Charge tube siZing

oler1234

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What’s everyone running for charge tube siZing these days. 2.5” or 2.0”. Anyone change or swap sizes and have real world experience of the effects. Aerocharger is 2.0” for 90% of the run and then up sizes.
 

bayman

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The charge tube you have won't work? Tic Toc. Need to get out and get these fawkers rockin'! Zipper mouth is callin'!
 

toyz

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oler you didn't get a turbo too did you. i will need a helicopter to keep up now.
 

Bnorth

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I was just looking at a kit that offered an upgrade to 2.5" from their basic kit with 2" but can't remember where, maybe turbo performance? I would think that 2" would be plenty to feed 800cc. 2.5" commonly supports over 400whp in an automobile application so should be plenty for 200-240 on a sled IMO.
 

bayman

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oler you didn't get a turbo too did you. i will need a helicopter to keep up now.

you'll do ok Barry, that 174 gets you around pretty good. I needed to cheat to keep up....then he got involved, and here we are. Dec 1st weekend looks like the test and tune ride if you are out
 

Clode

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2" is more than adequate for a sled
 

ABMax24

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Smallest you can get away with is the best. Bigger pipe = More volume = More air to compress to reach boost = More turbo lag.

Friction loss in a pipe less than 3' long is almost none existant, unless your charge pipe is really small.
 

oler1234

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my thinking that most run 2.5" is that most charge tubes are fabricated out of silicone and the bend radius is really tight compared to hard piping. The friction loss in a tighter bend radius is higher.

assuming 50" long charge tube 2 vs 2.5" is a 35% reduction in total surface area... that's a big number when building boost.

but does the smaller size create friction to the point which it creates additional heat. OR is it irrelevant given this is less than 7psi.
 
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ABMax24

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my thinking that most run 2.5" is that most charge tubes are fabricated out of silicone and the bend radius is really tight compared to hard piping. The friction loss in a tighter bend radius is higher.

assuming 50" long charge tube 2 vs 2.5" is a 35% reduction in total surface area... that's a big number when building boost.

but does the smaller size create friction to the point which it creates additional heat. OR is it irrelevant given this is less than 7psi.

You will not create any detectable heat in your charge air from friction. The only heat you will get is from the compression of the air itself, and that is dependent on compressor efficiency and the boost you are trying to make.

I think you are chasing something that isn't there, the cost of replacing a pipe with a larger one will never pay for itself. Not to mention increased turbo lag due to increased volume.

But if you insist here is a calculator that might help you out, when I put in reasonable numbers into it, 300cfm, 2" pipe 4 feet long at 10psi boost (24 psi absolute) I get right around .1psi pressure drop. Not really enough to notice or be worth chasing. FYI use the imperial calculator on the page.

https://www.engineeringtoolbox.com/pressure-drop-compressed-air-pipes-d_852.html
 

fredw

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Went from a 2 to 2.5 years ago on aero kit, I had also changed dump valve to airbox and increased size.. When I did this mod I had also moved ecm so I was able to use a larger charge tube and direct it strait from turbo to airbox.. Getting rid of as many ninetys

FOUND that spool up is cleaner, charge temps cooler and little easier to clutch.. Some say the extra air volume plays a huge role, I'm thinking its a complete package deal that works well
 
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