Question about Installing a boost controller

akito

Keep Laughing.You're Next
Jul 31, 2006
1,568
0
0
Springfield/Va
I'm having fuel cut issue at 9lbs and it is cutting off at 5500. I'm going to check if i have a boost leak 1st but i just want to kno can i install my greddy ebc profec bII and turn boost down to 8 and not have that problem?
I think it is a leak because im on stock turbo and it is cutting off at 5500. But its just like fuek cut. So if i turn down the boost and i can hold it til red line then that means it was FC n not a leak. Cause i remember fuel cut is at 12-13 lbs?
So i just want to kno if there would be a problem with installl the ebc n turning down the boost.

Mods: intake, raptor racing ddp, test pipe, apexi N1 catback, auto 89 na swap with gte electronics.
 

OneJArpus

Supramania Contributor
Jul 1, 2005
2,798
0
0
40
Newark, New Jersey, United States
IIRC boost cut on a 7m is 12. I've always ran 10 no issues when i had my 7m. Installing a BC will not allow you to lower the boost either. Your car is doing 9psi because it is getting that from flow. Do a boost leak test and i'm sure you'll find some and when you correct them you'll actually be at 12 psi. I got 9 psi with just a catback.

my buddy had similar mods and was doing 12psi ez and hitting fuel cut
 

CyFi6

Aliens.
Oct 11, 2007
2,972
0
36
Phoenix
www.google.com
Fuel cut is just based on flow, so PSI is irrelevant. Depending on all the variables of nature (altitude, temperature, humidity etc) and the mods you have you will hit fuel cut at different pressures.
 

Treecesmk2supra

New Member
Jul 27, 2009
18
0
0
Jackson, TN
i run 10psi no fc!! i tack it out!! ok i got my boost cont. turned out as far as it will go. and only getting barely 10 psi...and have a aftermarket bov...dont know what kind..looks cheap but works great, and 3in megan racing full exaust from elbow back. could my bov need a stiffer spring??? or is it a boost leak???
 

radiod

Supramania Contributor
Dec 13, 2007
1,342
0
0
37
Abbotsford, BC
CyFi6;1568113 said:
Fuel cut is just based on flow, so PSI is irrelevant. Depending on all the variables of nature (altitude, temperature, humidity etc) and the mods you have you will hit fuel cut at different pressures.

Consider this first. Everyone will hit fuel cut at different levels because no two cars are going to flow exactly the same through the intake. Having things like an upgraded intercooler or pipes will lower the threshold because it flows more at lower psi. Even weather and location can make a difference of as much as a couple psi depending on the temperature, humidity, altitude. Rule of thumb, the closer you are to sea level and the colder it is, the quicker you'll hit fuel cut. Typically my car will hit it at around 11psi with upgraded IC pipes, but if it's a really cold day it will cut as low as 9psi.

A boost leak test is never a bad thing to do. If you think you might have a leak, it's not going to hurt anything by doing this :)

Boost controllers can be finicky too. My buddy has the same boost controller and depending on the day it will hit 10psi on the dot, another day it won't get higher than 9psi, and other days it will creep until it hits fuel cut. Yes, a lot of that has to do with environment too, but just saying you can't expect exactly the same results with keeping the same settings all the time. You might have to tweak it here and there depending on the day if you want the peak performance. If you don't want to have to tweak, find a setting that is going to be reliable regardless of the temperature, etc and stick with it.