R33 94 Gtst No/low Boost... Help

[skeg_man]

Hey Guys,

I've been searching High and Low for the answer to my question..... Why don't I have any boost, even spooling until over 4000rpm or more?

I'm very new to turbo's and i've only had the car for around 2 weeks. One of my mates came for a drive with me (him being in previous skylines before) and said It just didn't have the same kick back as previous ones. Then I picked up my car after getting a front and rear wheel alignment, and the fella asked if I was running the car with minimum boost? or none at all? He said It didn't feel like any of the other ones he has been in!?!?

The car has a pod filter and after market intercooler installed. Along with yellow jacket coil packs.

My questions are,

Should it have some boost even when cruising? in all gears?

Should the first stage kick in or around 2500rpm in most gears?

Should I just buy a boost tap (Manual or electric)?

Does anyone have any other ideas on what and where I should start to look? I'll post up a video of my driving it, viewing the stock gauge. Also I'll post up a picture of the vacuum hose setup near the boost solenoid (think thats the name). The red hose goes into the charcoal filter? is that right?

Cheers in advance peoples.

http://s49.photobucket.com/albums/f296/ske...-11-10_1810.mp4

Sorry for the crap video

[paulr33]

the stock guage on the dash (turbo icon inside RPM tacho) should swing past 0 mmhg on the guage (which is half way) after about 2 seconds of accelearting

anything past 0 is "boost" it should goto around 3/4 which is around 0.75kgcm2is after 4500rpm and before that it should be around 0.5kgcm2 if its a manual gtst

the stock guage is in MMHG but its close to kgcm2 so its ok as a base measure

[paulr33]

ok so the guage is in MMHG

-7 is vacuum

0 is basically absoute pressure

+7 is 760mmhg which is 1 bar or 1kgcm2

when you drive it will be around -500 ish

when you floor it, it will build pressure to 0 (all cars do this, even N/A)

then it will go past zero and start building boost pressure

3/4 up the guage is +5 or +500mmhg which is around 11psi ish

the green area is vacuum

blue line is around stage 1 boost - 0rpm to 4500rpm approx 5psi on manual GTST

pink line is around stage 2 booost - 4500rpm to redline, approx 7psi on manual GTST

the auto runs approx 5psi on stage 2 boost

[Rowdyr32]

I fixed a R33 for a guy a while ago were the line to the map sensor was cracked after Autobarn put a boost guage on it. He thought the turbo was blown but it was the car not sensing boost so it wouldn't boost up. Check the map sensor line for cracks! It effects the ecu and boost gauge.

[skeg_man]

It was/is some sort of vacuum leak. Where ever the stock gauge line is. I installed a DEFI boost gauge today, and there we have it. Positive boost. It shows no issues at all. Spool time might be a little out but not very much. There is def. positive boost. As far as I can tell, the boost is a smooth process, so I kinda didn't notice it.

Does anyone know where abouts the line is to check for the stock boost gauge?

[paulr33]

its just behind the firewall, where the steering column goes

its a little light brown box with a single vac line into it and 3 wire plug

it might be disconnected, therefore it never goes boost and will always sit around -600 ish on the stock dash

[Power Glide GTR]

can you here the turbo spooling up at all?

i have seen the flap inside exhaust housing snap off which wont close so it wont boost up