I hear people talking about being at 9 psi and changing it to 12 psi before a race. Im pretty knew to the hole thing so sorry for the stupid questions, but how do you do this? Do you need a boost controller or somthing? And is it bad for your car to do it? I read some where that you shouldnt go over 10 psi with out some good engine mods. I'm about to order a HRC Stage II turbo for my 98 eclipse, the site says it should run around 9 psi. Is that pretty good, or could I change it after I get it to run better/faster? Again sorry for the dumb questions... =/

- Thanks in advance

Try to know the workings of a turbo before you even attempt to put a kit in your car. As far as raising the boost, yes, you need a boost controller. If the wastegate spring is at 9 psi, you can't go lower than 9 even if you set it with a boost controller. I'm pretty sure with the intercooler, there's gonna be some type of pressure drop, so even if the spring is rated at 9 psi, you probably won't see 9 psi in the boost gauge (if all you have is a spring).

Thanks, Im trying to read as much as I can about how they work and all in the in's and outs of them before I get it, so at least I'll be able to understand whats going on in there.

And you said if all as I had was a spring? Im guessing thats all Im going to have?...

hey man... your in the turbo gruop buy right. i'm too. i was wondering about this question too about changing psi and the what not.
i'm trying to learn as much as i can about this turbo thing, i'm going through the turbo archives for a couple of days now.

Yeah, like said, you need some sort of boost controller, two main types, either manual, or electronic. Basically how it works is that it "fools" the wastgate spring. The wastegate is what controlls how much boost you can build. Its a little metal flapper inside the turbo that re-directs exaust gases so that is doesnt spool the turbin wheel as much. The wastegate flapper is controlled by the actuator, which is spring loaded. Some springs are set to 5 psi the other HRC one is at 9 psi. So what a boost controller does is that it limits the amount of boost pressure the wastegate spring sees. So take me for example, i'm running around 9 psi right now. I have the stage 1 spring at 5 psi in my actuator. My manual boost controller is hooked inline with the vac/boost line that goes from the turbo to the wastegate, and it sees 9 psi going into it, but only 5 psi gets out of it, and maxes out the wastegate spring, keeping the pressure steady. Hopefully this makes sense...

Yeah thanks it helps, and for the most part it made sence, Im trying to learn as much as I can w/o having to ask too many dumb questions, I can hopefully find some one else that asked the question before me so that I dont have ask =)

So any more info you think I should know please feal free to post it

- Thanks again for the info

One more question, I know that if you have higher psi it will put more stress on your engine. Your saying that the boost controller "Fools" the wastegate into thinking you have more psi, so by doing this are you affecting your engine life at all? Like if you really have 9 psi, and had the boost controller to change it to 12, would that eventually catch up and ruin somthing?

>Yeah thanks it helps, and for the most part it made sence,
>Im trying to learn as much as I can w/o having to ask too
>many dumb questions, I can hopefully find some one else that
>asked the question before me so that I dont have ask =)
>
>So any more info you think I should know please feal free to
>post it
>
>- Thanks again for the info
>
>One more question, I know that if you have higher psi it
>will put more stress on your engine. Your saying that the
>boost controller "Fools" the wastegate into thinking you
>have more psi, so by doing this are you affecting your
>engine life at all? Like if you really have 9 psi, and had
>the boost controller to change it to 12, would that
>eventually catch up and ruin somthing?


HRC doesnt recomend to go over 300HP on a stock motor. I would say with the HRC kit, 10 PSI would be *safe* limit, assuming PROPER tuning and fuel delivery, and a motor that is in very good condition, with good compression. Every kit comes with a boost gauge that reads how much boost pressure is at the intake manifold, its the same pressure that is entering the boost controller, or if no boost controller, directly at the wastegate actuator. Running more boost does put more stress on the motor, and eventually a rebuild will most likely be needed, BUT, if properly tuned, it should last a long time at a good 8-10 psi. Its VERY important, esp when running higher boost, that you keep a close eye on your gauges. You *should* go buy and EGT gauge(exaust gas temp) and an Air/Fuel ratio gauge to tell you how you engine is responding to boost. I wouldnt' even think twice about boosting without these gauges. Learn how to use them, and tune by them, as this will save your motor from a pre-mature death. Our engines are pretty well built stock, and if in good shape, and proper tune, 10 psi shouldn't be out of the question really. I strongly suggest to go through the turbo fourm here, and just go back into the archrive threads. You will be astounded as to how much you can learn right away, its how i did. There is enough info here to keep you glued to your screen for days on end...

with hrc stage 2 turbo kits dont go over 9psi and you should be 'pretty safe'.. also change your oil more often, make sure timing, and fuel are within specs of hrc and you should be cool also.. i would do alot of readings on turbo to give you a idea of whats up.. to let you know it took me about 2yrs till i got my turbo kit.. and guess what i know alot about it all now, but not everything... try to find some local 2gnt buds near u or someone who knows how engines work etc... oh yah do a compression check before puttin a turbo on...
happy bostin..:D


Michael 99gs
HRC Stage 2
Stage 3 process begins anyone got a 420a block thats not spun etc?

http://www.dreamwater.net/purplebeast

Thanks for all the info, few more questions if you dont mind.
Ive searched around to find out what size injectors I should get and got out of it I should get around 315cc, but what is s-afc that every one talks about? Also was reading up on what kind of oil to use, I live in FL so its pretty hot down here, so 10W-40 should work for me?

It also seems that every one with the HRC Stage II setup is running at 5 psi... It says on the page it runs at 9, so does it come stock at 5? And you can put it safely up to 9? And im guessing I would need the boost controller to do that.. right?

- Thanks again for your time and help

>Thanks for all the info, few more questions if you dont
>mind.
>Ive searched around to find out what size injectors I should
>get and got out of it I should get around 315cc, but what is
>s-afc that every one talks about? Also was reading up on
>what kind of oil to use, I live in FL so its pretty hot down
>here, so 10W-40 should work for me?
>
>It also seems that every one with the HRC Stage II setup is
>running at 5 psi... It says on the page it runs at 9, so
>does it come stock at 5? And you can put it safely up to 9?
>And im guessing I would need the boost controller to do
>that.. right?
>
>- Thanks again for your time and help


You can run stock injectors, you just have to run more fuel pressure under boost, that sprays the extra needed fuel for the extra air getting in there. I just upgraded to 315 cc injects to be safe, and for lower fuel pressures. I use Mobile 1 Tri-synth 10-W30(green cap). The HRC stage 1 kit comes with no intercooler,and is set to run at 5 psi, no more, no less. The stage 2 kit has an intercooler, and a 9 psi spring to run 8 psi, no less. You have about a 1 psi of pressure drop from the side mount intercooler, so it runs about 8 psi. You dont need any boost controller at all with these kits, only if you want to go past 5 psi on the stage 1 kit, and if you want to go past 8 psi on the stage 2 kit. DONT run more than 5 psi without an intercooler..bad for the engine..

Thanks again, but what was the s-afc ? And I plan on getting the front mount intercooler... so that means no psi loss ?

Sup Kin, see you found the groupbuy. As for the S-afc. It is an air/fuel controller. You can lean or richen out your car by adjusting it. You can do this in different increments up through the rpm range to better tune your car and make sure you are not running too rich or lean. Like what was said, look in the archives. I spent about a week learning what things do and i still feel that i could have a better understanding. Good luck and happy boostin. :thumbsup

Thanks a bunch