Ok I've got an 03 evo 8, bone stock minus a fujita intake, with upper an lower intercooler piping. Anyhow I'm only running 16 pounds of boost, I read there supposed to be around 17-19 stock correct?? Well I'm about to install a halmann boost controller, and I was wondering with the factory fuel mapping would I be ok to set the boost to 19- 21 pounds or so with no tune?? I'm planning on taking it to English racing here in a few weeks hopefully for the tune but was curious as to the info you guys have.Any answers would be greatly appreciated

 

Factory map is very rich so you "should" be good until you go and get a real tune.

BTW its been 4 years since my evo seen stock boost so I have no idea what stock boost is. 16 psi seems kinda low. Is that at redline or at peek boost? You might have a boost leak after installing the UICP and LICP. I would to a boost leak test first.

 

There are a couple reasons why you could only see 16psi. Since you have an 03, you also have the plastic divertor valve which is known to leak. Another possibility is a boost leak somewhere since you have upgraded IC pipes. If you're going to install a MBC, I would highly recommend a tune and a boost leak test. There are a couple gaskets in the throttle body that are also known to leak - I know mine did.

But definitely do a tune with the MBC.

 

Awesome thanks guys, I was thinking I might have a boost leak, it runs very smooth and it peaks at 16 pounds, I will do a boost pressure test