EFIDynoTuning Forum

you may need to add or make the wire mesh baffle, it keeps oil splash away from the pcv valve opening. The pushrod engines have it.

Say the engine is down 100hp and something major is wrong. I would think it would sound strange. Does it sound normal under load? sound normal idling? Stuck injector or injectors?

If the stock air box has the silencer in it that could be costing some power. Mine never had it, iDK what it looks like or how small the opening is. Just an idea.

I had an f150 with a carb'd 302. The compression was all over the place. some were 180 psi and 2 were down around 165 ish. It still moved the truck just fine. It had a tiny stock type cam and made 200 to the wheels still. my point being that i'm not sure you'd lose much power by giving up a tad on the compression.

looks like you're only shooting it 26 degrees under high load?

Is it stick or auto trans?

maybe triple check the firing order. 5.0 is different than 302.

Did you verify base timing with a timing light?

The pump adds extra air so the catalyst can reburn any fuel residue left after combustion. I'm sure it's more technical than that but that's a simplified explanation.

You could have vacuum leaks at the actuators. Leaks at air pump valves or the hoses.

You could install a test pipe in place of the cat when using the turbo. Keep it free of any exhaust leaks and possibly use header wrap to hold in some of the heat. Use a small turbo and it might be worth it.