R32 GTSt Leaning Out

[OLi747]

hey there.

i seem to have a problem with my r32 gtst. engine mods are as follows: 3" turbo back exhaust, turbosmart bov, K&N pod. now heres my situation. when i put the bov on the cap that is suppose to cover the plumb back didnt fit so i left it as is open into the atmosphere. a couple of weeks later i put it on the dyno and it showed that it was leaning out. is this open pipe the cause? it made 125rwkw (i cant remember the revs). is this a low figure for such a car or am i just expecting too much? im also thinking about boosting, what is the max boost the stock turbo will handle while still operating at good effiency? also how much power can i expect from this?

thanks in advance

OLi

[predator]

If its your return pipe, probably yes..

If its not, probably no..

Just get something the right diameter, and use a hoseclamp to squeeze it on there.

[OLi747]

yeah ive blocked it up and it goes noticably better .. the dyno operator said it might be the airflow meter or the fuel pump .. ill post up the dyno sheet when i get a chance ..

[«Cyph3r»]

bov i don't think should make it lean out, when my sisters 32 was leaning out it was the afm.

[BHDave]

Ive seen the stock bovs start to vent at higher pressures when they are disconnected but not blocked. This would cause a rich, rather than lean stuation.

as predator said, if your return pipe is open then that would cause problems as it will suck air in after the afm.

[TTT]

so you left the return pipe open right?

a coke bottle cap or similar fits over it.

then use a hose clamp to clamp it on there.

did you get a lean dyno read out "AFTER" you blocked this hole?

125rwkw is about normal for a r32 with exhaust and pod.

I'm sure that if the return pipe is blocked and you went on the dyno, you will find a nice rich figure.

[OLi747]

nah didnt dyno it after .. the hole is now blocked and it does go a little bit better.. next time its oin the dyno ill pay particular attention to the a/f ratio

[TTT]

well think about it.

when the hole was open, it was sucking in air which wasn't measured by the afm.

the air that the afm measures, gets the right amount of fuel.

the afm goes.. "HEY ECU... I got x amount of air commin in to the engine.. Make sure you add the right amount of fuel"

the ecu goes "yeh yeh.. I got ya covered"

and there is peace on the planet "combustion chamber"

but then you go "I'll just leave this hole open... she'll be right mate"

so all this extra air sneaks in to the combustion chamber where the air and fuel mix and get exploded by the sparks..

but due to more air in there that the afm didn't know about, you have a lean reading..

this is all true.

if you listen carefully, this is the conversation that goes on in your engine bay.

ocasionally, you might even hear the afm go "nah *** ya.. I'm not playing today.. I can't be farked"

then the ecu gets upset and the car runs like shit..

true story

I like stories!!

[MattSR]

Amen!

[OLi747]

haha thanks for the help mate the storey was great! hole has been blocked good and proper!

[TimmyC]

hmm i think 125rwkw is a tad low for a 32gtst with a catback and pod.

[Z00MxRACING]

hmm i think 125rwkw is a tad low for a 32gtst with a catback and pod.

yeh i got 135.7 rwkw with pod, full exhaust only ...

now i have bigger turbo, fmic, avcr to 1.0bar, apexi custom air intake / pod, and when boost kicks in hard ... it feels like dat my afm or pump is leaning out ... and sometimes the engine cuts out ... sounds like fuel cut ??? coz i dont have a fuel cut defender.

would an power fc solve my issues??

[jazza08]

Ye.. ive seen 140rwkw outta an air filter and zorst. So your reading is fairly low!

Your fuel pump should be able to handle 135rwkw and so should your afm however the fuel pump being old may of had it??

A power FC solves most issues

[Z00MxRACING]

so whats the max power i can have b4 i have to start changing the fuel pump / afm ??

i was told around 170rwkw my injectors will max out ??

will power fc fix this ?? or do i have to get a 550cc or higher items?

[jazza08]

With a fuel pressure regulator you maybe able to tickle 180ish rwkw

GTR inecjtors go straight into rb20s (444cc), once tuned with the power fc and a bigger fuel pump then its just a matter of turbo choice and boost levels to determine power levels

Oh and grab a z32 afm as an rb20 afm will max out around the same time as the injectors, might as well replace both at the same time rather than going back for another tune to put the other one on later!