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  #1  
Old 12-15-2006, 09:44 AM
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Throttle body diameter?

Does anyone know the diameter of each throttle body? I think I remember 52mm, but I can't remember for sure. Thanks
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  #2  
Old 12-15-2006, 10:22 AM
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Quote:
Originally Posted by drivemusicnow
Does anyone know the diameter of each throttle body? I think I remember 52mm, but I can't remember for sure. Thanks
I believe they're around 53-54mm.
-Bill
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  #3  
Old 12-16-2006, 01:16 AM
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My spare set here have an ID of about 62mm...that's EACH!

They flow some serious air!

Matt
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  #4  
Old 12-16-2006, 09:49 AM
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Okay, I actually went out the garage and measured one of my spare TB and it's right there with Matt's -- ~63-64mm dia (each!)
Airflow through the TB is really not a problem
-Bill
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Old 12-18-2006, 08:02 AM
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For those that are curious, dual 64mm throttlebodies is the same as a single 90mm throttlebody.
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  #6  
Old 12-18-2006, 08:33 AM
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Quote:
Originally Posted by Earthworm
For those that are curious, dual 64mm throttlebodies are about the same as a single 90mm throttlebody.
David,
fixed your post.
-Bill (72mm2 up on a 90mm TB)
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  #7  
Old 12-18-2006, 10:12 AM
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ok...well 90.5mm to be more precise.
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Old 12-18-2006, 12:23 PM
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Quote:
Originally Posted by Earthworm
ok...well 90.5mm to be more precise.


-Bill
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  #9  
Old 12-18-2006, 02:14 PM
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Actually I would expect that our dual throttle bodies are much better than a 90mm throttle body. A 90mm (3.5 inch) throttle body opened 35% will let a lot more air through than dual 63mm (2.5 inch) throttle bodies will at 35%. This means you get a more linear throttle application with the duals than you would the single.

To bad we have a crappy idle control valve that is expensive as heck to replace.
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  #10  
Old 12-18-2006, 03:31 PM
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Quote:
Originally Posted by drivemusicnow
Actually I would expect that our dual throttle bodies are much better than a 90mm throttle body. A 90mm (3.5 inch) throttle body opened 35% will let a lot more air through than dual 63mm (2.5 inch) throttle bodies will at 35%. This means you get a more linear throttle application with the duals than you would the single.

To bad we have a crappy idle control valve that is expensive as heck to replace.


35% of 2 64mm TB = 2,252 mm2
35% of 1 90mm TB = 2,227 mm2
-Bill
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  #11  
Old 12-19-2006, 07:09 AM
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Quote:
Originally Posted by SVXRide

35% of 2 64mm TB = 2,252 mm2
35% of 1 90.5mm TB = 2,251 mm2
-Bill
Fixed it for ya
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  #12  
Old 12-19-2006, 09:05 AM
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Quote:
Originally Posted by Earthworm
Fixed it for ya

David,
yeah, every 0.5mm helps!
-Bill
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  #13  
Old 12-19-2006, 02:35 PM
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Quote:
Originally Posted by Earthworm
Fixed it for ya
Yes but its only 50% of 90mm, till it gets to 4000, then its 100% of 60mm.X2.
Just thought I'd clear this up.

Harvey.
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  #14  
Old 12-19-2006, 06:02 PM
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Quote:
Originally Posted by oab_au
Yes but its only 50% of 90mm, till it gets to 4000, then its 100% of 60mm.X2.
Just thought I'd clear this up.

Harvey.
To clear this up you should make a statement which is clear and emphatic. 4000 RPM Just what is inferred in exact terms and what is the point

The full throttle areas in both cases are little different. 90 mm = 6361.74 2x 63 mm = 6234.5. It is also difficult to establish anything of advantage one way or the other, in respect practical linear throttle operation.
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  #15  
Old 12-19-2006, 06:03 PM
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35% TPS reading does not mean that 35% of the surface area of the TB is open. It means that the TB plate is just over 1/3 of the way open. Technically you never have all of the surface area because of the shaft.

The larger the diameter, the faster the Airflow/%TPS ratio increases.

Please correct me if I'm wrong as I am definitely not positive about this, however experience has shown this to be true.
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