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Old 09-20-2004, 02:11 PM
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huge vac leak or cam

will a cam change effect the shift point on auto trans?

before i changed cam, trans (w/shift kit) would hit hard on 1-2 shift

now it shifts lighter

p.s. also have adjustable vac modulator

engine will idle down to 700-800 in gear about 850-950
in park

seems to run ok, slight surging below 2500 rpm

thanks
R.

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Old 09-20-2004, 02:56 PM
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Well, surging quite often indicates a leak . Do a check with some carb cleaner or whatever you prefer to use. What were your old cam specs vs. your new ones?
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Old 09-20-2004, 03:25 PM
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Surging on light throttle also indicates a lean carb if no vacuum leaks are detected. A conditon of booster signal at the carb caused by a longer cam.
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Old 09-20-2004, 05:07 PM
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new cam is comp cam XE268

old cam was isky 2800-6000 rpm.
lift was higher than new one
(measured lobes to check lift- to see if springs would handle new cam, just a double check i did check for coil bind)


thanks
R.

just checked plugs.....they are white

time for jet/rod kit.
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Old 09-20-2004, 05:52 PM
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Before you tear into the carb do a check for leaks. It will cause a system to run lean as well.
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Old 09-20-2004, 08:04 PM
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One thing you can do to check for leaks that`s a little cleaner is use a propane torch, start the engine, turn on the propane, and go around the carb and intake with it, if there`s a leak the engine will pull in the propane and the idle will go up.
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Old 09-20-2004, 09:25 PM
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I like to attach a hose on the end of my propane so that I can further pinpoint the leak. It makes it easier to get behind the engine to (incase the leak is towards the back of the manifold and whatnot).
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