Jump to content
SAU Community

Recommended Posts

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.

P19-11-10_18181.jpg

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

Sorry for the crap video

Link to comment
https://www.sau.com.au/forums/topic/344858-r33-94-gtst-nolow-boost-help/
Share on other sites

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

post-2054-1290248508_thumb.jpg

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

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.

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?

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

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Hi, is the HKS  Tower Bar still available ? negotiable ? 🤔
    • From there, it is really just test and assemble. Plug the adapter cables from the unit into the back of the screen, then the other side to the car harness. Don't forget all the other plugs too! Run the cables behind the unit and screw it back into place (4 screws) and you should now have 3 cables to run from the top screen to the android unit. I ran them along the DS of the other AV units in the gap between their backets and the console, and used some corrugated tubing on the sharp edges of the bracket so the wires were safe. Plug the centre console and lower screen in temporarily and turn the car to ACC, the AV should fire up as normal. Hold the back button for 3 sec and Android should appear on the top screen. You need to set the input to Aux for audio (more on that later). I put the unit under the AC duct in the centre console, with the wifi antenna on top of the AC duct near the shifter, the bluetooth antenna on the AC duct under the centre console The GPS unit on top of the DS to AC duct; they all seem to work OK there are are out of the way. Neat cable routing is a pain. For the drive recorder I mounted it near the rear view mirror and run the cable in the headlining, across the a pillar and then down the inside of the a pillar seal to the DS lower dash. From there it goes across and to one USB input for the unit. The second USB input is attached to the ECUtec OBD dongle and the 3rd goes to the USB bulkhead connected I added in the centre console. This is how the centre console looks "tidied" up Note I didn't install the provided speaker, didn't use the 2.5mm IPod in line or the piggyback loom for the Ipod or change any DIP switches; they seem to only be required if you need to use the Ipod input rather than the AUX input. That's it, install done, I'll follow up with a separate post on how the unit works, but in summary it retains all factory functions and inputs (so I still use my phone to the car for calls), reverse still works like factory etc.
    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
×
×
  • Create New...