I just got finished installing an Autometer 3303 boost gauge. I am rather surprised to find out that the boost patterns appear to be a little odd.

The car will spike to 21 psi and drop down to exactly 16psi. It is completely stock so I am not sure why it is spiking to 21psi. Could it have something to do with the coldness outside ? It is about 15-20 degrees.

I guess I see now one of the main reasons the car falls on its face after 5k rpm !!! The initial power surge (spike) hits hard and then the boost is pulled back, making the car feel flat in the upper RPM in comparison.

Also I am having difficulty running power to the gauge. I purchased an accesory fuse line so I can run the power directly to one of the two spares in the fuse box. I completed a ground to the bolts behind the driver side knee panel which is under the driver side dash. I tried both spare fuses and both bolts for ground without success.

Below is a photo of the accesory fuse line.

Any help would be greatly appreciated ......

 

I have the same gauge and tapped into the power for the cig lighter. That power is controlled by the light switch.

Do a search!!! This topic has been beat to death. Lots of info our there.

 

What are you boost pattens like ?

 

Anyone ?

 

People get upset when you don't use the search function

 

get a boost controller. that will fix your spiky boost patterns.

 

My boost patterns are just like yours. I think that is pretty normal for stock. It is supposed to peak at 19.5 and drop back to 16. Sometime mine will peak up to 21 like you mentioned. Most of the time I peak at 19.5.

 

Stock boost tapering will go down to 16 psi.

Search function is godly.

 

I was told by the service department the stock boost controller is supposed to spike at nineteen and bleed it down to about fourteen, of course you're hitting higher because of the cold weather. I put in my hallman and set it to nineteen and it pulls good and hard all the way to 6 grand. the stock BOV leaks at about 18 to 19 pounds though.

 

2003EVO you might want to get another stock BOV because mine will not leak around 18-19psi. You might have one of the few Evo's with a Bad BOV. I would contact the dealer and tell them what you are experiencing it might also be a faulty stock Boost control soloniod. Better to get it checked know before you do any mods later.

 

Michael A this is normal for the stock boost control solonoid. The weather will sometime effect the PSI also.

 

Is is a mechanical boost guage? I've been told they can be off by as much as 1.5-2 psi in the upper ranges. Just keep that in mind.

 

myEVOVIII:

I'm pretty sure the dealer wouldn't do anything, because the stock bcs doesn't keep boost at or above 19 (it only lets it spike to it), and since i have a mbc in it, it would be up to me to replace the bov with one that will hold. I want to get a greddy type s for it anyway. (it matches the valve cover, he he)