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Unread 10-05-2009, 09:54 AM   #1
beau
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Punching out throttle body

Its been recommended to me to bore out the throttle body on 98 4.0. Has anybody modified theirs? If so how big, did you get mpg gain, power gain? Any downsides to doing it?
thanks

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Unread 10-05-2009, 10:16 AM   #2
HighLonesome
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You will lose MPGs. More air = more fuel.
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Unread 10-05-2009, 11:17 AM   #3
beau
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Thanks five...make sense. The argument was more air, more power less need to mash the peddle.
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Unread 10-05-2009, 04:23 PM   #4
the88thpianoman
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Quote:
Originally Posted by beau View Post
Thanks five...make sense. The argument was more air, more power less need to mash the peddle.
That's true, but it's not the complete equation. You're getting more air at any given throttle position, yes... so the computer compensates by dumping in more fuel. Really it's just going to make the gas pedal a bit touchier, but it most likely will improve WOT power and acceleration.

I'll be able to comment more specifically in a few days when I get my freshly bored TB back in the mail
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Unread 10-05-2009, 08:26 PM   #5
HighLonesome
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I just removed my Fastman 52mm TB. Back to stock for me. But yea pianoman is right, you'll get better throttle response all around and more HP at WOT, but it's at a cost. When you're only getting 12.5 mpg to start with, that cost is hard to live with.
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