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ok i have just brought a r33 series 2 gtst after seling my series 1 gts and it was stock when i got it since i have installed a gfb bov, hdi duel stage boost controller, new radiator platium plugs and splitfire coils and turbo back 3inc.

ok with the boost controller i have low set at 8 and high at 12 now the problem is it make boost fine but in 1st gear nothing it will only hit a max of 2psi like wtf every other gear fine no prob just 1st gear wont boost and i didnt drive it enough before i modded it to notice if it boosted stock so is it a saftey thing with the ecu or something else could u all please give some insight

thanks pottsy

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lol lay the welcome mat out why don't ya, but i must confess that i do agree.

although that said he should be making more boost.

id say poor install of boost controller. in higher gears/load, its probably hiding it a bit.

You seem new, and even though you've bought average to crap mods, I'll go easy on you.

Turbos don't boost in 1st gear. The car doesn't have enough load.

Seems like an odd claim; Factory R34 turbo I'll happily hit the limit of the R32 10psi actuator in 1st gear?

I am very well mechanically minded just not with turbos mafia wat mods would u have done I only want 200kw the only other thing I was goin to do was to do was fmic already upgraded to r34 smic but getting fm nd a tune just factory ecu still but I have just done timing belts nd all seals and gaskets in engine and taken photos at every step so I could put up a guide if u would all like ?

mech minded or not, your boost controller install IMO is the issue.

either that or the controller itself.

'dual stage' bleed values, which is what you have, are well know to be very average products at best.

there are better, and incidentally cheaper, options.

Turbos don't boost in 1st gear. The car doesn't have enough load.

they build later in 1st but unless you have some massive turbo on it they'll almost always reach 90% of target boost in 1st. my old 25 had no trouble building 20psi from a gt30 in 1st even with wheelspin. a standard turbo will easily make 10-12psi in 1st by 4000-4500rpm with properly setup boost control

as nismoid said probs the boost controller. have you set it up so that it keeps the gate shut until 2-3psi below target boost? (no idea how the hdi works but it'll have some sort of adjustment)

Edited by JonnoHR31

my old 25 had no trouble building 20psi from a gt30 in 1st even with wheelspin. a standard turbo will easily make 10-12psi in 1st by 4000-4500rpm

20psi, in first gear with a GT30 on a RB25?

ok. Now I have seen it all.

Post a video or I call 110% bullshit.

20psi, in first gear with a GT30 on a RB25?

ok. Now I have seen it all.

Post a video or I call 110% bullshit.

cant do video, car isnt running and has a different combo now anyway. but it definately made more than 2psi, which your trying to say is normal with a standard turbo?

i have a r34 gtt with standard turbo, it will make max boost in first gear when it is set to low ( low setting is about 8 psi i think, definately more than 2 : P). i have a greddy profec B-spec II as my boost controller

..i believe my brothers 180sx has the same problem as OP though. reaches next to no boost in first..do u just need a good boost controller (installed and set correctly) to fix this problem?

My highflow rb20 turbo makes 13-14psi by redline in first on my rb25, the stock turbo easily makes the 10psi by redline, I have seen it many many times in my old rb20.

The issue here is your actuator but beed valves are generally crap and I recommend either using nothing as you'll get 10psi fairly easily off the spring with an rb20 actuator and a 3" exhaust, or get an electronic bleed valve. The fact you are making less boost than with nothing indicates your waste gate spring is probably not tensioned correctly or there is an issue with it, if you stuff up the install of a boost controller it usually results in infinite boost, not less than the spring boost.

Have you installed an rb20 actuator? If not look into it as your actuator is probably the issue here, did it do this before?

In my experience is the bleed valves just cause the boost to spike or don't do anything, on larger turbos they work better as they are slower to respond and easier to control.

i have a r34 gtt with standard turbo, it will make max boost in first gear when it is set to low ( low setting is about 8 psi i think, definately more than 2 : P). i have a greddy profec B-spec II as my boost controller

..i believe my brothers 180sx has the same problem as OP though. reaches next to no boost in first..do u just need a good boost controller (installed and set correctly) to fix this problem?

No you don't it shows there is an issue with something else, a bleed valve can only increase boost from the base spring pressure which should be at least 8psi, 10-12psi if using an rb20 actuator. If you are getting less than this, it indicates the actuator is opening too early for some reason, hence the slow boost build, having a controller on there just masks this. If you remove the controller it probably only makes 2psi in every gear, shows there is something definitely wrong.

Edited by Rolls

Yeah I also definitely make more than 2psi in first gear.

I thought a boost controller could only make more boost than what the actuator is set to, not less.

Either way you could try a turbotech boost tee as a test, they are excellent and only $30.

Boost is proportional to load really. As someone said go up a steep hill in first and you'll make more post then going down a steep hill in first.

On a straight road you should really reach a decent boost level, maybe a few psi short of set boost depending on what your running. I def hit 10psi on stock turbo in first and am able to do about the same with my new turbo which is only set to run 13ish psi ATM.

I had a dual stage on mine and it seemed to work fine right up until I installed the power fc boost kit. My dual stage was turbo smart and they did recommend that you remove the ball (and possibly the spring as well) in the t piece (where it splits to go wastegate one way and boost feed the other)

I did this and it seemed a bit better. I'm not sure if the HDI kits are the same. Is there anything like that in the instructions?

Boost is proportional to load really. As someone said go up a steep hill in first and you'll make more post then going down a steep hill in first.

On a straight road you should really reach a decent boost level, maybe a few psi short of set boost depending on what your running. I def hit 10psi on stock turbo in first and am able to do about the same with my new turbo which is only set to run 13ish psi ATM.

Yes, but the job of your actuator is to get the boost to remain steady as best it can. If it is working well it should sit on the same boost no matter what the gradient of the road or gear you are in (as long as it can get to the required boost level).

Yes but I was giving an example of how the turbo behaves respective of load. Not wether or not it will stay consistent if it reaches it's boost level. I felt it was a better example then saying you won't hit target boost in neutral (unless maybe your on limiter) as opposed to flat to the floor in third. The hill thing was just an easier comparison of load.

OP: read the manual to see if what I have said in my last post is in there and if it says the reason behind doing that mod. Might be for boost creep rather then your problem I forget. Otherwise I'd try putting stock parts bak on to trial (BOV and boost solenoid mainly) if it starts working then it will show you your problem

I could make a max of 5psi in first, nothing more. WIth a GT30 and 0.63 rear.

OP needs to look at if the wastegate is holding shut. Or put tension on it.

Wait... Something is wrong then, I think mine will even open gate on high boost in 1st gear! That's 26psi :)

Will test with some videos tonight and see what I actually get.

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