side by side twin turbos?

coon smile said:
lets back track...

can some one take me through the steps to reach 138 psi??
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I was going to ask the same thing. He must be a government accountant. If his math is even remotely correct I have a hell of a boost leak.:hehe:
 
What he is talking about is the pressure in the manifold. because at this point the turbos are not running effiecently it builds up in the manifold which if you do the math equals that,,, from what I can figure
 
This is both very interesting and very confusing, maybe one of you that has the math down could start another thread and we could continue to learn. I just went to a compound setup and I have not really done much "tuning" yet but I would love to learn how.
 
Just some more pics:

Hood_stack_completed_small.jpg



Ad_204_11.jpg



Ad_209_10.jpg
 
morkable said:
What he is talking about is the pressure in the manifold. because at this point the turbos are not running effiecently it builds up in the manifold which if you do the math equals that,,, from what I can figure
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if everyone is figuring 138psi...why can't anyone show the mathmatical steps to arrive at 138psi??
 
coon smile said:
if everyone is figuring 138psi...why can't anyone show the mathmatical steps to arrive at 138psi??
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You know what, I bet I made it up, and now I'm scrambling trying to come up with some bs explanation for it...





Either that or...


Assuming 14.7psia atmosphere:

138psig = 152.7psia

And 152.7psia represents a PR of ~10.38.

Coincidentally, 50psig (his interstage pressure) is 64.7psia or a PR of ~4.4. Now 20psig (supposedly what the second stage is then contributing...) is 34.7psia or a PR of ~2.36.

So what is 4.40 times 2.36 you ask? Well, it's the 10.38 that yields the 138psig of course.


PR is most commonly defined as P2/P1 where P1 = inlet pressure and P2 = outlet pressure. Inlet for the first stage will be atmosphere (14.7psia at sea level) and inlet for the second stage will be the outlet pressure (in psia of course) of the first stage. Hence.... compounds.

So basically, I have no idea where 138 came from. But all that garbage I just typed sure looks cool doesn't it? Looks like I managed to come up with a pretty convincing bs explanation after all.
 
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Sounds logical to me...now if I would have know this before I built the twins I would have been set!
 
Charles said:
You know what, I bet I made it up, and now I'm scrambling trying to come up with some bs explanation for it...

Looks like I managed to come up with a pretty convincing bs explanation after all.
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i dont know who pissed in your cheerios, but no one was calling BS

SORRY for asking someone to show the math
 
coon smile said:
i dont know who pissed in your cheerios, but no one was calling BS

SORRY for asking someone to show the math
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Did post #78 not show up on your computer or what?

The fact that you already read Tate's post and asked for an explanation yet again doesn't speak well for your math skills.


:what:
 
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Charles said:
Well look elsewhere for factual information then. I made every bit of that up in my head.

Besides, the fact that you already read Tate's post and asked for an explanation yet again doesn't speak well for your math skills.

Right?

:what:
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What are you talking about???

PLEASE show me where I said the information was made up, or even better, show me where I called BS. :what:

Tate's post did not make sense until I realized that he was using the word "over" as "divided by"
 
coon smile said:
What are you talking about???

PLEASE show me where I said the information was made up, or even better, show me where I called BS. :what:

Tate's post did not make sense until I realized that he was using the word "over" as "divided by"
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Deleted.

Partway through this I realized I cannot discuss anything with you. Sorry for the confusion.
 
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I would still like to learn more about how to use this info to tune a compound turbo setup. How do you know what would be an ideal pressure ratio and how do you read a compressor map. The math above was helpful, thanks for the explanation Charles.
 
if post #2 is not enough, scroll down to post #8 and click on the link. garret has good information in their turbo tech 1-3
 
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