Official Turbo LSJ thread!!!
08-09-2013, 10:35 AM
#6380
If you can find one for a good price I'd try a mini-afc first. That way you keep airspeed up for a more stable idle even though you're losing some resolution.
08-09-2013, 11:02 AM
#6381
Bullshit. I know you're gonna get all mad because you're just as bullheaded as I am, but I don't care.
That entire text you copied from howstuffworks was for a CLOSED SYSTEM. Which is NOT what an lsj has. So sorry, you're incorrect.
You should have gone a couple links lower on google and you would have found this, which is how ours works:
The PCV valve is only one part of the PCV system, which is essentially a variable and calibrated air leak, whereby the engine returns its crankcase combustion gases to the air intake. Instead of the gases being vented to the atmosphere, gases are fed back into the intake manifold, to re-enter the combustion chamber as part of a fresh charge of air and fuel. The PCV system is not a classical "vacuum leak". All the air collected by the air cleaner (and metered by the mass flow sensor, on a fuel injected engine) goes through the intake manifold. The PCV system just diverts a small percentage of this air via the breather to the crankcase before allowing it to be drawn back into the intake tract again. It is an "open system" in that fresh exterior air is continuously used to flush contaminants from the crankcase and into the combustion chamber.
The system relies on the fact that, while the engine is running under light load and moderate throttle opening, the intake manifold's air pressure is always less than crankcase air pressure (see manifold vacuum). The lower pressure of the intake manifold draws air towards it, pulling air from the breather through the crankcase (where it dilutes and mixes with combustion gases), through the PCV valve, and into the intake manifold.
The PCV system usually consists of the 'breather tube' and the 'PCV valve'. The breather tube connects the crankcase to a clean source of fresh air—the air cleaner body. Usually, clean air from the air filter flows into this tube and into the engine after passing through a screen, baffle, or other simple system to arrest a flame front, to prevent a potentially explosive atmosphere within the engine crank case from being ignited from a back-fire into the intake manifold. The baffle, filter, or screen also traps oil mist, and keeps it inside the engine.
Once inside the engine, the air circulates around the interior of the engine, picking up and clearing away combustion byproduct gases, including a large amount of water vapor which includes dissolved chemical combustion byproducts, then exits through another simple baffle, screen, or mesh to trap oil droplets before being drawn out through the PCV valve, and into the intake manifold. On some PCV systems, this oil baffling takes place in a discrete replaceable part called the 'oil separator'.
That entire text you copied from howstuffworks was for a CLOSED SYSTEM. Which is NOT what an lsj has. So sorry, you're incorrect.
You should have gone a couple links lower on google and you would have found this, which is how ours works:
The PCV valve is only one part of the PCV system, which is essentially a variable and calibrated air leak, whereby the engine returns its crankcase combustion gases to the air intake. Instead of the gases being vented to the atmosphere, gases are fed back into the intake manifold, to re-enter the combustion chamber as part of a fresh charge of air and fuel. The PCV system is not a classical "vacuum leak". All the air collected by the air cleaner (and metered by the mass flow sensor, on a fuel injected engine) goes through the intake manifold. The PCV system just diverts a small percentage of this air via the breather to the crankcase before allowing it to be drawn back into the intake tract again. It is an "open system" in that fresh exterior air is continuously used to flush contaminants from the crankcase and into the combustion chamber.
The system relies on the fact that, while the engine is running under light load and moderate throttle opening, the intake manifold's air pressure is always less than crankcase air pressure (see manifold vacuum). The lower pressure of the intake manifold draws air towards it, pulling air from the breather through the crankcase (where it dilutes and mixes with combustion gases), through the PCV valve, and into the intake manifold.
The PCV system usually consists of the 'breather tube' and the 'PCV valve'. The breather tube connects the crankcase to a clean source of fresh air—the air cleaner body. Usually, clean air from the air filter flows into this tube and into the engine after passing through a screen, baffle, or other simple system to arrest a flame front, to prevent a potentially explosive atmosphere within the engine crank case from being ignited from a back-fire into the intake manifold. The baffle, filter, or screen also traps oil mist, and keeps it inside the engine.
Once inside the engine, the air circulates around the interior of the engine, picking up and clearing away combustion byproduct gases, including a large amount of water vapor which includes dissolved chemical combustion byproducts, then exits through another simple baffle, screen, or mesh to trap oil droplets before being drawn out through the PCV valve, and into the intake manifold. On some PCV systems, this oil baffling takes place in a discrete replaceable part called the 'oil separator'.
08-09-2013, 12:07 PM
#6384
As for tuning you really need to have someone that is a very trusted tuner. You car is only going to be as good as the person tuning it. My tuner and I (I gave him the research I had done on HPT forums for our cars) made the power enrich table richer at higher rpm.
You command more fuel by enriching the PE(eq) table. It takes this value and divides it by commanded AFR. So you can simply tune around it without screwing with the MAF freq table. That PE table is can be a pain in the butt; however, it can also make your dreams come true.
The spool rate causing blown pistons? I am sorry man, not trying to be a jerk but that shows you need to do more research and not just take what people on here say for factual information. Its detonation and bad tuning that ruins pistons, not turbo lag.
08-09-2013, 02:51 PM
#6385
so i had john powell help me out with my pcv system that i bought from him (trying to get it to work with my LSJ) and i asked him a question that he suggested i ask you. i have the hahn stage 5 turbo kit and im burning oil. not alot and it doesnt happen all the time ie: if i were to have bad rings, etc. john told me that i should have a restrictor in the oil feed line? he said that you had the same problem and you installed one.. i coulda swore i read that we didnt need restrictors since we have journal bearing turbos. anyways, i thought my turbo seals are gone so i purchased a rebuild kit.. now im not sure if thats the problem lol. did you buy the whole kit from hahn or did you just buy the s20g from them? also, ******* awesome numbers man. all ive wanted is to hit 400whp and i would be happy lol.
I answered your other stuff in the PM's.
08-09-2013, 07:27 PM
#6386
I have a 3" MAF and it ran out around 20 something PSI with a boost spike of 24 on a 20g now that is a lower CFM than probably some of the Precision turbos that others are running so that 3" is a bad idea in my option but its one you listed above in the quote. Unless you are on a 20g ( I am doing fine with my 3" MAF tube at 24 psi/440whp). I would recommend going to a 3.5 as I believe some have done here.
As for tuning you really need to have someone that is a very trusted tuner. You car is only going to be as good as the person tuning it. My tuner and I (I gave him the research I had done on HPT forums for our cars) made the power enrich table richer at higher rpm.
You command more fuel by enriching the PE(eq) table. It takes this value and divides it by commanded AFR. So you can simply tune around it without screwing with the MAF freq table. That PE table is can be a pain in the butt; however, it can also make your dreams come true.
As for tuning you really need to have someone that is a very trusted tuner. You car is only going to be as good as the person tuning it. My tuner and I (I gave him the research I had done on HPT forums for our cars) made the power enrich table richer at higher rpm.
You command more fuel by enriching the PE(eq) table. It takes this value and divides it by commanded AFR. So you can simply tune around it without screwing with the MAF freq table. That PE table is can be a pain in the butt; however, it can also make your dreams come true.
08-09-2013, 08:42 PM
#6388
Premium Member
Got my car back finally. Went in for a turbo swap on Feb. Engine gave out on the dyno. Thousands of dollars and nearly 6 months later. Mechanic felt the turbo was burning oil. Since I've picked up the car I have not seen any smoke so Im hoping the seals set in..It is a used precission 5857 but I had it rebuilt at theBoostlab. Driving it on no meth and no boost controller and taking it ez for 200-300 miles. Hopefully go full boost and tune if all looks well after break in.
08-09-2013, 09:46 PM
#6390
No, it's a fresh air inlet.
08-09-2013, 10:07 PM
#6391
More people need to understand this, if you get your MAF dialed in, the rest of the fueling is very simple to adjust. It takes time and patience to get a good, accurate MAF tune, especially on a very heavily modded car (like a turbo swap), but once it's there, you can very simply adjust your target a/f in any range and they will be surprisingly accurate.
08-09-2013, 11:01 PM
#6393
What you all are talking about, is trying to improve on a system that you don't even understand to begin with.
To those of you putting huge/multiple holes in your vc and running gigantic lines to the intake tube: guess what? You've effectively cut your crank case vac to a piddly fraction of what even the stock system provided.
This is something so basic and fundamental that I really can't comprehend why so many of you don't get it.
08-09-2013, 11:14 PM
#6394
I dont get what your saying true.
But what I do get is after 2 months of pulls and daily driving is a 150ml of partially condensed water vapor, oil, and burned off gases that dont stay in my engine block. Especially with e85 you have a high content of water vapor. If that crap condensed in the block it could mix with oil and spin rod bearings, ruin the brass journals in my turbo, etc.
six of one, half dozen of the other...
But what I do get is after 2 months of pulls and daily driving is a 150ml of partially condensed water vapor, oil, and burned off gases that dont stay in my engine block. Especially with e85 you have a high content of water vapor. If that crap condensed in the block it could mix with oil and spin rod bearings, ruin the brass journals in my turbo, etc.
six of one, half dozen of the other...
08-09-2013, 11:38 PM
#6395
I dont get what your saying true.
But what I do get is after 2 months of pulls and daily driving is a 150ml of partially condensed water vapor, oil, and burned off gases that dont stay in my engine block. Especially with e85 you have a high content of water vapor. If that crap condensed in the block it could mix with oil and spin rod bearings, ruin the brass journals in my turbo, etc.
six of one, half dozen of the other...
But what I do get is after 2 months of pulls and daily driving is a 150ml of partially condensed water vapor, oil, and burned off gases that dont stay in my engine block. Especially with e85 you have a high content of water vapor. If that crap condensed in the block it could mix with oil and spin rod bearings, ruin the brass journals in my turbo, etc.
six of one, half dozen of the other...
I spent a half hour on the phone with Powell today talking about this very subject. We're going to try to come up with a better solution for you blow through guys, since FAI post maf is out of the question without a maze of check valves, or running a seperate air pump. Or if you don't care about the headache of tuning around a vac leak that you created.
08-09-2013, 11:50 PM
#6397
The way mine is rigged is actually 95 percent what the stock system did on my LSJ. That is why I feel good about it and why I and many others are wondering what the heck you are talking about. (said in sarcasm and with a polite smile as to not offend you)
Let me show you what I mean. (six half dozen...)
I pulled the stock AOS out of the head and remvoed the backfire/flame arrestor yes... my VAC source is just above the stock location, it runs from there to the intake before my turbo (boost source) with a catch can in between. Its always in vacuum, less at low boost (low rpm) more at full WOT.
Stock cars have baffles in place and arrestor installed... their VAC source is at the rear of the VC, it runs from there to the intake before the supercharger (boost source). Its always in vacuum, less at low boost (low rpm) more at full WOT.
My head vac source is pretty much stock configuration with a sheetmetal intake manifold. It functions as stock does.
Let me show you what I mean. (six half dozen...)
I pulled the stock AOS out of the head and remvoed the backfire/flame arrestor yes... my VAC source is just above the stock location, it runs from there to the intake before my turbo (boost source) with a catch can in between. Its always in vacuum, less at low boost (low rpm) more at full WOT.
Stock cars have baffles in place and arrestor installed... their VAC source is at the rear of the VC, it runs from there to the intake before the supercharger (boost source). Its always in vacuum, less at low boost (low rpm) more at full WOT.
My head vac source is pretty much stock configuration with a sheetmetal intake manifold. It functions as stock does.
08-10-2013, 01:47 AM
#6398
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The way mine is rigged is actually 95 percent what the stock system did on my LSJ. That is why I feel good about it and why I and many others are wondering what the heck you are talking about. (said in sarcasm and with a polite smile as to not offend you)
Let me show you what I mean. (six half dozen...)
I pulled the stock AOS out of the head and remvoed the backfire/flame arrestor yes... my VAC source is just above the stock location, it runs from there to the intake before my turbo (boost source) with a catch can in between. Its always in vacuum, less at low boost (low rpm) more at full WOT.
Stock cars have baffles in place and arrestor installed... their VAC source is at the rear of the VC, it runs from there to the intake before the supercharger (boost source). Its always in vacuum, less at low boost (low rpm) more at full WOT.
My head vac source is pretty much stock configuration with a sheetmetal intake manifold. It functions as stock does.
Let me show you what I mean. (six half dozen...)
I pulled the stock AOS out of the head and remvoed the backfire/flame arrestor yes... my VAC source is just above the stock location, it runs from there to the intake before my turbo (boost source) with a catch can in between. Its always in vacuum, less at low boost (low rpm) more at full WOT.
Stock cars have baffles in place and arrestor installed... their VAC source is at the rear of the VC, it runs from there to the intake before the supercharger (boost source). Its always in vacuum, less at low boost (low rpm) more at full WOT.
My head vac source is pretty much stock configuration with a sheetmetal intake manifold. It functions as stock does.
08-10-2013, 09:23 AM
#6399
08-10-2013, 09:27 AM
#6400
The way mine is rigged is actually 95 percent what the stock system did on my LSJ. That is why I feel good about it and why I and many others are wondering what the heck you are talking about. (said in sarcasm and with a polite smile as to not offend you)
Let me show you what I mean. (six half dozen...)
I pulled the stock AOS out of the head and remvoed the backfire/flame arrestor yes... my VAC source is just above the stock location, it runs from there to the intake before my turbo (boost source) with a catch can in between. Its always in vacuum, less at low boost (low rpm) more at full WOT.
Stock cars have baffles in place and arrestor installed... their VAC source is at the rear of the VC, it runs from there to the intake before the supercharger (boost source). Its always in vacuum, less at low boost (low rpm) more at full WOT.
My head vac source is pretty much stock configuration with a sheetmetal intake manifold. It functions as stock does.
Let me show you what I mean. (six half dozen...)
I pulled the stock AOS out of the head and remvoed the backfire/flame arrestor yes... my VAC source is just above the stock location, it runs from there to the intake before my turbo (boost source) with a catch can in between. Its always in vacuum, less at low boost (low rpm) more at full WOT.
Stock cars have baffles in place and arrestor installed... their VAC source is at the rear of the VC, it runs from there to the intake before the supercharger (boost source). Its always in vacuum, less at low boost (low rpm) more at full WOT.
My head vac source is pretty much stock configuration with a sheetmetal intake manifold. It functions as stock does.