Unfortunately the stock reg doesn't. It raises fuel pressure on loss of vaccuum for sure, but a different reg called a 'rising rate' reg is needed to increase fuel pressure in the boost zone. It will allow you to run smaller injectors, or another way to look at it is for mild boost you can install one and run stock injectors. You are moving beyond that though.
I forgot to mention I have an adjustable fuel pressure reg set at 55psi so that could help my scenario! I haven't thought about it for quite a while.
Just get bigger injectors and be done with it IMHO. No messing with adjustable FPR's or rising rate FPR's.
I first tried the adjustable Holley FPR and it worked for awhile but soon destroyed the diaphragm. Every time you take off that plenum for service it costs money for new gaskets. After the 2nd time I said enough and went from 24lbs injectors to 30lbs injectors on a stock FPR. Next time I'm going to 42lbs injectors and more boost.
Just get bigger injectors and be done with it IMHO. No messing with adjustable FPR's or rising rate FPR's.
I first tried the adjustable Holley FPR and it worked for awhile but soon destroyed the diaphragm. Every time you take off that plenum for service it costs money for new gaskets. After the 2nd time I said enough and went from 24lbs injectors to 30lbs injectors on a stock FPR. Next time I'm going to 42lbs injectors and more boost.
If your base fuel pressue is 43psi and you run 12psi of boost all of a sudden you have 12psi pushing back on the fuel in the injector, so your effective fuel pressure would be 43psi-12psi = 31psi @ the injector. If your just putting larger injectors to compensate for the loss of effective fuel pressure in boost then you'll bee PIG rich out of boost. Likewise If you just tried to raise your base fuel pressure then you'll have too much pressure at the injector anytime your out of boost and wind up rich again. You COULD tune around this within reason to get your idle back but part throttle is probably going to suffer with the limited tuning available to OBD-1 cars. A VERY simple fix is a rising rate fuel pressure regulator. which will raise the base fuel pressure in the rail 1:1 as you apply boost. So your effective fuel pressure stays the same. (43psi + 12psi -12psi = 43psi )
The effective pressure @ the injector greatly affects flow as well, most injectors are rated @43.5psi so for exampe if you are running 43psi in the rail & 12 PSI of boost your effectively running 31psi at full boost. If you use This Calculator you'll see that your 30LB injectors and been reduced to 25lb injectors
What size waste gate do you guys recommend for my boost range? (~10psi)
I have a Precision 38mm wastegate dumping into a 3" downpipe at 10psi it holds steady without rising at wot. Also I'm still using my stock fuel pump and #19 injectors on my cammed 3.4pr with meth injection. Not sure if larger injectors or fuel pump is needed or will help my application but the car is fast as hell as it is.
[This message has been edited by JCircs (edited 06-27-2013).]
I have an 86GT 2.8 turbo and run about 10 lbs boost with forged 9.2 piston, crane cam, custom intake and headers + other goodies. As for intercoolers, I think they're must have. An air to air setup done right will work fine. Since you can weld, I strongly suggest you make a set custom headers for it. With a turbo there's not much to be gained by building a complicated set with equal length pipes; a simple but good design will suffice. Think about it; it's kind of nuts to feed a turbo with those God-awful stock headers and Y pipe. BTW: I have an MR2 blow-off and a shortened MR2 intercooler the fan for which does double duty as it also cools the turbine. Good luck with your project.
Just get bigger injectors and be done with it IMHO. No messing with adjustable FPR's or rising rate FPR's.
Say what? You must raise the fuel pressure in relation to the amount of boost you are running. No ifs, ands or buts about it.
Also, as Francis pointed out, ditch the stock exhaust manifolds. If it were me, I'd run a set of cast iron manifolds from other gm 60deg V6's. They will retain heat better and wont crack as easily as the stock tubular manifolds.
[This message has been edited by BV MotorSports (edited 06-28-2013).]
There is a lot of info on here. Some I agree with, some I don't. For example, I don't think that the custom header route will gain you anything. The restriction in the exhaust is the turbo! Don't go too big on the exhaust pre turbo...from what I've read 1.5" for each side is about ideal for the spool/performance balance. Post turbo, go crazy with the 4" elliptical if you want. You probably don't need more than a 2.5" exhaust. Do re-weld/port the stock exhaust manifolds to prevent cracking and improve the stock restrictions.
Having 30lb injectors does not mean you will be running rich off boost. You just have to do a bit of tuning. Seriously where do you get that idea from?? Some MASSIVE injectors have trouble with low pulsewidths at idle, but not in that range that I've heard of. More like 60lbers.
No, you absolutely don't need a rising rate fpr. It just makes it easier to use smaller injectors.
Don't be scared off. You can do a simple system or a really complex system. It's a choice, not a necessity.
An intercooler will provide you with increased power potential and increased detonation margain. But, only if it's effective. It's been shown that it's very difficult to mount an effective air to air on the rear end of a Fiero. I had an idea to put on in a custo molded wing on the decklid, but after tuning out the 12psi boost I have, I see no real reason to go to that complex a solution. I think that the water/meth system has a good niche here, but it would be nice to not have something that runs oout (I like low maintenance rides!).
Originally posted by BV MotorSports: Say what? You must raise the fuel pressure in relation to the amount of boost you are running. No ifs, ands or buts about it.
You don't, really. The stock fuel pressure regulator already runs 35ish in vacuum and 45ish once vacuum is removed and you are into boost. Tuning with fuel pressure is considered to be the amateurs method. Don't take my word. Ask any tuner.
Then ask yourself, how many OEM cars with a turbo or supercharger use a rising rate fuel pressure regulator?
[This message has been edited by Hudini (edited 06-28-2013).]
Yea I was not planning on having a rising rate, it is just one more thing to go wrong, I was just going to splice in another regulator to bump the pressure up a little, but if injectors generally run at 43 psi then I will leave it alone.
I have already welded and ported the stock manifolds I think they will be ok for now, they are way bigger than the exhaust port openings.
I have a bunch of mandrel bent 1.5" mild steel tubing I am using for the crossover, and 2.5" mild steel mandrel bent tubing for the exhaust.
Since I do not have the money to do a complete setup at the moment, could I remove the turbines from the housing and build the turbo into the exhaust and run it NA like that for a while? I just do not feel like building two exhausts.
I have never owned a factory/aftermarket boosted car that DIDN'T have a RRFPR. EVER. You don't get around the simple physics of boost vrs fuel pressure. You just don't. I also find it ridiculous to tell a guy (on a budget) to forgo a RRFPR and to buy an EWG when he has a perfectly good internally gated turbo. Everyone has their own opinions and ideas on how to do things, I understand that. But there is a huge difference between doing it the right way and the what the hell were you thinking way.
[This message has been edited by BV MotorSports (edited 06-28-2013).]
So after a little research the stock mechanical limit for the internal evo wastegate is 11 psi. Is this too much to start with? I ask this because on pretty much every turbo setup I have seen, the boost will be set low to start out with.
Also just one more thing to take into consideration... The SD head gaskets I have are definitely taller than stock, effectively lowering my compression ratio. So lets say stock is 8.9:1. So at 8 psi I would have (14.7+8)(8.9) = 202 psi vs 8.5:1 and 11 psi is (14.7+11)(8.5) = 218.45. It is roughly equivalent to running 9.8 pounds of boost on stock compression. Too much?
Also who makes a quality rising rate fuel pressure regulator? I guess the real determining factor for if I get one of not would the opinion of the person who is going to be tuning my car (unless I decide to do it)
[This message has been edited by zkhennings (edited 06-28-2013).]
Don't get me wrong, the rrfpr will allow you to squirt more fuel in there. It just may not be necessary given your choice to use bigger injectors.
The 11psi thing doesn't mean a thing until you actually try it on a 2.8 the reason for that is that when you change the engine it's on, the wasegate effect changes.
In other words, to apply this turbo to a V8, it will take way more air than the turbo can make and you don't need a wastegate at all. Put it on a 3 cyl 1L engine and it will need a big wastegate.
However, beign that we 'think' the airflow of a 2.8 is sorta similar or a bit less than the 4G63, I think the external is a wise choice. This is the reasoning that I used in choosing an external. The internals are pretty small, and I think they are suited to higher psi ranges.
I'd try starting at about 5-7psi. This is the lowest setting on my massive wastegate. It cracks at 4psi, fully open at 7psi.
You'll find as you get into it that wastegates are an art form unto themselves. They can be a bit unpredicatble depending on air flow, temp etc.
Chay
[This message has been edited by Slowbuild (edited 06-28-2013).]
The 11psi thing doesn't mean a thing until you actually try it on a 2.8 the reason for that is that when you change the engine it's on, the wasegate effect changes.
In other words, to apply this turbo to a V8, it will take way more air than the turbo can make and you don't need a wastegate at all. Put it on a 3 cyl 1L engine and it will need a big wastegate.
However, beign that we 'think' the airflow of a 2.8 is sorta similar or a bit less than the 4G63, I think the external is a wise choice. This is the reasoning that I used in choosing an external. The internals are pretty small, and I think they are suited to higher psi ranges.
I'd try starting at about 5-7psi. This is the lowest setting on my massive wastegate. It cracks at 4psi, fully open at 7psi.
You'll find as you get into it that wastegates are an art form unto themselves. They can be a bit unpredicatble depending on air flow, temp etc.
Chay
Ok I understand that on a V8 a small turbo wouldn't push enough air on the cold side to make good boost, so you would not get to the pressure the wastegate opens at anyways, but as long as the turbo flows enough air to make enough boost, shouldn't the size of the wastegate not matter? Regardless of the engine it is on, won't it open when the intake reaches 11 psi? It has a spring and diaphragm that will open at 11 psi of pressure, will this not always be true no matter what engine it is on? Some engines are too small and won't flow enough air to spin the hot side, some engines are too big and the cold side can't push as much air as they need? But other than that, shouldn't the wastegate open at 11 psi?
[This message has been edited by zkhennings (edited 06-28-2013).]
On another note, does anybody know of a wide band o2 sensor/ AF gauge that does not cost over $200? I'm looking to spend more like $100 I was shocked it costs so much
You're correct, the wastegate will open at 11psi on a small engine.
However, if the wastegate does not flow enough (too small) the extra exhaust will contiunue to spin the turbine faster causing continued increased boost. This is referred to as boost creep.
You have to understand, a turbo is a positive feedback device. The exhaust causes the turbo to spin, which feeds more air, which makes more exhaust which feeds more air.....
So, if the wasegate is not big enough to interrupt the process, the turbo will go way past where you want it to, and something goes bang. The wastegate is the only negative feedback in the system. It must be large enough to vent the excess exhaust pressure.
One more thing...I use a Zeitronix unit. It has worked well for quite a while now. The thing you get with it which is very good is the data logging capability. It is well worth the $$. also use an Ostrich II, 7730, $59 and tunerpro4. I highly recommend them if you want to do your own tuning. You have mentioned you do not want to, but you may change your mind in the future. It's nice to in the drivers seat on the tuning thing (Pun intended).
There is a lot of info on here. Some I agree with, some I don't. For example, I don't think that the custom header route will gain you anything. The restriction in the exhaust is the turbo! Don't go too big on the exhaust pre turbo...from what I've read 1.5" for each side is about ideal for the spool/performance balance. Post turbo, go crazy with the 4" elliptical if you want. You probably don't need more than a 2.5" exhaust. Do re-weld/port the stock exhaust manifolds to prevent cracking and improve the stock restrictions.
An intercooler will provide you with increased power potential and increased detonation margain. But, only if it's effective.
Chay
I have to take issue with you on two points. 1st: Yes, for sure, the turbine is the main restriction and thus needs as much velocity/pressure you can get to it. And the stock headers just don't flow. We've had customers report 30hp improvements over the stock units on basically stock engines, that's how poor the design is! BTW: Yeah we've made a few custom sets for turbos in the past but I'm not interested in doing any more.
2nd: It's hard to find a more penny-pinching bunch of bean-counters than auto makers, and they near-always have intercoolers with there turbos. It don't make sense to feed and engine hot air.
For those thinking about doing the same, if you're not prepared to the job right, -which this fellow does seem to desire- then I would suggest not going with a turbo.
Yea I definitely do not want to rush this, I would like to buy quality and I will take time to find the best deals, and I will also do all my own fabrication whenever possible.
Slowbuild, I think the stock wastegate will be ok in that regard because the lancer stock runs 19 psi of boost (with the boost controller) If the wastegate can keep it at 19 I bet it opens enough to keep the boost at 10 psi (unless I totally misunderstand the boost controller and there is a separate bypass for exhaust gas besides the wastegate)
This is what I am using on a 3.4 push rod block and I am pretty happy with it. However, I deliberately limit my boost to about 10 pounds and have no idea as to how it would run at 24 psi.
The stock fuel pressure regulator to some degree will increase fuel pressure under boost. The design with a spring and diaphragm allows it to respond to vacuum pulling on the diaphragm and lowering pressure and likewise just the opposite with pressure pressing on it. It's just not likely to be a 1:1 increase but definitely there will be some with boost. Rising rate pressure regulators were most common in the early years of aftermarket boost when little to nothing was available to allow reprogramming of the OE ECM.
Recall that the stock fuel system has a good bit of reserve and that under stock extremes the injectors are still not run at full duty cycle so if you have the ability to tune the system decreased fuel delivery resulting from boost back pressure can be countered with increased pulse widths to deliver more fuel at a lower rate/hr but longer time until you reach the limit of the system.
Back in the early 90s I addressed this problem by simply removing the cover to the regulator and placing a couple of pennies on top of it to raise the static pressure up to about 50 psi and it worked well on a stock chip although it was a little rich at idle, and with a Ford Probe intercooler sitting in the engine bay plumbed in, I took the 2.8L to 12 psi and that was the engine that a few years later ended up with a broken ring land although it was kept around 8 psi after that.
Francis, I don't like cheap shots. I'm fine with you disagreeing with me, welcome it in fact, but you know where to put your commentary.
If you run an air to air intercooler in a place with no air flow, hence no cooling, you have just introduced a pressure drop with no cooling. How is that gaining anything?
I guess you can say you are intercooled...doesn't make you or your charge any cooler though.
I have a hard time believing that fancy headers would make anywhere near difference with a turbo. Non turbo, for maybe, but 30hp...let's say I'm extremely skeptical it was the only thing that changed to achieve that number.
I was tempted to try the internal wastegates...I'd be interested to see your results. It may work fine. Keep in mind, it's harder to maintain 10psi of boost than 19psi from the perspective of the wastegate, all else being equal.
Chay
[This message has been edited by Slowbuild (edited 06-29-2013).]
I was tempted to try the internal wastegates...I'd be interested to see your results. It may work fine. Keep in mind, it's harder to maintain 10psi of boost than 19psi from the perspective of the wastegate, all else being equal.
Please explain this further, I get what your saying, I understand boost creep, I'm just not sure where in fits in this conversation. with an over abundance of exhaust flow, even with the wastegate fully open exhaust flow could "back up" and have nowhere to go but through the turbine, which will then over boost the system.
It's been my experience that engine displacement (to a degree) doesn't matter, it will just about always take the same amount of air to make 300hp on a 2.0L engine as it would on a 4.0L. Obviously that's a major generalization, but it's true enough for most applications aside from comparing 600cc crotch rockets ro 427 big blocks, but even then it's close.
My only concern with the stock EVO gate, if it is an 11lb gate, I'm worried 11psi is a big first step, I would personally prefer to start at 5-6psi and work my way up from there (but i;m a big baby LOL) . That said, as long as the car has a good solid tune on it, enough fuel and the bottom end can take it all will be well. All you guys with the boosted 60deg's have established the motor can take 11psi, I think I would talk this issue over with the tuner.
I don't disagree with your air/horsepower generalization. There is a slightly variable relationship between CFM (Or should I say kg/min to factor in the density) and hp, with fuel mixture and timing being equal. I think you have me there.
Maybe a better way to say it is, for a given application:
Big turbo, low boost = large wastegate (And also not a great idea unless it's a drag car)
Small turbo, high boost = small wastegate (And not a great idea...lots of hot air at the top end)
Med turbo, med boost = somewhere in the middle...what I think of as a good street setup
The above are extremes of course. There is a lot of grey area in the middle.
You could call ATP, turbochargers.com, Blouch, or one of the other large turbo companies and ask for a specific WGA for the Evo8 turbo. I'd ask for a 6-8psi one for your application. You can always up the boost with a MBC or EBC. Rule of thumb is 2x the rated spring pressure, so a 6psi WGA should be good to 12psi with a boost controller. You don't want to go too low or you may get WG flutter. Dave Buschur would be the man to speak with.
[This message has been edited by BV MotorSports (edited 06-30-2013).]
Is there an adjustable wastegate actuator for the EVO turbo like those for the T3 internal wastegate actuator?
I know Turbosmart makes one for the EVO 7/8/9 but the base spring in 14psi there are most likely lower spring rates available, but at $150-$200 it costs as much as a good External WG
Originally posted by BV MotorSports: IWG is still simple and easy. Requires no additional plumbing etc. Honestly, don't make things more complicated than they need be.
I used to think that BV until I realized the convenience an external wastegate offered in comparison to an internal when it comes to packaging in the cramped engine bay.
I used to think that BV until I realized the convenience an external wastegate offered in comparison to an internal when it comes to packaging in the cramped engine bay.
There is no comparison to be made. An IWG would be even more beneficial in a cramped engine bay. An EWG requires more $$, more space, and more fabrication. In a low boost, low HP car, a person would be nuts to run an EWG in my opinion. There just isn't a need for it. However, if you want it, then by all means have at it.
I used to think that BV until I realized the convenience an external wastegate offered in comparison to an internal when it comes to packaging in the cramped engine bay.
To put it into perspective just type how to plumb in an external waste gate in fewer words than this "Crosover pipe in, Down pipe out" that's 6 words & a coma. I'll wait
There is no comparison to be made. An IWG would be even more beneficial in a cramped engine bay. An EWG requires more $$, more space, and more fabrication. In a low boost, low HP car, a person would be nuts to run an EWG in my opinion. There just isn't a need for it. However, if you want it, then by all means have at it.
I agree, plus I was just looking into lowering a internal waste gates preset PSI and I found some guys using external springs attached to the Internal gate.
also the turbosmart IWG actuators have springs available as low a 3psi and as high as 26psi in the evo I think this is the way to go
How much are those though? If they are a lot then I might as well run an external if I ever chose to use a different turbo. I do like the idea of using an external spring, at least temporarily to break things in.
)
amateur method? LOL
