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DEB
Dodge Dakota
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8/17/2005
11:21:26
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 Subject: 5.9L cam timing off?
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Met a guy at the track that claims his 99 R/T was set 5 degrees off at the factory to improve emissions. He had the cam adjusted and claims it made a big improvement in performance. Can anyone confirm this?
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N56629
Dodge Dakota
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8/17/2005
12:11:31
| RE: 5.9L cam timing off?
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It was set 5 degrees off from what? Unless the factory put an offset key in, which I doubt, it's set exactly where they wanted it. Now this guy may think that 5 degrees one way or the other is better but that doesn't mean that the factory setting is off, just off from where he would like it.
I advanced my timing by moving the crank sensor but that doesn't mean that the factory was off. They set it for emmission and I reset it for performance.
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DEB
Dodge Dakota
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8/17/2005
13:59:49
| RE: 5.9L cam timing off?
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"Off" was his claim. The manual spec is 10 BTDC to 2 ATDC at check height .034. The stock cam would be 7 BTDC to be dead on. He just seemed to claim 5 degrees made a difference. Could this be so?
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gen1dak
Dodge Dakota
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8/17/2005
18:42:22
| RE: 5.9L cam timing off?
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First of all, you're presenting incomplete information. The manual (1998 FSM) states the intake valve opens 7 degrees BBDC and closes 62 degrees ATDC.
The exhaust valve opens 56 degrees BBDC and closes 33 degrees ATDC.
Now, where's this 5 degrees coming from? Most performance aftermarket timing gears have multiple keyways that will allow for 4 degrees advance or 4 degrees retard of the cam timing. Advancing the cam improves low-end response some, and softens top-end response. Retarding the cam improves top-end power at the cost of some low-end. There are also offset keys to further customize the cam timing in single degree increments. Typically, with an engine off the production line, the tolerances are such that going for more than 4 degrees can spell trouble. In custom-built engines where the cam is degreed in, etc, this isn't so dicey because there's much more precision relative to tolerances.
So, if he had his cam advanced, yeah, it'll feel better down low, but there are better ways to boost low rpm power without sacrificing upper rpm HP.
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