Specs:

Bone stock cept an MDC and Jestr Tune.

My boost isn't consistent through the gears. And I don't mean off by one or two PSI. 1-2 gears it hits about 20 then drops to 19psi, 3rd is a tad higher and 4th a tad higher again. 5th hits 25 and settles at 24 all day long, which is too high for my setup.

My questions are:

1) is this normal? I know others holding consistent 22-23psi in all gears (different mods)

2) is it my tune? We have had crappy weather so I haven't been able to log it and get him to tweak it yet

3) is it because my stock exhaust?

I don't remember what my stock tune did and I can't put it on right now cause my laptop is broken, I will have it back soon and I can play around, but I am curious if there is a reason for this odd behavior that anyone can chime in with.

The MBC is the Dejon Tool. Its got me thinking maybe an Electric boost controller would be better and MUCH more consistent, but I know many people here are running the dejon. So throw some ideas at me.....

 

boost is higher in higher gears with a mbc. an electronic boost conroler is much more consistent, but way more expensive

 

As the poster above me said boost will be higher in the upper gears. Weather plays a big part with boost changing. Colder weather higher spike warmer lower spike. An MBC or EBC will help reduce spike and taper more so with the ebc but some say the $ isnt worth it. I use an ebc and love it my boost is very consistent

 

That would explain why a friend of mine with a few different mods gets consistent boost. He is still using the stock solenoid and can run 22-23 in all gears all day long.


So this much of a difference is typical due to the MBC versus a computer controlling it? If thats the case I think I'll be looking into going back to the stock setup or an EBC.

 

But see I am running an MBC. I only spike 1 psi above where I settle (if my gauge is that accurate) what concerns me is that I want to hit 22-23 in 3rd and forth cause thats what I am in more around town. But I barely tap the peddle on the interstate and that setup has me at 25 spike settling to 24 psi in fifth.

If I can get a decent MBC that will make it withing 1-2 psi in all ranges I would be happy.

Is it maybe just that I am not building enough boost in the lower gears period? And not my tune or MBC at all? I noticed that the MBC holds boost MUCH better than it did stock. But I didn't expect such a huge range in the gears.

 

I have a Jestr Tune and Hallman MBC...in 3rd WOT I hit 19psi, in 4th or 5th 21psi spike. So it sounds right. Higher gears = more load = higher spikes. Most importantly the boost HOLDS tight! No tapering.

 

Yeah my 4th and 5th is MUCH different than yours. Oh well. Maybe I will jsut turn it down for now and look at an EBC. Not a fan of the lack of control with an MBC. Sure it fixed the taper, but I want to set it and forget it.

Thanks guys.