Throttle Body Air Foil
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Joined: Feb 2015
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From: SC
Throttle Body Air Foil
During moderate shifting, the throttle stuck at about 4500 rpm. Turns out that the air foil had come loose and jammed the intake butterflies. Shut it down, removed rubber intake line, and re-install the foil. Works fine now, but word to the wise, shut it down promptly, if this happens to you!
Flatulent Dwarf
Joined: Nov 2009
Posts: 729
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From: Poverty Holler NC
During moderate shifting, the throttle stuck at about 4500 rpm. Turns out that the air foil had come loose and jammed the intake butterflies. Shut it down, removed rubber intake line, and re-install the foil. Works fine now, but word to the wise, shut it down promptly, if this happens to you!
later,Tiny
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From: SC
There is a bolt about 3mm dia. and about 5 cm long, that goes through the upper portion of the throttle body into a threaded hole in between the two main plenum air orifices. You need a 7/32 Allen wrench to tighten it. The air foil was probably standard on my1989 convertible, since it was there when I got it in 1992.
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From: SC
Fortunately. yes! When I pulled the rubber "pipe" from the filter housing, the foil and bolt were in there. Maybe luck is better than skill?
So I am already, 11 to 50 higher HP with the airfoil?? I don't believe anything with less than 60-80 hp, and am real skeptical of any of those.
So I am already, 11 to 50 higher HP with the airfoil?? I don't believe anything with less than 60-80 hp, and am real skeptical of any of those.
Burning Brakes
Joined: May 2018
Posts: 942
Likes: 243
From: Fruita CO
Looking at the stock throttle body, one would think the airfoil would improve the air flow. Most of the guesses I've read speculate just a few HP. One thing is for certain, I'd put some loctite on the screw.
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Flatulent Dwarf
Joined: Nov 2009
Posts: 729
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From: Poverty Holler NC
Racer
Joined: Aug 2012
Posts: 338
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I had one on my engine I noticed it really blocked the passage to the iac valve and also the passage that goes to the passenger side valve cover for the pvc system to work how it was designed. Best mod I ever did was remove it and trow it in the trash. Just glad it was given to me and I never spent money on it. The car seemed to idle much better with it removed.
Le Mans Master
Joined: Jun 2009
Posts: 6,528
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From: South Dakota
The air foil does do something, but it is very minor.
I had an '87 with one (and a few other minor mods). With the stock chip it had a slight stumble on initial acceleration. I removed the air foil and the stumble was gone.
I changed the chip to an SLP chip and then reinstalled the air foil. The stumble was still gone.
So my conclusion is that it did make a difference in airflow as evidenced by the stumble appearing. However, there was no noticeable performance increase. So it does do something, but not really helping performance.
The real concern is if the bolt comes loose and goes into a cylinder you could loose an engine. If you decide to take that risk, make sure you use loctite on the threads.
Good luck.
I had an '87 with one (and a few other minor mods). With the stock chip it had a slight stumble on initial acceleration. I removed the air foil and the stumble was gone.
I changed the chip to an SLP chip and then reinstalled the air foil. The stumble was still gone.
So my conclusion is that it did make a difference in airflow as evidenced by the stumble appearing. However, there was no noticeable performance increase. So it does do something, but not really helping performance.
The real concern is if the bolt comes loose and goes into a cylinder you could loose an engine. If you decide to take that risk, make sure you use loctite on the threads.
Good luck.
