power drops off after about 4500 rpm

utahalltrac1

New member
Just bought this car, it is a 91 all trac with 91000 miles. I replaced the timing belt, water pump, plugs, fuel and air filters, changed all fluids. I rigged up a cheaper boost gauge and disabled the vsv it was boosting to about 6-7psi I installed a manual boost controller and now I'm running about 12-13psi. The car runs really smooth and has the low end power but when it hits around 4500-5000 rpm's the power drops off pretty bad. The boost pressure isn't spiking or anything so I'm pretty sure it's not hitting the fuel cut. So the question is am I losing fuel pressure or could it be something with air flow? When does the intake runner thing kick in?
 

utahalltrac1

New member
Not yet, the whole system is tucked back under the intake. I didn't have a chance to put the car on a lift. I had some other work to do. Then I have to figure out test it. I'm pretty sure it's the problem though.
 
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