Hello fine sirs I have a query a la Z. I have installed an MBC just today. Increasing boost to 14 psi or there about, as I heard that is a safe boost to be running on a stock engine/turbos. I also ran a boost gauge into my cabin as well so I could obviously regulate psi and know what I'm running!! Now, I was just wondering a few things. I've set it up like so... Actuators to T piece. LHS pressure reference point (prp) blocked off, RHS connected to boost controller. Boost controller to t piece. Stock electronic boost control system disconnected. Is this a good setup? Anything in missing? My friend said not to hammer it in 3rd and above gears as the engine can't compensate for the extra boost. Is this right? Thank ye olde lords o Z
Back it off to 12psi if you have stock injectors. 14 is too much IMO. Flooring it in any gear will only kill your engine if you're running too much boost. I run 12 all day long, without issues but the injectors reach about 90% at some points. Before everyone jumps in to point out they ran 14 or more, it's my experience logging boost and rpm that 12.5psi is as high as I would call "safe". Your setup sounds like it's correct.
With stock injectors at 14psi you will more than likely lean out . To run 14psi you would have to upgrade your injectors and a tune . Stock engine is capable of running 14psi so long as you can feed it enough fuel .
Alrighty! Well thanks a lot for the advice guys. I ran 14 Psi for two runs and have tuned it down to 11-12 psi as recommended. So next step is injectors and a tune. I was thinking of saving up and tuning to e85. Anyone had any experiences? I realize this may mean new fuel lines, pump, etc.
Disagree with both of the above, but not what you asked so anyway... "LHS pressure reference point (prp) blocked off, RHS connected to boost controller. Boost controller to t piece." Confused about that bit. Both PRP's as you say should be run to a T piece which would then lead to the boost controller. What do you mean boost controller to t piece? What other mods do you have?
Why do you disagree with above? Interested to hear opinions! Like this: http://i.imgur.com/eU0r2gP.jpg
What I disagree with is not running even 14 PSI on stock injectors - stock coolers, absolutely, but once they're changed 15 PSI shouldn't be an issue. I ran that on my stockers and didn't max the injectors. So long as the air can be adequately cooled (problem 16 PSI + on stockers) it should be fine. That guide is incorrect. Both PRP's should be t pieced together, just the same as the wastegates. The hoses should also be equal length - both waste gate lines and PRP's to the t pieces, equal length hoses. This isn't my area of expertise but a few thoughts jump to mind - with that set up, how would you know if you were overboosting in the blocked turbo pipe? Boost spiking is what I'm told will occur if the lines are not equal length, though someone else will have to explain why. I only have limited knowledge on the subject, but I know how my boost controller is installed.
14 psi for 10 years and 155 compression... on stock injectors and turbos, just some unknown aftermarket (big) intercoolers
Just for reference, not recommending this but my last zed ran 20psi on stock injectors and tune.. Only had a cheap fmic and ebay spec fpr.
with a FPR you can raise the fuel pressure(obviously lol) so higher boost pressures wouldn't be a problem aslong as you can supply it fuel.
Haha okay so this is exactly what I was hoping wouldnt happen. Different opinions from different bros. So basically, Anti, what you're saying is that it would be safe to run around 15-16 PSI with upgraded coolers on stock injectors? Stock injectors are only 370cc and as McLovin mentioned, 12.5 PSI is pushing the 90% cycle threshold. So why would my car not be running lean if I'm squeezing more air into the intake but not more fuel? Is the stock ECU able to compensate for that extra fuel needed? Also, in regards to the MBC setup. I completely understand what you're saying. I also thought this to be a slightly strange setup. What I'm thinking though, with your setup, is that if one side is spiking boost or not getting enough, would that not average out if both PRPs are T joined to the boost controller? Therefore, if one side is 10 PSI and the other side is 12 PSI won't the boost controller be mediating 11 PSI? If that doesn't make sense: if you pour a heavy stream of water down one hose and a light stream down another, when they join they will even out and no side will be visibly more powerful than the other. Thus, the only way to regulate two separate turbos with one MBC is to connect a boost gauge to either one to see what's going on. Another question: is there something that regulates and monitors boost from either turbo and keeps them the same? ie turbine speed, actuator movement etc Anyway, look, I'm really an amateur when it comes to this, but with everything that I've read and heard today this makes sense to me. I could be completely off. I hope this makes sense. Frysie - is that driving like a granny, hoon or in between? haha Hermit - that's a fair effort. I think I'll let you keep that record! I'm sorry, what's an FPR and what's it's function?
I personally do not like MBC's even tho I used one in the past. The Turbo Tech, praised around the net, works alright but its just a ball bearing sitting on a spring. If you want better boost control and over boost protection get a real boost controller like a the Turbo Smart Eboost. I've re-read it. What you're saying is passengers side boost source is blocked off right? then your MBC is taking its boost supply from the drivers side? then it's T'd off to the two waste gates? which is correct. You probably can run more than 12.5psi but should you? IMO no. At least get some data logging software and find out how far you can go. a FPR is a fuel pressure regulator. Anti, I don't agree with joining the boost sources, you should only get a reading from one turbo. Just my opinion. This is a turbo smart diagram for hooking up a ebc for parallel turbos.
If you fellas feel happy offering advice in saying 14-20psi on stock injectors is perfectly fine with bigger intercoolers only then go right ahead . The small stock turbos will see a short life span running over 18psi and your engine will probably need a rebuild not long after that from detonation . Its been said many times that 12psi on stock injectors is the safe limit . Anything over that at your own risk . You think all these guys with new builds and bigger turbos would spend thousands upgrading when they can just crank the boost up to 20psi and get the same result ? This is my opinion , you dont have to listen to me BTW Mclovin , In the tech section (AVCR in my case) and instructions for EBC's your supposed to as Anti mentioned , T peice the two boost pipes with same length of hose then into the EBC solenoid . I suppose they do this to get balanced pressure across the two turbos . Can you offer advice why one boost source would be better ?
What is the benefit of blocking off one PRP? I don't see why you would. I ran 15 PSI and only reached 67% on my injector duty cycle. The ECU will match the air (or attempt to) drawn in by the AFM - more boost, more air comes in, more fuel to suit. So long as the injectors are up to the job.
Ran 16 PSI on Stock Turbos, Stock Engine, Stock Injectors, Stock FPR and Fuel System, but with 2.5" Exhaust, and Larger Aftermarket SMICs for years. When I pulled those Turbos out, there was no shaft play. I had Nistune installed and had the car tuned twice, both separate Tuners told me 16 was my limit, as Injectors were sitting on 90%+, not to mention past 17 PSI on Stockers and you veeery quickly put them out of their efficiency range, and what you think you're making extra by up'ing the boost past that, you lose from the exponentially increased amount of heat generated for your pressurized air and needing to find a better way to cool that air. There is no one exact figure, each car's limit will vary. It's even obvious just reading this read alone, some people reporting hitting 90% duty cycle on 12 PSI, others like me got to 16 PSI before the duty cycle became the limiting factor. As for lengths of hose, did my research long ago and the consensus from different respected sources was that to keep boost as responsive and reliable as possible, two things were always smart things to do, shorten all lines as much as possible, and in the case of two Actuators coming to one Controller, to keep the lines from T-Piece to Actuators equal, to lessen the chances for any boost spikes/fluctuations. As for reading boost only from half of the Engine? Just seems like an unnecessary risk. As Martin said earlier, the other side could be spiking and you wouldn't know. The same principle applies with the boost feedback line. Shorten all lines as much as possible and keep the lines from T-Piece to Feedback Nipple on the Intake Pipes, equal. Your EBC/MBC will see boost faster (shorter lines) and with less fluctuations (equal lengths) To those who doubt the validity of any of this, sure it's one thing talk about this as theory, but that doesn't explain the big list of people from here, who have been in my Zed over the years, and some even having driven it, all remarking the same thing, at how quickly boost came on, and responsive it was in on/off throttle situations. I have dyno sheets showing my boost line, and it is incredibly stable once it hits it's mark. Even now having larger Turbos installed, still rivalling the responsiveness of some other Zed's I've been in with Stock Turbos. To the OP, I wouldn't just wind the boost up to some arbitrary figure that keeps changing from one person to another. Just take it to a Dyno, wind it up to 12, then 14, then 15, then 16, do a few runs and have them check your AFR and Injector Duty Cycle during the runs. Find a figure that works for your engine and problem solved, in any gear. MoulaZX
So your saying your set up had less lag than others ? How did you create less lag with stock turbos ?
Technically speaking a set of properly working 370cc injectors, along with everything else in order should be able to supply fuel for ~370rwhp at 3 bar fuel pressure. Most however are not 100% and you will see a sharp drop in how much the injectors can flow. If 12 is this magical limit, then tell me why do UAS and other performance shops tune them to 15-16psi on stock turbos and injectors? Oh and 20psi on stock turbos and 20psi on bigger ones wouldn't equal the same result in power With an EBC.....
Hah, you funny guy. It's right there in my post, if you chose to skim over it, then I'm hardly going to hold your hand and walk you through it again with smaller words. ...and what SRB-2NV said. MoulaZX
I have stock injectors and stock turbos (but bigger Z1 SMICs). UAS installed a manual boost controller on my car as well as Nistune and turned the boost up to 15 psi. I do a couple of WOT runs a day and have never had any trouble.
