2 1JZ boost questions.

timothyphicks02

New Member
Nov 13, 2007
24
0
0
39
florida
Im new to 1jz's. I myself dont have one Im asking for a friend. I was wondering what the stock psi is set at for the twins and what the max psi is about? I tried searching and got a few threads not exactly telling the stock and max psi. I even tried google and wikipedia. I found 18-22 psi is the max and even then there are reliability issues. So please if you could tell me stock twins psi and there max psi thatd be great.
 

suprahero

naughty by nature
Staff member
Aug 26, 2005
14,971
0
36
53
Roll Tide
You're probably not going to get a max psi on the twins because nobody knows how strong your friends car is or how well his turbo's are running. I never ran my twins so I don't know what the stock boost is.
 

timothyphicks02

New Member
Nov 13, 2007
24
0
0
39
florida
Thanks foreverpsycotic.

and yeah I understand your point suprahero I mean if the engine is stock and good condition. just a ball park stock psi and a reliable max. if you want to factor in age and wear over the years if possable... but just looking for a rough figure for a good stock engine.
 

foreverpsycotic

Back in the game!
Jul 16, 2006
3,171
12
38
37
ATL
Personally, I would do a 3" turbo back exhaust and call it done. You should see around 14psi with a 3" downpipe, cat and exhaust, and you will see another 1-2psi with a test pipe.
 

kanji1jz

kanji
Jan 16, 2008
103
0
0
tampa fl
Mine run around 13-15 with a 3" turbo back exhaust and 2.75" intercooler piping and a huge front mount (probably more than I need but whatever) intercooler. I have heard of some running 18 psi consistently and others that crap out at 15-17. Pretty much if he wants to raise his boost he needs to do it with the understanding that he might have to replace/ rebuild soon.