sr losing boost

[FcMURRRDA]

so i just swapped my s14 sr20 and i already set the boost controller to 15psi (ecu was tuned for 15 so im leaving it that way) it makes boost but right when it makes 15 it drops all the way to 9-10 psi (around 5-5500 rpms it drops in every single gear) it has vacum (-16/-17) i have a AEM tru boost controller. im sure iv set everything right on it but idk im stumped.. PLEASE HELP!

[FcMURRRDA]

If know one knows the problem.. does anyone knoe any good socal shops that could help me out?

[gretz]

If its the stock s14 turbo, it may not be able to make 15lbs past the RPMs you listed...

Most of the smaller t28 and t25 turbos wont hold 15lbs to redline

[cotbu]

Let's breakdown your issue, I don't know your setup, but something is wrong if it takes 5000rpm to make 15psi from a T series turbo!

So you need to specify what you have (cams), and also your vacuum routing and a video and describe how you are actually testing this. (2500rpm cruise) then (Full throttle pull to 7000rpm).etc if you are using 50% throttle then you're just spooling too slow and your test results are normal.

[FcMURRRDA]

Originally Posted by cotbu

Let's breakdown your issue, I don't know your setup, but something is wrong if it takes 5000rpm to make 15psi from a T series turbo!

So you need to specify what you have (cams), and also your vacuum routing and a video and describe how you are actually testing this. (2500rpm cruise) then (Full throttle pull to 7000rpm).etc if you are using 50% throttle then you're just spooling too slow and your test results are normal.

Ok I will make it a video today hopefully. But its a stock s14 Sr with s15 turbo (its the turbo that came off the automatic s15's not the ball bearing one) 550 injectors, stock cams, fmic, straight exhaust and a turbo header. It makes full boost from 4k to 5k but after that the boost drops to 10 psi and it stops pulling and it starts back firing and running rich so I never tried redlining it cause I'm sure ill blow it up if I tried. Do you think I might of set the boost controller wrong? It's a tru boost AEM

[Frankyy]

what about your intakes? if you have the original rubber intake and removed the wire inside, the rubber intake will collapse on itself at about 5k RPM and you will loose boost.

keep driving the car and if if starts out at 5500 and the hotter it gets it does it at lower RPM it's your spark plugs since it's most likely a street tune it's not 100% perfect

16-17 vac is a little low for a completely stock sr it should be around the 19-20 mark also

[FcMURRRDA]

Originally Posted by Frankyy

what about your intakes? if you have the original rubber intake and removed the wire inside, the rubber intake will collapse on itself at about 5k RPM and you will loose boost.

keep driving the car and if if starts out at 5500 and the hotter it gets it does it at lower RPM it's your spark plugs since it's most likely a street tune it's not 100% perfect

16-17 vac is a little low for a completely stock sr it should be around the 19-20 mark also

Yea there's no wire -__- and its super soft. I'll check the timing also and see wats up. Where can I buy the wire?

[godsmack]

Do you have the stock actuator? I'll bet the actuator is going bad. Either that or like frankyy said the stock intake will collapse also. Or the boost controller is bad.

[blksylv]

surprised noone has said timing yet. i had the same issue when i tried setting the timing on my redtop and it ended up retarding itself about 8 degrees. car would hardly make boost and vac was around 17

[blessedhellrider]

V-takkkkkkkkkk!

[ultimateirving]

hey man, does sound like rubber intake collapsing too.

[cotbu]

Replace it with an aluminum or aftermarket intake pipe. You might be able to find a used oem intake, but why?