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Hi all,

this has prolly been discussed a squillion times, but...............

what is the 'definitive' stock standard boost on a R33 series 1 (late 95 model)

GTS-t. This weekend I installed a Speco Boost guage and GFB Boost Ctrl.

Easiest fitment I have ever done in a car, ever. I installed Speco first so I could find the current PSI, (regardless if reading was right

or wrong, it would show me the exact difference between new boost and original setting). It showed 6psi, then after install went to 10 psi (1.75 turns).

Boost now comes in alot sooner (which I like) and comes on less 'linearly' (I also like).

Only issue was that the car 'popped' 2 or 3 times from the exhaust at around 3500 to 4000 rpm then is OK. This only seemed to happen when I really 'gave it to her', otherwise, all is teriffic. I wound down the controller by .25 of a turn, now indicating 9 psi, but 'popping' is very rare. (but still there if you really kick it).

Am I running too much boost? (Even if my Speco is wrong, I estimate a 3PSI boost regardless of actuall, by way of comparison).

I honestly thought that these

things

can handle 12psi, relatively well (?)

Is there any subsequent mods I should also perform after boost increase (although very small) to the car.

I do love what the GFB control has done, it feels faster, without going to far over the top. I am an 60 to

80 kmh driver, but like getting there quick.

Thanks, and please, I would like 'experienced comments on this one. (hate to sound like this, but hey, we're talking 'boost' here!!!

Mark

Your car is missfiring. No big problem. I had the same problem. 1st thing to do is check your spark plugs and change them if need be, that should fix it if not it could be your coil packs (not in many cases). Get your car on a dyno if its other things they can tell you from that. My problem ended up being that my Air Flow meter was maxed out only on 10psi so it can be a variety of thing. If you want to read more do a search for "missfiring" and read till you are content.

Your car is missfiring. No big problem. I had the same problem. 1st thing to do is check your spark plugs and change them if need be, that should fix it if not it could be your coil packs (not in many cases). Get your car on a dyno if its other things they can tell you from that. My problem ended up being that my Air Flow meter was maxed out only on 10psi so it can be a variety of thing. If you want to read more do a search for "missfiring" and read till you are content.

Hi Croat,

car was tuned by Genesis last week, with new plugs $26.50 each and AFM cleaned out aswell. Car was running perfect, so from what ur saying, extra boost changes the 'tune' or finds dodgey parts in your car. If I pulled the boost contoller out , will this miss-firing be gone?

Also Croat, you seem pretty certain on Missfiring, true, it does feel a lot like when I hit the rev limiter at 7000, but are you sure it may not be the sound of 'over-boosting'. This would really scare me!! Does an 'over boost' sound, sound like a 'rev-limiter' sound? Or when you over-boost is the only way to tell ........ is when your motor instantly blows up?

Just would love to know what noises are made when certain things are happening or about to happen. ...Croat......anyone..

I will check that 'content' as you suggested. thanx.

new plugs needed dude...

Thankyou very much, but sorry RB25, I just can't go with that. They're new and have been installed by 'the experts'.. (as per my thread).

I will come back to that if all else fails, or more ppl's back you up with the same.

Thanx RB25,

Mark

New doesn't mean good, I've bought dud plugs before.

Buy one extra one and start changing one at a time, only take you six days of going to work and back to test them all.

Or whip 'em out and get 'em tested at 10psi, good auto sparkies can do this.

regap the plugs to 0.8mm they are probably 1.1mm

Evan

ok.........so I take it that I'm not actually destroying my car by driving it at a displayed 9psi, and I hear popping from the exhaust? (occasionally when gunning it?) this is my MAIN CONCERN.

What's the principle (your theory) of reducing the spark gap?

I've rung my mechanic who did my plugs, he used Nissan Platinum plugs gapped at standard 1.1mm, I suppose, to be fair, I should take the plugs out and gap to .8mm (as he does on boosted cars). He did the plugs before I did the boost thing...so I shall do that (?)

So, even with a light boost, re-gapping is very important???

Thanx everyone, this truely is a grand site!!

Love an ansa to dis!!

if they are gapped at 1.1mm

then they can handle standard boost fine. I currently have Iridiums gapped at 1.1mm and running standard boost. No misfire etc Also did dyno recently, everything is perfect.

But i imagine that at 10psi etc u will definately need to change the gap

when running more boost the plugs definately need to be regapped in my experience, however i have heard it is hard to regap iridiums without breaking the tip.

I wouldnt use them as they are expensive and if the plugs arnt right it is a costly excercise to change, perfect for a stock car if you want them to last 100,000km, but if you start fiddling they are a waste of time and money in my opinion.

Evan

exactly what this bloke is saying. Im running 9-10psi and i regapped my plugs to 0.8.

Coppers all the way mate!! heaps cheaper than iridiums and with my car i need new sparkies no matter what brand at abotu 6000klms anyway so its no use forking the extra 80 for me.

Apparently the coating is meant to come off like someone said tho if u regap iridiums.

thankyou to all those above for your input. Looks like Croat and RB25 are on the money, Thanx for all the subsequant back up from other members.

One last Q on this one.....Do the standard Nissan Platinum plugs have one only electrode, so are they easy to gap to .8mm. Anything to keep in mind?

Ta again.

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