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Old 10-13-2015, 06:40 PM   #21
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I mean, if I'm running 18 psi of boost measured at the intake manifold, won't I just be reducing the pressure ratio further up the line (ie, less restriction for the compressor to push against to make that level of manifold pressure)?
the more restrictions you remove the more easily you make the power, or make more power with less heat and pressure, should you want to

agreed with others though that it's more for safety than power
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Old 10-13-2015, 06:43 PM   #22
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the more restrictions you remove the more easily you make the power, or make more power with less heat and pressure, should you want to

agreed with others though that it's more for safety than power
Boost is a measure of restrictions. A turbo won't produce any boost if there are no restrictions. It will just blow a lot of hot air.
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Old 10-13-2015, 06:45 PM   #23
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like some of your posts

kekeke

ilu
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Old 10-13-2015, 06:48 PM   #24
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like all of your posts

kekeke

ilu
FTFY
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Old 10-13-2015, 07:53 PM   #25
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Boost is a measure of restrictions. A turbo won't produce any boost if there are no restrictions. It will just blow a lot of hot air.
I am really surprised that this isnt covered by performance magazines or websites in articles.

Boost is a measure of restriction VS airflow.

It would save a lot of people installing tiny JDM cams into their turbo cars that are running 15psi but could be on 25, for example.

Dann
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Old 10-13-2015, 07:57 PM   #26
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I am really surprised that this isnt covered by performance magazines or websites in articles.

Boost is a measure of restriction VS airflow.

It would save a lot of people installing tiny JDM cams into their turbo cars that are running 15psi but could be on 25, for example.

Dann
Depending on the turbo it might be happier at 15psi than 25 though. The whole system needs to work together.
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Old 10-13-2015, 10:22 PM   #27
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To paraphrase Good to Great by Jim Collins, you gotta rinse your cottage cheese if you want to maximize performance.
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Old 10-14-2015, 01:41 AM   #28
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My thought was that reducing the resistance would mean more flow at a given psi (I'm assuming that flow deficiencies between the intake and the compressor outlet are compensated for by the compressor putting out more pressure to push past the resistance), which would put me beyond the surge line at a lower RPM. Which I'd like a lot.

I'm just not sure I see any obvious paths to significant gains in this area and pretty much every avenue of experimentation seems pricey.
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Old 10-14-2015, 01:43 AM   #29
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Intake manifold? Bigger piping? Different engine?
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Old 10-14-2015, 02:11 AM   #30
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I'm already running a flattop and a 99 head. My intake piping could be slightly improved, but not by a ton. It's got good bends and it only changes diameter at the intercooler and the throttle. I guess a bigger throttle, port matched to the intake would get air across the throttle a little quicker, but I'm not predicting anything amazing there.

Bigger engine- would work, but my precious dollas. Strokers are ******* expensive.
Different engine entirely- would work but dollas. Swaps make strokers look frugal.
Cams- less likelihood of gains than stroker or swap, but also less money. Also more effort to get this to work. I would be pretty happy if I could find a drop in intake cam that added a bunch of lift with nearly stock duration.

Bigger piping- could work, but wouldn't this make the entire setup more laggy by forcing the turbo to fill up more volume before the intake manifold gets up to pressure?
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Old 10-14-2015, 02:15 AM   #31
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if you're asking what would be ideal, then yes super smooth and short piping with really gradual transitions from compressor outlet all the way to tb would be ideal. and then a well flowing IM that's a perfect compromise of plenum volume, runner length/id/shape/position, with cnc machined head with +1 or +2 valves, with a perfect exhaust mani, and a well breathing hotside, and a really smooth downpipe with minimal bends and huge id, and...and...and

bust most cars here don't have all that. and you're still working with a BP that won't hold a candle to more modern engines. So you find the line between "good setup" and "money pit" and call it good.


*edit: just the fact that you keep saying "moe dollas" means you're about done
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Old 10-14-2015, 02:28 AM   #32
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For me, the miata has basically been a 15 year exercise in me going "that's cool but I can do it for cheaper" and then, just as I think I have triumphed over the laws of engineering and physics, the car breaks in some horrible new way and I learn a valuable lesson.

edit: Yeah, having a budget sucks, but wife said I can have xidas when I get the engine back together, so it's not all shitty.
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