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Jap spec hitting only 1 bar, after fulldecat and FCD


Matti85

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Before i fitted the decat pipes, i hit fuelcut, i tryed this out 4 times, hited fuelcut everytime.

 

Now ive fitted the FCD, took it out for a test drive, hit the throttle, boost goes to 0.5 bar, and then 1 bar when second comes in. I let go of the throttle and pushed it down again later, now it went only to 0.5 bar.

 

Took the car back to garage, opend the hood and saw one of the smaller vacum pipes loose, put it back and fitted a clip on it.

 

Now i took the car out again, hit the throttle, and the car did the same, 0.5 bar and 1 bar when second comes in, then i pushed again, and nothing happens, no boost at all.

 

Back to garage, opend hood and see that one of the Bigger lower ic pipes is all loose.

 

Now i removed all ic pipes, will give them a clean and put new clips on them and tight them like hell.

 

But man, should it be so hard. And whats up with the 1 bar thing, why do the pipes come loose after the FCD fitting and not before, maybe it overboost and gauge cant keep up, but shouldnt i feel it then, it feelt just like 1 bar. Ive been told i will feel the diffrence between 1 bar and 1.2 and that i did not so i dont thing it did overboost.

So i thought all jspecs will overboost after decated, ive not even fitted a ring, dont need to if it cant get above 1 bar ?

 

Was looking forward to 1.2 bar.

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Do you have a boost controller ? if so it might be set to 1 bar!

 

Check the VSV hoses again mate, I ended up having problems with boosting before that was only due to vsv hoses not been blocked, but I was boosting 1.7 ;)

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You've removed both cats yes?

 

Sounds like it's a problem with a leak somewhere, check and refit all the IC pipes and vacuum hoses first, once you're happy there are no leaks try again.

 

There is a big difference between 1bar and 1.2bar

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No boost controller, ill check all hoses before taking it out again.

But you all agree with me that i relly should go above 1 bar, since it being a jspec, steel blades in turbos but thats all.

ECU alwyas reset after removing - pole on battery, and i always do that before doing any mechanical with the car.

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What he is saying is if you do overboost then you will blow your motor. I would get a BCC and a Boost Controller as soon as you can! It is just a safe and proper way to do it. You also will need it in the future if you plan to make more power. I would be sure to get an electronic BC like HKS EVC 6 or something around that. Well made and well tested! Let me know how things go.

 

Cheers,

 

Joe

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I got Greedys BCC alredy fitted, thing is i think i would feel if it goes over 1 bar, since diffrence between that and 1.2+ is huge apprently, so how can i overboost if i dont feel it ?

 

I hopped i would not need to buy a Controler to raise boost since its a jspec and should reach more then 1.2 when decatted.

 

But i guess im that unlucky million that acutally need a controler to up the boost on my car.

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Mine only boosts to about 1 bar

I hit boost cut several times after fitting my exhaust about six months ago (winter) but no matter how hard i stamp on the throttle now i dont get boost cut anymore.

I bought a fcd after hitting boost cut but never fitted it as it didnt happen very often and now not at all.

 

I thought that once decatted with a decent exhaust mine would boost as far as my restrictor ring would allow (Whifbitz 1.2bar ring) but unfortunately no joy!

 

I seem to be in the same boat as Matt :(

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Put it as one of those things mate. My car ran amazingly well, but would only hit 1-1.1 bar.

It was an incredibly quick road car with that boost and pulled 13.3 1/4 miles all day without any hard launching etc on big heavy 18" split rims.

Enjoy the car and if you're that desperate for 1.2 bar, wind it up with a boost controller...

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When I had the stock twins on my Jspec, and had double de-cats fitted, with nothing other than intercooler, exhaust and air intake mods and FCD, I was hitting 1.25 bar. The Jspecs have the overboost problem due to the weak actuators on the turbos (?). I remedied the problem by putting the primary cat back on. Boost went down to 1.1 bar which is much safer. After that I went single!

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Put it as one of those things mate. My car ran amazingly well, but would only hit 1-1.1 bar.

It was an incredibly quick road car with that boost and pulled 13.3 1/4 miles all day without any hard launching etc on big heavy 18" split rims.

Enjoy the car and if you're that desperate for 1.2 bar, wind it up with a boost controller...

 

:yeahthat:

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  • 1 month later...

well my car was over boosting (16+psi)and hitting fuel cut a fair amount lately wasn't sure what was causing it but worked out that my exhaust(apexi gt) and second decat (hks race only) was too free flowing so put a baffle in to the rear of the back box now runs at 15psi so spot on and no fuel cut

so could it be that you exhaust has to much restriction in it?

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