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View Full Version : Help with bg gt-x jdm-spec ecu boost limit


Vipe
27-11-2006, 04:18 AM
Hi, again everybody...

I always come here when I have problems... :(
I have driving with my gt-x transplant 323f a while. In summer I upgraded exhaust to 2.5" from gt original pipe. I also have cone filter.

When I use gears bigger than 3 with full acceleration and rpms are something over 4000 car makes "fuel cut". I usually have almost 1bar boost when it cuts (about 14-15psi).

I know that 2 gtx bgs have here used hks fuel cut defencer. I already ordered one but can anyone help me with connections? I think it just comes between some line to ecu? I can't ask from those gtx owners because it was on car mag...

You might suggest ecu upgrading because people have 2 opinions about fdcs.
But that is not what I asked :)

Thanks!

project.r.racing
27-11-2006, 08:35 AM
with original computer the fuel cut is set normally at the 14-15psi where you suggested it is happening. with a car with the air-flow meter, once it registers too much load, it sends a signal to the ecu, and it cuts the fuel to protect the engine to lower the revs.

the fuel cut defender suppresses these signals, allow you to run more boost into the original engine.

you would install the fuel cut defender in-line between the AFM and ECU. which wire that is, i do not know. hopefully someone else might know?

you can install the fuel cut defender - have done heaps on other cars. but on a standard gtx set-up. the turbo doesn't make much more power over 11psi. and the cut is higher than that. so i don't see the point to it.

a new aftermarket ecu will allow you to turn all parts of engine and gain alot of extra power between 8.5-11psi and will not have fuel cut using map sensor instead if wanted that way.

ryan

Dogo
27-11-2006, 09:17 AM
the fuel cut defender is nota good idea with the standard ECU. It only has data up to 1 bar ( 14psi ) , so trying to push it past that will lean out the mix and damage your engine.

The standard turbo will probably break soon after 14psi too.

upgrade your turbo and the ecu if you want to push more power out. You can get quite a lot of improvement without raising the boost just with custom fuel maps,
But you should also strengthen the engine internals because they're not designed to handle such high pressure.

Vipe
29-11-2006, 07:11 AM
Thanks for advice, I will try to figure out connections when fcd arrives.
I also think that it is between ecu and afm.

My goal is to use gtx with that bigger exhaust and filter, without changing ecu at this point. If boost gets too high with fcd, I will try something else. Maybe port wastegate?

If someone knowledge about fuel cut defencer connection, I will appreciate help.

rab
19-12-2006, 03:34 PM
can you tell me which HKS FCD you are using, product number
or a link to the exact one you are getting would be great.
i was told that are cars don't have a FCD that will work?
thanks ryan