Speed Cut And Boost Cut

[WogsRus]

I know. before you say it, i have used the search.

What i need to know is if i cut sire #53 on the ecu, however i have heard that this disables your HICAS. Since i like HICAS how else can i remove it, or will cutting the #53 output fix this, Has anyone done this? If so does it work.

ALSO how do i remove the Boost cut and how does the boost cut work. I was going to get one off these, Gizzmo FCD,

http://www.nzperformance.co.nz/store/view_...hp?product=GFCD

But i have no idea where to get one here in OZ. Are these worth it, and do they work well.

How does the boost cut work and when does it come on or how is it determined by the ECU that it needs to be on.

OK thanks. This is a bit urgent, i need to get the car ready for track in two weeks.

[WogsRus]

anybody?

[Haysey]

i got an aftermarket chip for my car that removed the speed cut and also did some other good things, im not too sure on the boost cut, wat car is it btw?

[WogsRus]

I forgot to mention that it is a 95 R33 GTST.

I have a friend who is a wiz with electronics, so he can make something for me, just not sure how the boost and speed cut work?

Can somone clarify how the speed and boost cuts wort on a R33?

[Wink]

Boost cut is the wrong term for it, as the 'cut' has nothing whatsoever to do with boost/pressure levels.

The right term is "Rich and Retard" - do searching in the forum on this term instead of "boost cut" and you may find better, more technical answers, especially from Sydneykid.

Basically when you turn up the boost on the RB25DET, your fuel/air mixtures will be very rich at the top end (down to AFR of 8-9). The ECU will then retard the engine as a reaction to overly rich fuel/air mixtures.

[WogsRus]

SOOO, how do i fix that, a SAFCII would suffice to lean out the mixture.

Thanks BTW will search.

[satanic]

The new Turbosmart FCD works a charm so I've heard; perhaps call them up and get some more details on it.

The Speed Cut can be removed by simply cutting the wire; look up the ECU pinout manual to find out which one.

[WogsRus]

Forgot to mention though, has anyone done anything to do with the speed cut, ie: cut the wire to the sensor, i should do it and find out. LOL.

[CSNet]

Apparently cutting "wire 53" works. So I have read.

[WogsRus]

does it have any affect to Hicas?

I like mine and prefer to keep it.

[CSNet]

No idea sorry mate. I just remember seeing a few threads over the past year or so about removing the speed limiter. My search couldn't find any results

[WogsRus]

same boat, i've heard aboutit, read on a whole heap of sites to cut the wire, but nothign to do with hicas.

Thanks anyway.

So will having a SAFCII fix the boost cut if the mixtures are fixed.

[Wink]

Get a PowerFC instead of a SAFC2.

PowerFC will let you do lots more and you'll get more from tuning that than you will a SAFC2.

Also, do not cut the speed cut wire if you have an auto.

[WogsRus]

only problem is i have no money for a PFC, but enough left to get a SAFC II, plus sometimes these come up cheep.

UPPPSS i better tell my mate not to cut the wire, he was goign to do it, but has an auto.

Thanks mate.

Either way, would using a SAFC II to lean out the mixture, fix the boost cut retard?

[mad082]

a mate of mine cut a speed wire (don't know which 1) and it got rid of his speed cut.

as for rich and retard, a safc won't get rid of it. it has nothing to do with air/fuel mixtures. it is to do with the amount of air passing through the airflow meter at any given rpm. it isn't just when you get to a certain pressure it cuts out. the amount of airflow might be ok for 4000rpm, but its too much at 3000rpm, so the ecu kills the engine for a second to slow the turbo down. then the engine will kick back in and continue on as if nothing has happened. you don't lose power after it has happened, just for the time that it kills the motor. when mine would do it it would proceed to light the tyres up down the road when it kicked back in if i was in first or second gear.

[mad082]

i would also have to suggest the new turbosmart fcd over any of the others i have seen, as it has a set of instructions just for skylines.

but ultimately a full ecu, or a remapped ecu would be better. i picked up a remapped r33 ecu for $200. it was remapped in japan. it has no speed cut, higher rev limiter and no airflow protection.

[WogsRus]

So the cut, feels like a missfire then, or what? The car will be in Tassie on Monday, and as soon as it comes in, it's getting a new IC, new exhaust, boost regulator, fuel pump. I am planing on running 10-12psi on the stock turbo for now.

What are my chances of incountering boost cut, and is there an easy way to get rid of it.?????????????????

[WogsRus]

SO where do i get the remaped ECus form?

ANYONE GOT ONE for sale?