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How to say Bye Bye to Auto Boost Cut

Nizmo

By Nizmo,
in Engines & Forced Induction

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Nizmo Grand Master

Nizmo

Posted
Posted

Anybody know? Currently my Auto is boost cutting at 12psi :D Which is ruining my fun.

Ive been told the only way to get rid of a boost cut in an auto is to get an aftermarket ECU but that doesnt sound entirely right to me and i know someone .... somewhere must know how to get rid of it!!

Please Help!

Lauren

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https://www.sau.com.au/forums/topic/38535-how-to-say-bye-bye-to-auto-boost-cut/
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gatty Mentor

gatty

Posted
Posted

Offtopic: you can have a BOV on a auto correct?

sorry, i see you have a auto and was wondering this the otherday - my mate is going to buy a aut 33 and asked me and i had no idea...i assume you can fit one but they are not needed like on a manual?

Also, I think a ECU upgrade will fix the cuts :)

paulr33 Grand Master

paulr33

Posted
Posted

the bov vents pressure that is deflected off the throttle body when you close the throttle (aka lift your foot off the pedal).

This action still occurs on an auto and the pressure has to go somewhere so it still has a bov. i think some people believe a bov is manual only and it goes pschhh when you release the clutch but it doesnt, its when you release the throttle. Should be the same stock bov wether manual or auto.

A lot of vl turbo's are autos and they don't have bov's...

What do they sound like? Compressor surge sound (the flutter noise). If they had a factory bov or aftermarkent one you'd get the pschhh

paulr33 Grand Master

paulr33

Posted
Posted

the only option i know of is get someone to modify the ecu itself (chipped) or get an aftermarket ecu. you probably wouldn't want to run more than 12psi on the stock ecu anyway the fuel maps and ignition timing probably won't be able to match it and you'll just get fuel cuts or other timing wierd stuff from the ecu limiting stuff.

Nizmo Grand Master

Nizmo

Posted
  • Author
Posted

cars boost was set at 12psi ..... but it only hit boost cut when it was cold ....so no point putting FMIC in til this is sorted me thinks.

Workshop not to eager to up boost anyway from 12psi until FMIC because engine is pinging.

Geoff ...... agh dont run high boost on restrictive exhaust .... ive already made that mistake LOL and bleed valves are useless .... get an EBC ;) My 2c :O

rev210 Grand Master

rev210

Posted
Posted

Niz,

I thought you were sick of spending money on broken things?

I say this because the factory turbo will break sooner rather than later if you run it above 12psi. This is regardless of the FMIC. Also the turbo is capable of it's best performance under 13psi imho. (I say this with several low 13's under my belt with a smidge over 10psi on the old gtst).

The boost @ 12psi and the standard intercooler ought not prevent you running a mid 13 pass. I think the best plan of attack is to optimise what you have already before shelling out more money.

Go without the boost cut and put that money on an adjustable exhaust cam gear (same price roughly) we can then get the mid range torque up a bit and improve the boost characteristics.

cheers

Dave

Nizmo Grand Master

Nizmo

Posted
  • Author
Posted

i know this is a ressurection but i have an exhaust cam gear :D I only found out yesterday ...... paul put his GReddy one on my car and never told me - they havent played with it tho. ;)

rev210 Grand Master

rev210

Posted
Posted

Niz,

last time paul put one of those on his he didn't get any extra power :D (just having a dig), might pay to ask if it is in the factory position with 0 adjustment or whether it has been set to anything else. The base timing needs re-adjustment with the cam gear timing change and you might require a little fiddle with the S-afc too but, its very easy to set it up for some extra zing if he hasn't had a chance to muck around with it yet.

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