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Old 01-28-2012, 11:34 PM   #1
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Default is 15 psi crazy or stupid?

ok so I have ebc hooked up to the Diypnp and am running conservative fuel and ignition table.
Is running 15 psi on the small 2554 just stupid?

I have another engine (04 with 47k) in the garage but dont want to swap for 6-8 months so I can gather the stuff cheap.
So I dont need it to last for ever just 5-10k.
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Old 01-28-2012, 11:39 PM   #2
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Ok stock 1.6 I forgot that part again really small 2554 turbo I know the bigger turbo make more than 200rwhp (the safe limit of 1.6) at 15psi but this small one.
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Old 01-28-2012, 11:51 PM   #3
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You'll be fine...just makes sure your fuelling is right and your spark is conservative.
I'd think you'd be at 200whp with a 2554 at less than 15 psi. Don't make a number like "15" your goal...your target boost should be whatever it takes to make your whp goal.
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Old 01-28-2012, 11:52 PM   #4
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Do itt
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Old 01-28-2012, 11:56 PM   #5
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Quote:
Originally Posted by thirdgen View Post
You'll be fine...just makes sure your fuelling is right and your spark is conservative.
I'd think you'd be at 200whp with a 2554 at less than 15 psi. Don't make a number like "15" your goal...your target boost should be whatever it takes to make your whp goal.

Choices choices.

More boost and less timing and richer afr?

Or

More timing and leaner afr and less boost?

Both can get you the same amount of HP.

Assuming your crankcase vent system can take it, and your air intake temps are ok, I would run more boost and less timing. Safer.
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Old 01-29-2012, 12:23 AM   #6
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Ok thanks I have never thought about my crankcase vent system. what is the issue there?
How do I resolve it?
Currently stock with turbo side running to intake tube and intake side running into the intake runner behind the tb?
I have thought of using a basic filter for the turbo side or the valve cover is this a good idea?
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Old 01-29-2012, 12:28 AM   #7
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I use a little breather filter. It just keeps the vapor from going through your turbo compressor, that all. I think what Faeflora is referring to is don't boost your crankcase.
What injectors are you running?
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Old 01-29-2012, 12:39 AM   #8
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If your goal is 200 whp...with a good tune, you will not need 15 psi.

Edit: 2.25" exhaust is a problem.
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Old 01-29-2012, 12:47 AM   #9
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460cc thanks for mentioning that I will add them to my sig right away.
How do I prevent boosting crankcase. I assume the valve in the tube from intake runner to valve cover is one way. I will check that.
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Old 01-29-2012, 01:36 AM   #10
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Get a pcv valve from a 323 turbo...I have the part number, but I'm on my phone right now. I'll look tomorrow.
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Old 01-29-2012, 01:57 AM   #11
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Quote:
Originally Posted by thirdgen View Post
Don't make a number like "15" your goal.
^ Don't listen to this guy, he has 16" wheels.

You should absolutely make 15 PSI your goal

Then make 16 PSI your goal.

Then 17 PSI.

Then a new engine.

Then 18 PSI.

Then 19 PSI.

Then a new transmission.

(etc)





In all candor, I really don't see the difference between claiming a boost goal, a HP goal, or a ***** size goal. Just make the car as fast as it takes to satisfy you, and then make it slightly faster.
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Old 01-29-2012, 10:01 AM   #12
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Quote:
Originally Posted by Faeflora View Post
Choices choices.

More boost and less timing and richer afr?

Or

More timing and leaner afr and less boost?

Both can get you the same amount of HP.

Assuming your crankcase vent system can take it, and your air intake temps are ok, I would run more boost and less timing. Safer.
how is it safer
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Old 01-29-2012, 10:36 AM   #13
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90, a well-tuned 1.6 using a GT25r with 3" exhaust and all the little stuff can make 220whp at 15psi (I don't think I've seen one make more, but you can get there)... but every little bit needs to be right to get it there.

Your hi-flow cat robs you of a few whp, old tranny/dif fluid maybe another whp or two, crappy or dirty air filter maybe another one or two.

With your conservative tune, you might only be making 180-190whp at 15psi... but you could achieve that same 190whp at 10psi with a less conservative but more optimal tune. That same "optimal" tune at 15psi will get you closer to the 220whp accepted upper limit of a GT25r on a stock 1.6.

I'd rather run a better tune at lower boost... better tune means quicker spool and smoother overall operation. I'd spend a couple hundred bucks to have a good tuner put it on a dyno and tweak you a couple good maps... I bet you'd find that right now, you could have more power on less boost with a still acceptable margin for safety, better engine response, and better overall reliability.
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Old 01-29-2012, 11:50 AM   #14
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Doesn't the 2554 starts to be inefficient and producing a lot of heat at that psi level?
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Old 01-29-2012, 12:07 PM   #15
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I ran my 2554 on a 1.6 at 17psi. It starts to fall off after 15. The gain from 15 to 17psi was small.
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Old 01-29-2012, 12:18 PM   #16
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Great this is just the info I was looking for thanks guys.

Regarding=
'In all candor, I really don't see the difference between claiming a boost goal, a HP goal, or a ***** size goal. Just make the car as fast as it takes to satisfy you, and then make it slightly faster. "

Joe bro I have really appreciated your posts and your knowledge. I am not trying to brag I know 80% of people on here make more power than me. I just dont want to spend 2-300 dollars dyno tuning a set up I will be changing in 6 months. So I wanted to make sure I was only pushing the limit not stepping over it by a mile.


Thanks

Brian
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Old 01-29-2012, 12:24 PM   #17
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Quote:
Originally Posted by 90 Turbo View Post
I just dont want to spend 2-300 dollars dyno tuning a set up I will be changing in 6 months.
That's more than enough to tune about 8 cars...
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Old 01-29-2012, 12:35 PM   #18
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I'm of the opinion anymore that I can do a better job tuning my car than most on the dyno. I say tune it yourself until you know you you've got the setup you want. I feel I can probably get 85%-90% of all I can get out of my setup. I learned that it is very easy to throw away money on a dyno until you know MS settings inside and out.

With proper knock detection and a little bit of theory written into the software, I think autotune for spark is not far away.
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Old 01-29-2012, 12:44 PM   #19
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autotune for spark would be amazing. I guess you would need some sort of knock sensor to make that work.
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Old 01-29-2012, 01:09 PM   #20
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I was trying to say 200 to 300 dollars not 2300 dollars.
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