R34 GTT Turbo Upgrade - Direct Bolt On (almost)

[GTSBoy]

Despite what Tao says, the OP6 highflow will indeed run only 10 psi if you really need it to. Mine is doing that right now (well, actually, it's doing nothing right now because my pinion bearing sounds like a broken end mill) because I haven't got a dyno (it also broke) to do the necessary after upgrading AFM and injectors. So I'm just pedalling it around on low boost right now. It is fine. I do suspect that it is in the wrong part of the comp map and making hot air and can only hope that it all gets a lot better once I can push it up to 18 psi or so. I suspect this because it pings like a motherf**ker if I turn it up to ~12 psi. Hence I suspect that it is hot. (I also have suspicions about my fuel pump going soft at the top end, for which I would also really like the dyno to be back in action!!).

Anyway, point being, you could put a highflow on without tuning it. Not ideal (for a completely stock tune) because it would be bitchingly rich and retarded. Mine was tuned to provide about 190 rwkW on the stock turbo at 12ish psi, so it's perfectly safe so long as I don't let it ping. It did so for a little bit immediately after I put the car back together until I realised why the check engine light was coming on! (Like, on the first drive!). Running it on the dyno would have been better, perhaps.

In case it is not obvious, I only have the low pressure actuator on this turbo and will want to swap it for a 14 psi or so one when I can.

[silviaz]

14 hours ago, GTSBoy said:

Despite what Tao says, the OP6 highflow will indeed run only 10 psi if you really need it to. Mine is doing that right now (well, actually, it's doing nothing right now because my pinion bearing sounds like a broken end mill) because I haven't got a dyno (it also broke) to do the necessary after upgrading AFM and injectors. So I'm just pedalling it around on low boost right now. It is fine. I do suspect that it is in the wrong part of the comp map and making hot air and can only hope that it all gets a lot better once I can push it up to 18 psi or so. I suspect this because it pings like a motherf**ker if I turn it up to ~12 psi. Hence I suspect that it is hot. (I also have suspicions about my fuel pump going soft at the top end, for which I would also really like the dyno to be back in action!!).

Anyway, point being, you could put a highflow on without tuning it. Not ideal (for a completely stock tune) because it would be bitchingly rich and retarded. Mine was tuned to provide about 190 rwkW on the stock turbo at 12ish psi, so it's perfectly safe so long as I don't let it ping. It did so for a little bit immediately after I put the car back together until I realised why the check engine light was coming on! (Like, on the first drive!). Running it on the dyno would have been better, perhaps.

In case it is not obvious, I only have the low pressure actuator on this turbo and will want to swap it for a 14 psi or so one when I can.

Yup, from my understanding, every time I install a mod such as injectors, turbo, intake plenum, it needs a tune updated every time unless I put all the parts on at once and do 1 tune then. I've got an aftermarket ecu and has been tuned already but as you mentioned the highflow would need a tune. 

What is that ping that you're referring to, do you mean detonation and if so, does it make the same sound as when a knock sensor goes faulty and makes a "ping" type of sound? I used to have that sound on my other car until after I finally replaced the sensor after years lol.

[GTSBoy]

Pinging is detonation, yes. It sounds like a bunch of angry little men with hammers beating away on the inside of the engine.

Pinging doesn't happen just because the knock sensor dies though. All that will happen in that circumstance is that if the engine does ping (and it shouldn't) then it will keep pinging because the ECU can't hear it. My check engine light was coming on because that's what the ECU does when (amongst other things, of course) it hears too much pinging and tosses all its toys out of the crib.