[FRAKK's2.5]

Hey Boys and Girls, I'm building my own turbo setup I already the stock WRX turbo and intercooler, I know I have to get a fuel preassure regulator (I hear the Vortec works well also I hear that you can rig one up really easialy) I need a fuel pump stock WRX or Walbro (don't know yet) the uppipe and downpipe I already have a hook up for it, does this sound complete to you guys? I'm going for big boost not yet anyway, prolly looking for about 3.5 or 4 maybe 5 but that will be pushing it.

Here are my questions:

- What sort of management do you recomend in order for my daily commuter to run good?
- Would the Borla headers be able to handle the Preassure of the turbo (yes I know I would have to get some sort of brackets)?
- How much boost can I run before I start to worry about my stock internals and how much boost can run realibly with considerable gains on the car?

Thanks guys

Frank


Long live the GC8

 

[Graham]

You will be a very happy man after this project is over. This type of setup is by far the best there is.

I think the Borla headers are up to the job, I don't know why they wouldn't be. I believe they are a bit thinner is thickness, but I don't see that as any reason not to "handle the pressure of a turbo".

If you can, skip the Vortech RRFPR. Yah, they're the the cheapest, but I have found mine is kind of flaky sometimes. For instance, I couldn't get it to raise fuel pressure until I had the vaccum line going to it so short that there was nowhere to mount it. I would try to get a Cartech unit if I were you.

Fuel pump? Well, its all about how much boost you want to run down the road. The WRX unit will work great for probably about up to 5 or 6 psi, then something like the super high flowing Walbro 255 LPH will work much better. Then again, the Walbro is also three times as much as a used stock WRX pump. Both will drop right in.

If not a fully programmable engine management system, then at LEAST a J&S Knock Sensor. The J&S is the absolute minimum you can have to protect your engine from knock, and a very good one at that. On my car with 4 psi (I have a J&S) on a Legacy RHB5 (almost same size as yours) I see zero knock, and have never heard it either. Its always good to have the J&S just in case though. This should be plenty for such low boost.

Max boost? I am preparing to take my car to 8 psi. But, this is with a newly added Link Plus system. I can really tune the car for a turbo now, allowing me to take it to its limits. With the WRX turbo, I would say about 8 or 9 psi is the max, though with someone really good tuning the car, 12 psi plus is probably do-able. Without the Link, I would not have taken my car past 6 psi though.


What are you doing for up and down pipes?


Graham

 

[5252]

good post, g man!

 

[10th Warrior]

correct me if i'm wrong, but, at least on MY00-01, doesn't the MAP need to be hotwired or some such shit so that it won't flip shit when there is positive manifold pressure?

anyway, if you're only running a few pounds of boost, i don't think you'd need to change the fuel pump. then again, its better to have too much fuel then too little

J&S for sure. other then that, the stock ECU should handle the low boost.

other things to think about would be a wastegate/boost controller. also, a boost gauge would be a good idea. a guy here had a shite wastegate that kept allowing the boost to creap up and spike on occasion. its good to have an actual measure of boost rather then assume the wastegate is functinning properly. a BOV wouldn't hurt either, though for only a few psi, its not going to be necessary.

as for boost levels, you really don't need much with the EJ25. the RS-T in stl, even when he was at 4psi of boost, could spank a WRX at any speed. remember, the ej25 has a high CR. it means you don't need alot of boost to produce alot of torque anyway, the guy ended up keeping it around 7 psi. the car was quite fast. then again. he did go through 2 water pumps (warrenttied!) and his headgasket let go. basically, that, or the tranny, is probably going to be the weak links, not the pistons and valves.

 

[FRAKK's2.5]

Graham and Jeff thanks for all the useful information. I have been calling around to all the Dealerships, trying to find out if I can get a Stock WRX fuel pump, but they are all well about the $250 mark that's well above what I'm looking to spend, however I have found the Walbro fuel pump for about $110 I think this will be my choice for now I have to get the Oil lines and I think I'm going to change my SPark plugs and wires next weekend at least to try to beef everything that I can this way everything that has an iinpact on the performance of the car can be up to par anyway thanks for all the useful info guys....

 

[Graham]

Used WRX fuel pumps are going for as low as $30 over on i-club and other places. Changing your spark plug wires in not completely necessary. The RS uses pretty stuff as far as spark goes. Plugs aren't necessary either. I ran mine on 4 psi for 9 months, no problems.


Graham

 

[FRAKK's2.5]

Hey thanks Graham, but here is yet another question, Would the stock WRX Injectors work on the RS? I hear people say that they will work good since these are Coming from a Turbo application and therefore giving more fuel when needed, also I have heard that these would not work since the injectors are coming from a 2.0 litter engine and would not be able to provide as much fuel to our 2.5 Does that make sence to you? Thanks for all your help man, you have been really helpful.

PS I'm sure I will have more question in as time progresses, since I'm still trying to figure out how the Fuck I'm going to make all this shit work.

Frank

 

[Boy]

The WRX injectors will drop right in to a MY99 fuel rail... I don't think they fit on the 00+.

 

[FRAKK's2.5]

The WRX injectors will drop right in to a MY99 fuel rail... I don't think they fit on the 00+.

Cool thanks man!

 

[Graham]

Bill beat me to it. Yah the injectors will work, just as he said. So, your best bet if your car isn't a 1999 is to find an intake manifold from one, and just use that (this is what I am doing) in conjunction with the WRX injectors.

There is no reason to compare injectors to the liter of an engine, they simply have nothing to do with eachother. The stock WRX injectors flow @ 420cc, and the stock RS injectors flow @ 280cc. So, obviously the WRX injectors give you a lot more room to tune (especially if you want to turn up the boost).

Right now, at 4 psi, my stock RS injectors are hitting 95% duty cycle, which means they are in the range of being so maxed they are ready to just stick open because they can't flow enough fuel. I'm hoping for somewhere around 85% duty cyle with 8 psi on the WRX injectors.


Graham

 

[10th Warrior]

I don't think they fit on the 00+.

yeah, they changed some of the damn emmissions plumbing in MY00-01 which basically means they won't take any other injectors, unless they were specifically designed for it.

 

[FRAKK's2.5]

Just recieved my Walbro Fuel pump! :biggest: I'm so sicked, this puts me one more step closer to the Turbo setup, now this is what's next:

-New Clutch
-Gauges Oil Preassure, Fuel preassure, Exhaust Temp gauge (Do you think I really need this?) Boost gauge.
-S-AFC (looking into Apex'i)
-BOV any WRX aftermarket BOV should work right?
-Oil Lines, to cool the turbo
-Any suggestions on a good Piggy back ECU?

I also might've already purchased some used JDM STi brakes pads with the Lines, looking for some front DBA rotors

I think I have the Boost greedyness disease now I'm aiming for 5 to 6 psi what else do you guys think I need for this setup?

Thanks

 

[10th Warrior]

Exhaust Temp gauge (Do you think I really need this?)

this will allow an indirect measure of A/F ratio, especially if its way lean. this will really help with tuning the AFC.

JDM STi brakes pads

won't you need the STi calipers for these to work?

 

[Boy]

Frakk, check out the E-Manage... screw the S-AFC. You need timing control, with a RRFPR and a Walbro pump your fuel system is set (shoot, you'll probably need to pull fuel). Oh, and yes, you need an EGT gauge, get much over 1600F and you'll melt.

 

[FRAKK's2.5]

won't you need the STi calipers for these to work?

Dunno man? would I? I just figured they would work, but I guess I was wrong..

 

[Tall J]

- What sort of management do you recomend in order for my daily commuter to run good?

Get your OEM computer flashed and re-mapped. Remember the guy with that sick-ass WRB WRX at Life Plaza? They have a 4 wheel dyno and all that jazz, that’s the your ticket to kick it for sure. The sight is weak but it gives the number and street address.

http://www.gtmotorsports.com/

 

[FRAKK's2.5]

Re: Re: building my own turbo kit...I need help guys

Get your OEM computer flashed and re-mapped. Remember the guy with that sick-ass WRB WRX at Life Plaza? They have a 4 wheel dyno and all that jazz, that’s the your ticket to kick it for sure. The sight is weak but it gives the number and street address.

http://www.gtmotorsports.com/

Yeah, that's cool and everything, but I don't think reflashing an RS ECU and programming it with the WRX settings will work after all we are talking about a Stock Turbo Engine (WRX) and a Non Turbo one going into aftermarket forced induction (RS)

Would this work on an RS? I don't think it would to be quite honest but then again what do I know...

 

[10th Warrior]

Dunno man? would I? I just figured they would work, but I guess I was wrong..

the pads have to be different shapes since the STi has more calipers. you might be able to shoehorn them in though. then again, brakes are one thing i don't want to have any lack of confidence in.

 

[Lo0mis]

Just recieved my Walbro Fuel pump! :biggest: I'm so sicked, this puts me one more step closer to the Turbo setup, now this is what's next:

-New Clutch
-Gauges Oil Preassure, Fuel preassure, Exhaust Temp gauge (Do you think I really need this?) Boost gauge.
-S-AFC (looking into Apex'i)
-BOV any WRX aftermarket BOV should work right?
-Oil Lines, to cool the turbo
-Any suggestions on a good Piggy back ECU?

I also might've already purchased some used JDM STi brakes pads with the Lines, looking for some front DBA rotors

I think I have the Boost greedyness disease now I'm aiming for 5 to 6 psi what else do you guys think I need for this setup?

Thanks

You'll also need coolant lines to the turbo. Are you getting a high-flow cat? If so which one?

And you may want to look into doing some sort of parallel fuel rail thing. I'm planning on eventually doing something like this http://www.rs25.com/Forums/showthread.php?s=&threadid=2126&perpage=15&highlight=fuel rail mod&pagenumber=3

 

[FRAKK's2.5]

You'll also need coolant lines to the turbo. Are you getting a high-flow cat? If so which one?

And you may want to look into doing some sort of parallel fuel rail thing. I'm planning on eventually doing something like this http://www.rs25.com/Forums/showthread.php?s=&threadid=2126&perpage=15&highlight=fuel rail mod&pagenumber=3

no plans on getting a high flow cat yet, a lot of people that I know are running fine with the stock cat, I haven't really thought of one yet.