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JoeMag's Avatar
 
Join Date: Jul 2005
Location: Cleveland, OH
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Race engine tuning in "over-run"

For those who have tuned race motors, what sort of fuel "tuning" do you do in over-run? Cut off fuel or have a target AFR you're look'n for?

Old 01-03-2021, 12:40 PM
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Navin Johnson
 
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Cut Off.

Unless you like backfires, pops, and wasting race fuel.
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Old 01-03-2021, 01:13 PM
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Thanks!
Old 01-04-2021, 11:18 AM
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Nearly always a fuel cut.
Old 01-04-2021, 01:57 PM
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Navin Johnson
 
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Quote:
Nearly always a fuel cut.
However there is always someone who wants the fireworks, to be loud, and possibly blow apart their exhaust..
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Old 01-05-2021, 03:25 PM
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Yep. Fuel cut and crank up the timing. Grab that off-throttle decel.
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Old 01-05-2021, 04:26 PM
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Quote:
Originally Posted by TimT View Post
However there is always someone who wants the fireworks, to be loud, and possibly blow apart their exhaust..
Prolly the same guy who pulls a money shift, then says, "but it has a rev limiter on it, why did it bend the valves?? We'd see that once in awhile, too.
Old 01-05-2021, 05:52 PM
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Thanks... how does cranking up timing help w decel if no fuel is going in?

Though I must say I loved the massive flames my 930 racer used to make. One time I glanced in mirror on a shift and they were above rear deck!

Old 01-07-2021, 10:19 AM
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