Optimum boost PSI...
Optimum boost PSI...
Turbocharged 13b motor with EFI. Stock rotors, moderate street-port. What PSI do you guys think this could safely run to still be durable?
I've been lookin at some high PSI turbos...
I've been lookin at some high PSI turbos...
There's too many variables to say. It depends on what turbo you're running, whether you have some sort of charge cooling, grade of fuel, port timing etc. It's something that's best determined on a dyno equipped with a wide-band o2 sensor and egt.
Nikki-Modder Rex-Rodder
Joined: Feb 2001
Posts: 2,890
Likes: 14
From: Trying to convince some clown not to put a Holley 600 on his 12a.
Yep- That's what they say! Right, 680? I mean everyone knows that 28 psi is the magic threshold number, right?
...Or are you just bragging.
Again.
Ya see, my problem here is not you. It's the fact that you have proven yourself very knowledgeable, yet seem to want more to let the board know (over and over) of your achievements more than helping people out by giving them useful information.
Now I could presume that "Unreality" does'nt have the means to boost his car up to 28 psi between now and the time that he inadvertantly happens across some more research data, but did you also presume as such?
Or would it be fine by you for someone to actually try cranking up their boost to 28 psi?
Think, man!
...Or are you just bragging.
Again.
Ya see, my problem here is not you. It's the fact that you have proven yourself very knowledgeable, yet seem to want more to let the board know (over and over) of your achievements more than helping people out by giving them useful information.
Now I could presume that "Unreality" does'nt have the means to boost his car up to 28 psi between now and the time that he inadvertantly happens across some more research data, but did you also presume as such?
Or would it be fine by you for someone to actually try cranking up their boost to 28 psi?
Think, man!
Jeez Guys, relax. I have seen 680 trying to help a few people here and there as well. There's nothing wrong with being enterprising either.
Back on topic. Try no more than stock boost levels for that particular year engine. I believe it's 7 PSI on the TII's and 10 on the 3rd Gens.
My tuner has told me that a good healthy engine can usually go to 15-17 PSI with a healthy tune and a good AFR.
Anything after 17PSI start looking for Race Gas and extremely good fuel and spark management.
Good Luck.
Back on topic. Try no more than stock boost levels for that particular year engine. I believe it's 7 PSI on the TII's and 10 on the 3rd Gens.
My tuner has told me that a good healthy engine can usually go to 15-17 PSI with a healthy tune and a good AFR.
Anything after 17PSI start looking for Race Gas and extremely good fuel and spark management.
Good Luck.
Nikki-Modder Rex-Rodder
Joined: Feb 2001
Posts: 2,890
Likes: 14
From: Trying to convince some clown not to put a Holley 600 on his 12a.
Originally posted by Directfreak
My tuner has told me that a good healthy engine can usually go to 15-17 PSI with a healthy tune and a good AFR.
Anything after 17PSI start looking for Race Gas and extremely good fuel and spark management.
My tuner has told me that a good healthy engine can usually go to 15-17 PSI with a healthy tune and a good AFR.
Anything after 17PSI start looking for Race Gas and extremely good fuel and spark management.
Sorry, Directfreak, but 680 could'nt just say that?
Robert and I on are great terms, exchanging Emails, ect.
This has nothing to do with previous clashes between him and me on this board. We've since made 'nice-nice'.
But I have told him about this before.
Trending Topics
Originally posted by Sterling
him and me on this board. We've since made 'nice-nice'.
him and me on this board. We've since made 'nice-nice'.
Just yankin' on ya Sterling. BTW, I have a Supercharger now. It's weird having over 100ft-lbs more torque than HP.
I guess I am a double agent know.
, You know as a Turbo / Super guy.
Nikki-Modder Rex-Rodder
Joined: Feb 2001
Posts: 2,890
Likes: 14
From: Trying to convince some clown not to put a Holley 600 on his 12a.
Originally posted by Directfreak
BTW, I have a Supercharger now. It's weird having over 100ft-lbs more torque than HP.
BTW, I have a Supercharger now. It's weird having over 100ft-lbs more torque than HP.
"Ooooooowhhhaaaaaaaa...Papa like?
Nikki-Modder Rex-Rodder
Joined: Feb 2001
Posts: 2,890
Likes: 14
From: Trying to convince some clown not to put a Holley 600 on his 12a.
While we're on the 680 topic, here's where I lost my cool earlier today... maybe I went a little too far, quite unusual for me
https://www.rx7club.com/forum/showth...hreadid=159427
https://www.rx7club.com/forum/showth...hreadid=159427
ill give it to him.. 720 out of a 12a is impressive.. but.. i agree.. too much bragging.. but then, if MY 12a made that much all my posts would say is
"720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! "
all good though.. when i see bragging, i just skip down to the next post..
to the topic of this.. i have nothing to say.. because i dont know.. but yea, if you take a stock motor, and boost up to 28 psi.. BAM... bad advise 680
"720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! 720! "
all good though.. when i see bragging, i just skip down to the next post..
to the topic of this.. i have nothing to say.. because i dont know.. but yea, if you take a stock motor, and boost up to 28 psi.. BAM... bad advise 680
I just read about the new Mitsu Evo coming out - the thing has 19 frikkin' psi from the factory and has a driver controlled water injector in the hugenormous air/air intercooler for low speed/high load (read:autocross) applications...
Re: ...and BTW.....
Originally posted by Sterling
Here's yet another brag by 680
Here's yet another brag by 680
yah, here is the dyno run,,, racing this weekend @IDRC
www.rotaryshack.com/movies
mexico 720
exhaust as too much for the mic. ..... sorry
720 @28psi i love to brag!!!!!!STERLING
i still love ya!!!
The optimum boost ..... is always 2psi more than you are currently running 
Seriously though, optimum for what? power.... the more you can the better; reliablity.... 0 psi; stock ports.... depends on tunning fuel, and even then there is a good amount of randomness, but I suppose a built rotor still has the same issues.
Like DF said, running stock boost is where you'll find a happy medium of relablity and power. If you want more, get a boost controller, and only turn it on when you need to.

Seriously though, optimum for what? power.... the more you can the better; reliablity.... 0 psi; stock ports.... depends on tunning fuel, and even then there is a good amount of randomness, but I suppose a built rotor still has the same issues.
Like DF said, running stock boost is where you'll find a happy medium of relablity and power. If you want more, get a boost controller, and only turn it on when you need to.
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