I'm running a Garret T3/T4 Hybrid turbo on my S5 short-block with everything else from an S4, including the switched out OMP/eccentric shaft cover, blah blah blah..



Anyways! I don't have a boost controller, but I've got a Racing Beat 3'' down-pipe, 3'' high-flow cat, 3'' Racing Beat Turbo-Back dual exhaust, Walboro 255, Vortech Fuel-Pressure Regulator, and RC Engineering Blue-Printed Balanced Injectors which I believe are basically just upgraded stock injectors (they still say DENSO on them).. Oh yeah, and my ECU has a fuel-cut defender that has been programmed into it already.



My question is, with the stock wastegate on that turbo, what do you think the boost will be at? I am scared because I have no boost controller, and I don't wanna blow the motor. With my core being S5, and everything else being S4 along with the mods I listed, what's the highest boost I can run SAFELY without lessening the life of the motor drastically?



Here's a pic of the bad boy while it was off the car during the whole motor-swapping process that my brother and I are almost finished with..

In my experience if you get .5 to .7 kilos of the actuator you will be lucky. I have had lots of problems with the boost falling off in high RPM's with the Hi flo turbines.



Since the turbine is S5 boost creep will not be a problem as are the S4 types. Are using a FMIC? If you are then your boost without a boost controller will be even lower due to the pressure drop. As far as maximum boost you can run most of the Hiflo's I have used wont do much more than1.2kilo or 16psi. Anything above that is just a waste of time. I am not sure what size your injectors are now but without some tuning you will need to run at least 680's in the secondaries for that much boost.



Good luck

My signature lists all my mods. The injectors are stock S4 Turbo II injectors that have been blue-printed and balanced by RC Engineering for fuel efficiently and better flow.

Uh, that looks like a compressor upgrade or hybrid to me.

So it can't be a T3/T4???



The stock wastegate is sprung for 6psi, so with creeping (most likely with your set-up) it should hit 10psi easy.





-Ted

T3 compressor housing T4 exhaust housing = hybrid



The stock wastegate is only allowing for 3 1/2 psi as I said, it's smoothe and doesn't leak at all. I need some type of boost controller to turn it up to 10psi though. :/

What you are seeing is a common thing with Hi flo turbines. I am not exactly sure why but they just don't seem to boost. Even if you get a boost controller the boost will fall off at high RPM. You can modify the actuator as I mentioned in the 2nd gen area earlier.



This is the "modifictation" that I just did on a S5 car with a High flo.

Huh?

No T4 comes internal wastegate.





-Ted

T4 exhuast with a T3 compressor...WTF?

OK OK so I don't know how the f*ck it is what it is! >_<



But what I do know is, the car is running a solid 4 psi, with no boost controller. It semes it should be higher, but the stock wastegate is very small, I don't know. I have to have my brother explain this **** to me since he drives an SR'd 240. I hardly even know what .70 AR on my turbo means! ;_;

If you're not running an Autometer boost gauge, it just means you have a nasty restriction somewhere - and that's not normal.



It's possible your high-flow cat is disintegrating.



You could be running too rich (why are you running that Vortech FPR?), and that can be surpressing boost.





-Ted

the FPR came with the car. Should I just disconenct it? What will that do to the REST of the car? Is it even possible? That might even explain my horrible idling, and hard time starting the car since it's not getting fuel, you think?

Maybe its getting too much fuel........ What is the pressure set at the the FPR?



It could be that your motor is old and worn out so there is not enough compression there to make decent boost. This would make it hard to start as well and if you have the fuel pressure cranked up it would all complicate.



I dunno but it still sounds like you need a boost controller but before you do anything else go buy some guages so you will know what is going on.

The core has about 40k original miles on it, everything else is from the old blown S4 motor, but I cleaned the throttle body by hand, myself, before I put it back in the car, and everything else was cleaned, and every gasket/seal was replaced EXCEPT for the injector seals, which didn't look like they needed to be replaced anyways. :/

We made a boost controller and we got it to run 12psi.



How much boost can I run safely with my setup on this turbo?



12psi was f*cking FAST!!! We're talking like a 13 flat 1/4 or HIGH 12. I was keeping RIGHT up with my brother in his monster 240.



But again, how much can I run S A F E L Y with my setup? I don't want to have it be fast but blow on me in a month. I need it to last at least 6 months so I can mod it a little and THEN sell it! lol...Seriously though!

With a normal computer and normal injectors I would say you are at the limits with 12 psi. NOrmally with a ROM tune and normal injectors in Japan we see 270hp at the wheels with a high flow. Larger injectors and good intercooler boosting 14.5 psi you can see 320 at the wheels.





Get some 720's for the secondaries and you will be straight for a while.

Yeah, but how much boost can you run on the stock seals?

More than that turbo will boost......



Boost is a relative term...... people should think in terms of CFM instead of boost. Most hi flo turbines wont make much power above 14-15psi........sounds alot like the stock turbine dosen't it?! However that larger more effecient compressor makes more power at the same boost levels........HMMMMMM Basically the turbine can only spin so fast before it gets out of its effcieancy range this comes down to about 450CFM on most hi flo turbines. If you turn up the boost the compressor chops the air more......heating it up and reduces the power potential.



You might see some small gains just from the rise in pressure but unless you have a serious intercooler and you ignition timing is set up for those super high intake air temps the engine will eventually die.



If I could have a turbine that 500hp at 10psi of boost then I would use it, unless it took it a day and a half to get to 10psi.

Well unfortunately, cooling is an issue considering my boost, because I'm running a stock intercooler and radiator. I don't drive it hard often though, so it's all good. On the highway though, I have no 4th gear, so cruising at like 4,000+ and THEN flooring it = bad, I've noticed.



If I had a front-mount intercooler and Koyo radiator, how much boost can I run though? Right now I'm using kind of a home-made boost controller and the most I can get out of it is about 12psi.



What is CFM and how is it measured?



My friend was running 14psi on his stock seals basically with a T3/T4 turbo and the other necessary fuel upgrades, but he had no cats and eventually blew a seal. I have a high-flow cat... O.o



Ugh! I'll never get a straight answer!

30+ if you have enough fuel and you can keep the intake temps cool enough for it not to detonate.



on a stock ecu and injectors 10-12 psi is about your limit.

You'll never get a straight answer cause you don't know how to describe what you're doing and trying to do.



Seriously, I dunno who you've been listening to, but stop listening to them!



We're trying to help you, but you're talking apples and we're talking oranges.



Bottom line, if you're stock ECU with stock fuel injectors, don't go over 12psi (stock turbo?).



If you really got a compressor upgrade, don't go past 10psi.



Why? Cause you're maxing out the fuel injector capacity with the stock ECU. I've seen my stock 4x550's hit 95% on my stock ECU at 14psi. I was running a very tiny compressor upgrade, and this set-up made 253 to the wheels on a DynoJet.



Stop ******* around and keep the boost down. If you need to keep it alive for a few months, why you trying to blow it up???





-Ted

CFM = Cubic Feet per Minute. This is the standard for detailing the amount of air being processed by a engine. Just like the old V8 gearheads when they talk about a 650holley......that is a 650CFM carburator. That means that carb will support enough fuel and air for 650CFM. After some experience and looking around you will see that 450-500 CFM will yeild around 350hp. More important than that is if you know that the stock turbine will flow 300cfm at 1kilo of boost and that the compressor upgrade will flow 450cfm 1kilo then you know the uprgrade flows more air.



More air requires more fuel to keep from running lean and blowing the motor. Your 4 550cc injectors lack the capacity to support more than 300hp. 300 is really pushing the envelope and using a stock computer does not even allow you to tap into those injectors real potential so therefore using a boost setting of 12psi as a refrence you should not boost more than 12 psi without running a risk of damaging your engine.



There are a number of reasons you can blow your motor........I am the master of blowing 13b's and have blown 6 engines in one year before.. from that I have learned that you can get by doing lots of stuff and the car will run good and be fast for a while, then one day when the temperature drops outside or humidity is just right or your fuel pump skips a beat or whatever.......... it will blow. Everyone on the forum will give you advice on the safe side of tuning aka too much fuel, conservative timing and low boost levels. You can use that advice as a guideline to build your own car and try stuff that narrows on the extreme but the more you try the more chance of damaging your engine and spending even more money to fix it. If you don't mind popping a motor or two on your learning curve then go ahead and play and learn, if not then follow along and build a respectably fast car that will last a long time.

or just blow the bastard and sell it to me! i love buying t2's that don't run. LOL i'm just playin though. i'm a pissy bitch cause i still have no ride. play it safe and you'll be plenty happy to save the money for more fun stuff than spending it on just getting it runing again.

I'll sell my RUNNING car for $6,000.



I'm about to buy a short-shifter for it too! ^_^