A friend notcie that i was only at 3.5 boost at 4k and i was wondering when would i hit full boost on an s4 turbo? My car stock only have emmissons removed

 

It depends on how hard you depress the accelerator. Are you talking about being at WOT? We need specifics.

 

Yes i mean at WOT and i was doing a pull and shifted at 4500rmp and my friend said i didnt go pass 3.5 psi

 

Shift at the redline fool.

if you were in a high gear it'd spool up slower I'd assume dunno why your shifting at 4,500 doing a wot pull.

 

hahaha i dont haha to redline to beat the honda around here but i'll give the redline a go but i thought u hit max boost at a lower rpm then a higher one

 

I've never even driven a turbo'd car lol but as far as I understand car's hit boost more towards the redline.

The turbo spools up by the exhaust pressure, at low rpm's you'll have less exhaust output then at a higher rpm The quicker the exhaust can escape and spool up the turbo, the quicker you hit full boost.

I believe rx7's start spooling at 2.5-3k rpm or so

 

i can hit full boost by 3600 rpms, i have full exhaust though and running 13psi

 

is everything else stock?

 

yea you should be hitting more boost than that assuming your exhaust isnt clogged or something. My s5 stock turbo hit 6lbs(wastegate) by 26-700.

 

Exhuast isnt clogged just had it off cleaned and replace the main cat with straight pipe

 

Are you sure the boost gauge your using is accurate? Do you have any exhaust leaks?

 

sounds like you may have a boost leak. A stock turbo can hit 6 or 7 pounds by like 3000rpm

 

i do have a exhuast leak im just waiting for it to stop raining to fix it but i'll post what happens after

 

well there are exhaust leaks but there are also boost leaks. That means bad gaskets, poorly fitting vacuum hose, poorly seated intercooler piping, loose clamps, etc. that makes a difference man. You really need to pressurize your intake to check for leaks. I highly recommend a tool similar to this: www.boostpro.net/prodtester.html . use it with a reducer to connect to your turbo inlet.