What RPM does a stock IX reach peak boost?
Mar 8, 2006, 10:09 AM
#1
Evolved Member
Thread Starter
iTrader: (12)
Join Date: Jan 2006
Location: salt lake city
Posts: 888
Likes: 0
Received 0 Likes
on
0 Posts
What RPM does a stock IX reach peak boost?
I am basically just trying to figure out at what rpm a stock Evo IX reaches full boost, so any help would be appreciated... now here is the reason I ask- I made the mistake of installing my K&N drop-in panel filter before drying it... (besides the filter everything else is stock for now)... i thought the car wasnt running as well so I went searching for answers and found out about drying the filter and spray cleaning the MAF sensor. So now I have used the CNC brand MAF sensor cleaner and dryed out my filter and re-installed it, and now I am able to reach the original 19-20 psi on my IX MR that I should... around 4500 rpm, but I could swear it spooled quicker than that before, like at a lower rpm. I just bought the car a week ago brand new and broke in the miles before my filter install... so what I cant tell is if I am imagining things and that it is reaching full boost at the appropriate rpm and that I have become desensitized to how fast the car is, or if it really should be peaking earlier. I have searched all over evolutionm.net but cant find out what rpm a stock Evo IX is supposed to reach full boost. The other thing that makes me think something may be wrong with my sensor is that the first few minutes I drive my car it wont even boost to 1 bar... but after like a few miles it will reach 1.3-1.4 bar of boost, but not until 4000-4500rpm. Is my MAF screwed up or is this normal? Any idea where I can find out what rpm peak boost should be reached at? Thanks in advance for any help and to anyone not flaming me for being a newbie on this site- 
Last edited by DJ Brett B; Mar 8, 2006 at 10:11 AM.
Mar 8, 2006, 04:31 PM
#6
Evolved Member
Thread Starter
iTrader: (12)
Join Date: Jan 2006
Location: salt lake city
Posts: 888
Likes: 0
Received 0 Likes
on
0 Posts
Yes- for sure if you replace the factory housing when you go with a CAI or ram air type intake system, but it was my understanding that drop-in panel filters (K&N, HKS, etc...) didnt need a retune... maybe they do (?) I'm about to go try dropping in my stock filter and see if I can reach full boost around 2700... I'll post the results-
Trending Topics
Mar 8, 2006, 05:39 PM
#8
Evolved Member
Thread Starter
iTrader: (12)
Join Date: Jan 2006
Location: salt lake city
Posts: 888
Likes: 0
Received 0 Likes
on
0 Posts
Thats what I thought.... although the stock filter seems to be working better now that I dropped it back in.... so now it BEGINS to build boost at 2700 rpm, but doesnt hit 1.3 bar until 4500 rpm or later. Is this normal? OR, should it be hitting 1.3 bar by 2700 rpm? Anybody know?
Last edited by DJ Brett B; Mar 8, 2006 at 05:41 PM.
Mar 8, 2006, 06:05 PM
#9
Evolved Member
Thread Starter
iTrader: (12)
Join Date: Jan 2006
Location: salt lake city
Posts: 888
Likes: 0
Received 0 Likes
on
0 Posts
I just read a couple of reviews on the IX and they said that all 289 lbs of torque are available at 3500 rpm.... so something has to be wrong with my car... guessing its my MAF sensor
Mar 9, 2006, 10:19 AM
#10
Evolved Member
iTrader: (1)
Join Date: Jun 2004
Location: Plano, TX
Posts: 1,270
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by DJ Brett B
I just read a couple of reviews on the IX and they said that all 289 lbs of torque are available at 3500 rpm.... so something has to be wrong with my car... guessing its my MAF sensor
-M
Mar 9, 2006, 06:05 PM
#11
Evolved Member
Thread Starter
iTrader: (12)
Join Date: Jan 2006
Location: salt lake city
Posts: 888
Likes: 0
Received 0 Likes
on
0 Posts
Thats true- unfortunately I dont have the funds right now for a dyno, but I did re-clean the MAF sensor with the spray cleaner this morning and had the dealeship check the sensor and run a boost test today.... they couldnt find anything wrong and it does seem to be running right today since I re-cleaned the sensor... probably just got a little more oil from the K&N on the MAF sensor since the first time I cleaned it... I swear it runs better with the stock filter... weird! 
Probably stick to the stock filter til I get dynoflashed! Thats for your input guys!
Probably stick to the stock filter til I get dynoflashed! Thats for your input guys!
Mar 9, 2006, 07:47 PM
#12
Evolved Member
iTrader: (4)
Join Date: Apr 2002
Location: chicago area
Posts: 906
Likes: 0
Received 0 Likes
on
0 Posts
it is nortoriously easy to over oil a k&n filter. use just a tiny bit of oil on each pleat. then let it sit and soak in to the rest of the pleat for a few hours befor useing
Mar 10, 2006, 04:58 PM
#13
Don't know about you, but I hit full boost around 3500rpm and the car responded even better after I installed a Works high flow filter. Its not overoiled from the factory and has a tight fit. Went back to the stock filter to see if its not my head, and sure enough, the car is more responsive with the higher flowing filter.
Mar 11, 2006, 02:16 AM
#14
Newbie
Join Date: Jan 2006
Location: New Zealand
Posts: 29
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by DJ Brett B
The other thing that makes me think something may be wrong with my sensor is that the first few minutes I drive my car it wont even boost to 1 bar... but after like a few miles it will reach 1.3-1.4 bar of boost, but not until 4000-4500rpm.:
The IX has boost limit when the car is cold to around 10psi and it is gradually increasing until you get to normal operating temp. My IX is a Jap spec and gets to full boost 22-23psi (on a crap autoguage) at around 2700-3000RPM. The best way to see what the boost is doing is to go on the highway at 4th or 5th (in a 6spd car) and to put the foot down from 2000RPM and see how the boost builds up. as for the filter, I doubt anyone could feel the difference between a stock to high performance filter when driving the car, as it is at the most about 2-3HP. Usually the only difference is that the intake is louder and the car sounds faster. The weather will have a far more noticeable effect on the car's performance than an air filter.
You will also find that at around 5500RPM the boost starts to drop and it gets down to 13-14spi at 7500RPM this is built in to the ECU boost table so that the car does not pass the spec 289FWHP. I have installed a boost controller and set it to factory boost and the boost holds up longer at 23 and only goes down to 19psi at 7500RPM, now that is noticeable!!! Just a word of caution, if you want to do that stick to a reputable electronic boost controller (eg, GReddy PRofec B-spec 2)
NB. Why did you oil a new K&N filter in the first place? You only need to do it after a clean which is at 50,000mi.
Mar 13, 2006, 07:27 AM
#15
Evolved Member
Thread Starter
iTrader: (12)
Join Date: Jan 2006
Location: salt lake city
Posts: 888
Likes: 0
Received 0 Likes
on
0 Posts
Thanks IX Wagone- that was the kind of response I was looking for 
My IX wont hit full boost until after the 4K mark, but I'll try your advice about starting at 2k in 6th gear and I'll see where it boosts. The dealership told me it was fine, no boost leak or MAF sensor problem.
Actually I didnt oil the K&N filter, it came out of the box really oily so I dried it out. THey need to go easy with the oil! Thanks again!
My IX wont hit full boost until after the 4K mark, but I'll try your advice about starting at 2k in 6th gear and I'll see where it boosts. The dealership told me it was fine, no boost leak or MAF sensor problem. Actually I didnt oil the K&N filter, it came out of the box really oily so I dried it out. THey need to go easy with the oil! Thanks again!