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Just looking for advice.

I have installed a profec B (series 1) on my Rb25DET in an R33 4 door with auto and it seems to work OK, but the boost is comming on later than when I had a bleed valve.

It holds boost well, and my dyno graph is smooth and well shaped, (and produces a few more kw than the bleed valve and has a much better shape) but it comes in much later. I have set the ballace to 100% sharp.

Has anyone else come across this or have ideas on how to solve the problem.

PS. Vacume pump is located on the strut tower next to the original boost solioid, and the vacume line is tapped off of the rising rate regulator line (front of plenum)and fed back through the fire wall behind the right wheel.

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Playing with the sharpness controls can alter when boost comes on.

I wouldn't recommend 100% - After countless adjustment on the road I found that around 1/4 produced some of the best results for my old r33. Every car would vary though. Start at 50% and work up or down from there.

You really need to see when boost rises nicely and best holds at xx psi when you are on full tap. Alternatively if it comes on too quickly it will simply spike, and drop off at high RPM. I could see it exhibiting this on the boost gauge.

Once you find the perfect medium its a great EBC, but I think a lot don't bother playing with this control properly.. which is very important to get the best adjust.

Really need to set it on the dyno - as its pretty dangerous to set on the street and you can only really notice these things under flatout acceleration. I would also note that quite a few places I took it to had absolutely no idea what it was even for :-s

But I have sharpnes set to 100% and boost still comes on LATER than my old bleed valve.

It holds boost perfectly, and has been set up on a dyno, but looking at my old graph and new graph it shows the power is down (through most of the rev range) as boost comes on later.

wreckedhead I am guessing you bave the seec II controler, mine only has a low and high boost button without a readout. Have you been to http://www.greddy.com/ for help. I think there is a pdf that mentions this sort of thing. (you can change the dip switch combination to make an adjustment)

there are 3 vacum lines

2 are from the actuator to the under bonnet unit (???) to the inlet pipe, but the third taps off of the inlet plenum and runs direct to the control unit inside the car (- this is the line I have tapped off of the fuel regulator).

I have used the shortest length lines possible between the inlet pipe and actuator (about 15cm each)

I had no probs with mine.As Predator said start with the balanceat 50% and work from there.I found that about 75% worked best with mine.Sounds like you it all connected up right.What I did with the hose that goes to controller in the cabin was tee into the charcoal canister,I did'nt really what to get it from the fuel reg.

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