Increasing intake air flow
#1
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Model: Cherokee
Increasing intake air flow
I have a 99 Cherokee 4.0 that I had to replace the exhaust manifold so I replace with a header. I am now looking to increase the intake to get better use of the header. I have a K&N air filter but in the stock box. I know installing a bored throttle body will help but funds are getting low. Is there a larger throttle body that will fit the 4.0 that came stock on something else or does anyone have any low budget ideas to help? Thanks Timo
#3
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#4
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Year: 1998
Model: Cherokee
Engine: 4.0
If you have access to a machine shop or have a friend that has access, bore out the throttle body your self on a lathe. There have been some people that were able to do it with a drill press and sand paper. if you are real careful you could use a dremel and a die grinder head.
check this out before the site goes down.
http://go.jeep-xj.info/HowtoTBboring.htm
check this out before the site goes down.
http://go.jeep-xj.info/HowtoTBboring.htm
#5
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
If you have access to a machine shop or have a friend that has access, bore out the throttle body your self on a lathe. There have been some people that were able to do it with a drill press and sand paper. if you are real careful you could use a dremel and a die grinder head.
check this out before the site goes down.
http://go.jeep-xj.info/HowtoTBboring.htm
check this out before the site goes down.
http://go.jeep-xj.info/HowtoTBboring.htm
#7
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Year: 1990
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#9
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Year: 2000
Model: Cherokee(XJ)
Engine: Golen 4.6L
It's a testament to these Jeeps that they can have a huge sucking vacuum leak around the wrong butterfly in the throttle body and still run well enough that people don't realize how bad the leak is.
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Year: 1998
Model: Cherokee
Engine: 4.0
In my throttle body there is not really any more gap between the butterfly and the bore then there was before I bored it it just lays more flat than factory. Even with the small gas that were opened up the IAC will compensate and make sure the idle is where it should be. The only thing that I did with the butterfly is bevel the edges more and make sure it is centered because I knew that it would sit flatter in the bore. I will try to get a picture of it before I leave work today.
#14
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Thanks for the reply's. Think I will try Dans98 DIY first as I live in Colorado and there are thousands of Cherokees around here being parted out ( very popular around here) so I am sure I can pick up a TB cheap enough and follow your thread to bore it myself. Worth a try. Thanks all