Overboost or fuel cut? Remedies?
 

Hi there. I've got a 1994 Impreza WRX with the following mods - fully de-catted exhaust, ported headers, induction kit and a Walboro 255 fuel pump.
When the car is warm it will boost fine in first and second gear. However, when reaching third gear and roughly 4000 revs, it feels as though someone is standing on the brakes. If you back off and then put your foot down again, it's fine.

It does this in fourth and fifth gear as well. I've got an HKS Fuel cut defender to fit but was wondering if anyone had any ideas on what could be causing this problem? I was thinking about putting my name down for the group buy on the ecu upgrades for the 92-96 Impreza, hoping that it might sure it.

Any infomation or input would be greatly appreciated.

that will be fuel cut mate, because your exhaust mods are causing the boost to spike over the standard fuel cut which i believe is 14.5 psi.if you fit the defencer you will stop the fuel cut but most likely cause det which will melt you pistons! do things properly and get a remap in the form of a chip or aftermarket ecu, trust me it will save you money in the long run!I have a vos chip fitted with the same mods as you and im running 16.5psi with fuel cut raised to 18.5psi and it will map for uk fuel aswell. (pm me ive got a spare vos available if your interested)