thoughts on low vacuum?

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Bextreme04

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Ricko, not seeing this kit available anywhere - it's sold out or not available. Any other suggestions or just get a lighter spring kit?

Went back and adjusted total timing to 36 degrees at 3000 rpm instead of 3800 and it's more responsive but still feels sluggish to about 1800-2000 RPM, then it kicks in.
Is this an automatic or manual trans? It must be a pretty aggressive cam to have vacuum that low, which means it isn't going to like having a low stall converter or to be in lower RPM ranges. If you have an automatic and still using the stock converter, I would expect it to pull against the converter pretty hard at idle in gear and the cam will really want the converter stall to be 2400rpm or higher. You might also just be getting lower vacuum from poor mixture as well. You probably need to do some idle mixture tuning and maybe re-jetting.
 

luna negra

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Good point on trans. It has a TH350. Don't know converter stall but I suspect it's stock.
 

AuroraGirl

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Big cam, and no pcv system would be some factors. Have you tried lower initial timing? Valve adjustment would be another thing.

Also please change out that fuel filter!!! Get a wix, plastic or metal! You're gonna burn your truck down. It's gonna smash on that valve cover perfectly.
he could easily use a "Standoff" bracket meant for plug wires on the valve cover bolt to create a bracket to hold it steady
 

Ricko1966

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Ricko, not seeing this kit available anywhere - it's sold out or not available. Any other suggestions or just get a lighter spring kit?

Went back and adjusted total timing to 36 degrees at 3000 rpm instead of 3800 and it's more responsive but still feels sluggish to about 1800-2000 RPM, then it kicks in.
Get some lighter springs we'll address the vacuum later
 

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