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hey guys. just got a couple of questions, iv done as much googling as i can but have failed miserably.

im buying a catch can off justjap, and need to know whether i want the ones with 15mm outlet, or 9mm outlet. i am running a s2 rb25det!

unrelated 2nd question..

on my intake pipe, there is a little pipe for plumbing back your blowoff valve. atm its not plumbed back so that hole is open. now, im running a vipec ecu which means theres no afm present, which means that extra air coming in there shouldnt really be a problem, but i realise its not going to be filtered.. so i should probably either block that hole up, or plumb back my bov, correct!?

3rd edit noob question! my cars been tuned to 10 and 14psi, if i asked my tuner to change the 14psi to 16psi, would it require a retune? or could he just tap the boost up a bit with no retune? its vipec built in boostcontrol!

noob question 4. should i gap my sparkplugs to .8mm now its running and tuned @14psi ?

thanks for your time!

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hey guys. just got a couple of questions, iv done as much googling as i can but have failed miserably.

im buying a catch can off justjap, and need to know whether i want the ones with 15mm outlet, or 9mm outlet. i am running a s2 rb25det!

vernier calipers are your friend.

on my intake pipe, there is a little pipe for plumbing back your blowoff valve. atm its not plumbed back so that hole is open. now, im running a vipec ecu which means theres no afm present, which means that extra air coming in there shouldnt really be a problem, but i realise its not going to be filtered.. so i should probably either block that hole up, or plumb back my bov, correct!?

yes. block it up.

Yes that is the size you want.

If you're not using that hole in ur intake i would definitely be saying to block it up. Besides you can probably hear a weird noise coming from it as well as the thought of unfiltered air entering ur engine.

No a retune should not be required as he should have already input higher than 14psi to begin with for this exact reason as well as boost spiking etc etc. Imagine a line of best fit curve of your boost compared to your afr's already. He should have been able to input what the afr's for that boost would be without actually having to be at that boost especially since it's only 2psi more.

Always best to ask the tuner as he is the one that would know what he's set etc.

Yeah pete, I'd say they'll be 15mm as 9mm is a bit small for breather hoses.

Block the hole, or plumb the BOV in. I would suggest plumbing it in as it's going to be the first thing a cop sees when they open the bonnet (your atmospheric BOV).

Do you know what spark plug gap you are running at the moment? I'm pretty sure the standard gap is 0.8mm There's nothing wrong with a larger gap unless you are having problems with it misfiring underboost. If so, gap them down a bit. You shouldn't have to go below 0.8mm at this boost level. If you have platinums I wouldn't try gapping them.

P.S how'd you go with the tyres.

thx for all the help guys :)

hey luke :)

im not sure about the plugs, but i read somewhere that the plugs i use came at 1.1mm to start with.. ? and that anything over roughly 10ish psi u should start bringing them down.. il do some more reading :)

sorting out tyres today, just need some fken free time

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