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Old 04-07-2009, 07:07 PM   #23 (permalink)
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Join Date: Aug 2008
Location: South Dakota
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WonderWagon - '94 Ford Escort LX
Last 3: 51.52 mpg (US)

DaBluOne - '99 Ford Escort SE
90 day: 48.97 mpg (US)

DaRedOne - '99 Ford Escort ZX2 Hot
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Quote:
Originally Posted by rkcarguy View Post
Unless you have milled your head and wish to re-align your timing with an adj. cam pulley, adding one to a SOHC is pretty pointless. Advancing the pulley means all your valves will open sooner but also close sooner, which basically does the same thing as just tweaking your timing instead.
Does it do the basically same thing?
Won't the first affect the amount of air flow at given engine speed and throttle opening - (causing the ECU to adjust timing as well?).
While the second only changes raw timing - which may or may not result in the ECU adjusting timing? (My '99 2.0L has anti-knock sensors. My '93 & '94 1.9Ls don't.)

Quote:
Originally Posted by rkcarguy View Post
On a dohc engine the pulleys can be adjusted to open the intake valves earlier and open the exh. valves later for some gains in HP(or other way for more efficiency).
Most anyone I know of that has tried a SOHC adj pulley on the dyno has found -0- to the be the sweet spot, except on engines with a shaved head obviously.
No shaved head, but the engine has 160K on it; presumably tolerances are no longer OEM.
Were those people tuning for: performance, fuel economy, both?
My primary concern is fuel economy - not sure my sweet spot would be their sweet spot.
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