Originally posted by procyon:
Originally posted by Twisted6:
Funny FAST managed to get the new 4.0L V6 with iVCT to run without an ECU that had VCT controls on it. But what does a low-post count member like myself know about such things?
Please provide more info on this and/or link. The 4.0L SOHC V6 has never had VCT. Not for Explorer, Ranger, SportTrac or the new Mustang. A few prototypes engines were made w/ VCT internally at Ford but that's as far as it ever got. Now the 4.6L 3V V8 used in the new Mustang does have VCT.
Correction: It was the new 3V 4.6 and I found the article here:
http://www.fuelairspark.com/ArticlesAboutUs/Details.asp?ID=1027707949
"The variable cam timing on the Three-Valve motor is controlled by a pulse-width modulated signal from the factory computer. While we can control this using the SCT software on a stock ECU (on a chassis dyno), our FAST management system did not offer this capability. We had been running the testing with the cams in the default position (no electronic signal to the solenoid), and though we could not alter the timing electronically, we could adjust it mechanically.
To illustrate power gains (and losses) offered by retarding the cam timing, we retarded the cams 1 tooth. Changing the cam timing 1 tooth on the cam sprocket was the equivalent of 8.5 degrees (42 tooth sprocket/360 degrees). As expected, retarding the cams increased the power output above 5,200 RPM (to a peak of 369 HP), but dropped the power below that point (as much as 37 lb-ft at 3,000 RPM). The key point to remember from this test is by using the variable cam timing, we can have all the torque offered by the advanced position as well as the power offered by the retarded position."
Driving the Caliber
Side project: The LT-5 Fiero is being born..
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