder to tune if the maps are not setup correctly.


-Bink

 

Sort of. Setting the system up so that you're ready to tune is about two orders of magnitude more complicated. The actual tuning isn't that different at a conceptual level.

Step One: do a ton of reading. This isn't something you learn via some questions on a forum, no matter how good the forum. This is something that you have to truly understand, assuming that you're doing it yourself. We're not talking about plugging in a hand-held or swapping in an EPROM ECU and attaching a laptop. This is closer to (and please don't take this wrong): if you have to ask, then you're not ready.

 

You have control over load vs. pressure (good or bad)
more freedom with intake plumbing
more freedom with de-EGR'ing and crancase venting
tuning BOV spring rates goes away
idle stabillity
IMHO can be tuned for smoother, less jerkey low speed/ part thottle driving

These are all things I have come to appreciate using V7 SD

 

How easy would it be for me to convert considering I have a JDM Evo VIII that has no map sensor from factory?

 

Will different altitude atmospheric pressure changed have a big impact on things, because I drive about 80 miles a day to work from high elevation to low elevation