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Good day yall,

I jus put on my Greddy Type RS BOV and realised that there is some problems with my boost. Apparently it onli boost up to 5 instead of the 7 on the stock boost gauge. And my engine stalls frequently nowadays.

I know many are sceptical bout BOVs and would most prob tell mi to pull it off and put back the stock but .... ;)

Anyone encountered the same problem before.

I have also purchased the following parts.

1. Profec B spec 2

2. Apexi pod

3. Hybrid intercooler

4. Power Fc

Gona put em all up when i have time and what kinda kws should i be expecting? Any tunners or mech to recommend to out em up? I am based in sdy.

Current ride is a r33 gtst.

Thanks

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1.) the stock boost gauge is not in PSI. it is in Inches of Mercury.

7 on that gauge is = about 15 psi.

2.) atmo venting bovs will cause your car to stall as it makes the car run rich in between gears or when ever it vents.

basically choking your car with fuel.

an R33 with full exhaust, pod, FMIC, POWER FC tuned to run say about 10-12 psi will probably get 200rwkw.. give or take 10rwkw depending on tune, dyno, your fuel pump and ability to flow enough fuel.

if you have stock clutch, it will now start to slip.

if you have stock fuel pump, you are playing with fire.

if you have no cold air intake and shield or box for the pod, you're being silly

if you have standard plugs gapped at the standard 1.1mm, you will now have missfire problems and will require new plugs with a gap of about 0.8 or 0.7

You are based in Sydney so there are many many places to go to have it all done.

depends on how many monies you have.

CRD, Unigroup, just get a car mag and pick a tuner.

with 200 odd rwkw, maybe you should also look at handling mods.

$2K gets you a whiteline WORKS kit.

then maybe you should get good brake pads.

possibly some decent quality tyres.

there you go.

money all gone

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Hmmm.. but wat causes the boost to stop at 5 then ?

And as for the fuel pump. What would be a possible upgrade to it?

CAI. where can i get one of these.

Questions may sound stupid but i jus started to think of increasing the performance of my car therefore know nuts bout it.

And yes... its already sucking all my monies..

But can't wait to put all of em up...

Thanks

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mine did the same thing when i installed the atmo bov( no probs with stalling though), cant remember what i did to fix the boost, however if your cars stalling try using the HKS Electronic Idling Stabilizer (negun sell it for $150)

discription: (ripped from nengun)

The HKS EIDS has been developed to buffer dramatic airflow meter signal fluctuations. By buffering these fluctuations the EIDS prevents engine stalling or stumbling associated with sudden imbalances in air/fuel ratio of airflow meter-equipped vehicles that utilize atmosphere venting blow-off valves.

Edited by RyanN
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if you don't already have a boost controller, then 5 on the factory gauge is about what you should be seeing.

5 on that gauge is about 9 psi I think.

which is what the R33's have on the second stage.

they are 7 psi until a certain revs or something.

Fuel pump upgrade would a Walbro pump. 255L/min... supposed to supply enough fuel for up to about 500hp or something.

CAI = Cold air intake. you can make one up for yourself using that flexy air con ducting tube. or you can use plumbers Drain pipes..

or I'm sure some shops will sell you an extremely expensive one that pretty much does the same thing.

basically something that can direct air from where your factory side mounted intercooler was, up to your pod filter.

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GTST, can u try and help me on this 1

ive just put in a fmic, 3inch twin dump and frount pipe, hi flow cat, goin into a 3inch cat back zorst, pod filter, standard bov (works fine) electronic boost controler and ive gappd my plugs down to 0.8 and even on low boost the car does this crazy thing afta 4900rpm, sounds like its hittin an invisable rev limiter, feels very bad

and at high boost even under the revs still mis fires and dosnt wanna drive

im stummpd

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Cerci - People love to say "mate this has been covered many times so do a search" and then you do and you get a whole bunch of posts with people in there saying "mate this has been covered many times so do a search.

so I won't.

even though you should.

Boosted RB25det and misfire over 5000rpm go hand in hand.

However, there are a couple of reasons that could be causing it.

I'll list the common ones.

1.) spark plug gap is stock at 1.1mm and the increase in boost is blowing out the spark.

2.) spark plugs are old and possibly damaged with a hair line crack.

3.) running rich and retarded

4.) faulty coils.

5.) afm meter cut

rule them out one by one and you will solve it.

1.) gap them to 0.8mm (already done it)

2.) replace them with new NGK copper plugs at right gap and right range.. or maybe one range cooler.

3.) need some sort of fuel trim adjustability.. SAFC is the cheapest option.. POWER FC is the best option.

4.) cheap way to possibly help issue is to tape them up.. might help..

see here for details.

http://www.skylinesaustralia.com/forums/in...2356&hl=misfire

5.) not sure how to test this.. but I think the AFM cut is much more harsh then a missfire so I think you'd be able to tell if you get a cut rom the AFM.. it almost dies for a moment rather than hesitate like the misfire does.

now hopefully when someone goes, I've got a misfire/flat spot at 5000rpm region, someone else will go, do a search mate, they will and find this.

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as for the miss it should only happen at light throtle position high revs, that should be the coils, and or gap. I have just got my split fire coil packs putting themm on tonight (see if miss and hesatation is gone)

Oh as for Atmo blowoff i have an apaxi duel chamber and have no probs, but the remapped ECU prob helps so after your PFC and tune all should be well

Edited by race_snooze
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Yeh with the atmo blow off valve if you have the correct atmo then you should be sweet. A freind of mine has a GFB stealth BOV specially designed for r33 skylines and with blow off valve itself can be tuned to allow enough air to go back into the engine while still being able to release some air into the atmosphere for the sound. You can also just buy a gfb hybrid and also turbosmart has the dual port. they are more expensive but it saves you from having to purchase a SAFC or Power fc to control air flow.

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if you don't already have a boost controller, then 5 on the factory gauge is about what you should be seeing.

5 on that gauge is about 9 psi I think.

which is what the R33's have on the second stage.

they are 7 psi until a certain revs or something.

Fuel pump upgrade would a Walbro pump. 255L/min... supposed to supply enough fuel for up to about 500hp or something.

CAI = Cold air intake. you can make one up for yourself using that flexy air con ducting tube. or you can use plumbers Drain pipes..

or I'm sure some shops will sell you an extremely expensive one that pretty much does the same thing.

basically something that can direct air from where your factory side mounted intercooler was, up to your pod filter.

Tks guys.

Just got my car back yes from nathan at annadale. Looks good now. Great work from nathan.

Would be looking at a new set of tyres now. Currently running on compliancing tyres. Freaking NS1s. Am looking at falken rt215. Where can i find em in sdy at a good price?

Any reviews on this tyre? Idid a search and there were mixed reviews. Got me confused.

ANy othre tyres to recommend? Basically am buliding the car for daily driving and occassional track days.

Tks for the replies in advance.

Jay

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