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pitmac
23-07-2008, 09:33 AM
I have fitted a 3" exhaust with 2.5" pipes to the turbos on a Galant E84A 6A12TT. I now have boost spike of 22PSI in 2nd and 24 PSI in 3rd Gear.
I'm using a manual boost controller , ball and spring type. Cannot get the boost down .
I was hoping one of our Kiwi members might be able to help.
I used this forum as i own a EC5A and there is no club for the E84A Galant

Wodjno
23-07-2008, 09:38 AM
I have fitted a 3" exhaust with 2.5" pipes to the turbos on a Galant E84A 6A12TT. I now have boost spike of 22PSI in 2nd and 24 PSI in 3rd Gear.
I'm using a manual boost controller , ball and spring type. Cannot get the boost down .
I was hoping one of our Kiwi members might be able to help.
I used this forum as i own a EC5A and there is no club for the E84A Galant

Make sure the MBC has the pipes connected properly.. Or that 1 of the pipes is not split.. Either will give you boost spikes like that /yes
Also the ball/spring maybe jammed inside the MBC..

Turbo_Steve
23-07-2008, 04:55 PM
Another possibility is that your new exhaust is interfering with the wastegate assembly in someway: either too much flow accross the wastgate outlet, preventing it from bypassing the turbine, or a piece of metal actually preventing it from opening.

Is boost stable if you "drive around" the initial spike, or does it simply climb and climb as soon as the throttle is past 50%?

Goku
24-07-2008, 04:19 AM
Yea, by the sounds of it you are free boosting, the E84A's usually tap out at 25PSI on the manual ones, and 16PSI on the auto's.

They will always initially "spike" before leveling out. like say 22 down to 18 at higher revs.