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I have a series 4 with the stock turbo and 3" exhaust.
I installed a boost controller yesterday and in second and up I hit 10 Psi however in 1st I only hit 6 psi is this normal? Is there a way to get the full 10 psi in 1st gear?

The other thing is in 2nd gear it hits 10 psi stay for a bit then drops back to 5 psi, (I have not been able to full test third gear but it seems fine), again is normal and is there a way to maintain the boost for longer?

SpeedFreak03

What RPM are u at in 1st when u only get 6 psi? In 2nd gear what RPM does it drop at, or is it different every time? Did it do these things before u installed the BC? On a side note start thinking about fuel management now that u have an exhaust and BC...

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I have never noticed the boost dropping before, but first has always held 6 psi fine.

2nd gear may be losing boost at around 5 -6 K, not sure if it is the same every time.

Yeah, I know I will be installing a microtek when the funds drought is over

ilike2eatricers

Do you have a fuel pump or FCD?

driftaholic

Sounds like you have boost creep issues.

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FCD, but there is no slow down on the revs
As far as I understand the FCD will pump in enough fuel for 8.6 psi at X revs onces you go over about 2 psi, but Mazda run it rich enough to run up to 10 psi any way.

Slacker7

iTrader: (2)

2 things.
From the symptoms you have described.

You have a bleed valve type boost controller, you just have to live with that.

or
you have a regular ball and spring type boost controller and you have it set too low. The reason you are boosting more in 2nd gear and other gears is because you have boost creep.

Even you have set everything right in first and second boost will touch 10psi and drop off because engine is drawing in more than the turbo can handle (turbo efficiency drops off).

It is recommended you get your fuel pump rewired, FCD(this is a grey area as some people recommend not to used FCDs), Fuel injectors cleaned and flow tested when running the car the way you indicated.
Also alot of people have and are having luck with an upgraded fuel pump.

ilike2eatricers

What other mods do you have if any?

The FCD tricks the ECU into thinking that you are not running above the stock preset boost levels. It does not add fuel to anything. Factory fuel cut can vary from 7.5-8.5psi depending on series. Just because you have a FCD does not mean that you flow enough fuel to support that much boost.

Honestly I think installing the boost controller was a mistake because it cannot lower boost levels and seems like you are boost creeping already.

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Slacker7 is the issue with first gear normal or should I be hitting more than stock boost here?

So if I was to port/use an external waste gate it would hold the boost better in 2nd?

Slacker7

iTrader: (2)

Do you have a boost gauge? I will assume you do since you know what boost levels you are running.

If you are running 6psi you probably are running stock boost(unless you have a digital read out of boost the max boost of 5.5psi will be +/- 0.5psi so 6 psi is within that uncertainty range.

What you should do is keep an eye on your boost gauge when you pushing the car in 2nd gear and watch the boost pattern. Does boost quickly builds up to 6 psi and slowly "creeps" to 10psi?(now you know where the term boost creep comes from) If it is then you have set your BC too low.

Again, what type of BC do you have?

and again just to make sure sorry to sound like a broken record but safety first

It is recommended you get your fuel pump rewired, FCD(this is a grey area as some people recommend not to used FCDs), Fuel injectors cleaned and flow tested when running the car the way you indicated.
Also alot of people have and are having luck with an upgraded fuel pump.

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3" front mount, turbo smart blumback BOV, lightned flywheel, clutch, HKS FCD, turbo smart boost controller, full 3" exhaust with 3" high flow CAT.

Yeah I know tha FCD does not add more fuel, however the stock ECU runs richer than need be.

You should also be able to use the BC to go back to stock boost, but no lower, and well I don't see the point of running lower then stock boost

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3" front mount, turbo smart blumback BOV, lightned flywheel, clutch, HKS FCD, turbo smart boost controller, full 3" exhaust with 3" high flow CAT.

Yeah I know tha FCD does not add more fuel, however the stock ECU runs richer than need be.

ilike2eatricers

The reason you want to port your wastegate is so that you do not boost creep. The stock wastegate is not large enough to vent off excess boost that you are creating with your mods. If you port the wastegate you can hold your boost to certain levels safely without creeping depending on how large you port.

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I'll pay more attention to it, but it seemed to come on rather quickly.

The BC is a turbo smart Gated Boost Control Valve (www.turbosmart.com.au)

Slacker7

iTrader: (2)

Okay.. if you have the GBCV from turbosmart you have a ball and spring BC.. now what you have to do is check the boost pattern. Were you hitting 10 psi before you installed that thang

Slacker7

iTrader: (2)

Actually after reviewing that boost controller I have come to the conclusion that it is an over-glorified bleed valve.

ilike2eatricers

Incorrect. A boost controller can only raise boost not lower it at all. The full exhaust that you have already puts you above stock boosts limits. The only control over how low you can hold boost is your wastegate.

I didnt see an aftermarket boost gauge listed as one of your mods. I recommend you get one as the FCD will make the stock boost gauge project inaccurate readings.

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Yeah I have one installed, just forgot to list it

J-Rat

iTrader: (2)

Actually, you might want to check the Twin scroll actuator and if thats operating normally, then you just have a crappy S4 turbo. They love to fall off at higher RPMs.

Jarrett