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Is it safe for me to drill up to this size??

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Old Aug 15, 2002 | 07:18 PM
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Default Is it safe for me to drill up to this size??

my next size is a 1/4th

but my IAC's are in the 29-36 range, but i still get a little surge off and on. Nothing major though. Would ya'll advise drilling one more time?
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Old Aug 15, 2002 | 08:08 PM
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Default Re: Is it safe for me to drill up to this size??

Check your timing at 800 rpm before drilling larger. It may be low. Your IAC count is fine. You may find if the idle is bad with the A/C on that 900 or 950 works better.

If you decide to go bigger use a real small bit and add a second hole. The area of the hole (and therefore the magnitude of IAC change) really grows fast when the bit size climbs.
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Old Aug 15, 2002 | 09:08 PM
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Default Re: Is it safe for me to drill up to this size??

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ragtop 99:
<strong>Check your timing at 800 rpm before drilling larger. It may be low. Your IAC count is fine. You may find if the idle is bad with the A/C on that 900 or 950 works better.

If you decide to go bigger use a real small bit and add a second hole. The area of the hole (and therefore the magnitude of IAC change) really grows fast when the bit size climbs.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">thanks alot, ill atap her tomorrow
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Old Aug 15, 2002 | 09:10 PM
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Default Re: Is it safe for me to drill up to this size??

btw, what should my timing be at around idle?
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Old Aug 15, 2002 | 10:13 PM
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Default Re: Is it safe for me to drill up to this size??

Believe it or not, I have 3/8" hole in the throttle body! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
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Old Aug 15, 2002 | 11:35 PM
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Default Re: Is it safe for me to drill up to this size??

dont forget the old trooper mod trick
where you add shims on top of the idle
set screw.. I have a 15/64" hole in throttle
blade and a .022" shim on top of idle screw.

To big of a shim and you will throw high idle
codes.. I belive that .022 is 26GA tin maybe 28ga
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Old Aug 16, 2002 | 01:29 AM
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Default Re: Is it safe for me to drill up to this size??

same question here, what should the timing be at idle?
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Old Aug 16, 2002 | 07:42 AM
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Default Re: Is it safe for me to drill up to this size??

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by GeorgeC:
<strong>Believe it or not, I have 3/8" hole in the throttle body! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> </strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">makes my little hole feel small now <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />

anyone know what timing at idle should be around average?
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Old Aug 16, 2002 | 08:08 AM
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Default Re: Is it safe for me to drill up to this size??

harold, get under your tb adjustment screw with a small torx bit and open it a touch manually that way.. brought my idle in line without any more drilling.
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Old Aug 16, 2002 | 09:10 AM
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Default Re: Is it safe for me to drill up to this size??

I raised my idle timing into the mid 20s, I've forgotten the exact figure.

3/8" <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> I would take my foot off the brake and go 20 mph with a hole that size. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
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Old Aug 16, 2002 | 10:50 AM
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Default Re: Is it safe for me to drill up to this size??

I have two #2 pencil holes with my 242/242//114.

Once I install the new heads and cam I will experiment.

My car is idleing at 1100 but I'm sure I can get it down to 950, that is the goal.
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Old Aug 16, 2002 | 05:52 PM
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Default Re: Is it safe for me to drill up to this size??

so you're saying about 25 deg of timing at idle and part throttle?
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