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big_G
10-23-2011, 03:53 PM
I have lived with the loud noise on my ProCharged 'Vette for years. The sound is way too loud on a long cruise. I'm thinking...why not dump the outlet into the exhaust, just behind the collector, like drag racers do with crankcase vapors? My system is dual 3 inch with Hooker Max-flow mufflers...pretty low restriction. Any slight back-pressure up to the surge valve would be offset by boost leakage around the valve butterfly. Anyone see any flaws with this?

camcojb
10-23-2011, 04:08 PM
I would think you'd have exhaust heading back past the surge valve into the intake. Besides the heat going back into the intake, exhaust doesn't have oxygen and would be diluting the incoming air with something that won't burn.

If you're going to divert it, either divert it into the intake system somewhere or run a tube down and out of the engine compartment so you don't hear it.

big_G
10-23-2011, 04:15 PM
I would think you'd have exhaust heading back past the surge valve into the intake. Besides the heat going back into the intake, exhaust doesn't have oxygen and would be diluting the incoming air with something that won't burn.

If you're going to divert it, either divert it into the intake system somewhere or run a tube down and out of the engine compartment so you don't hear it.

I thought about the exhaust heading back up to the intake, but when the valve is open (cruise) the outflow is very high. I have to believe this will overcome any exhaust, which at cruise should be less than 1 psi. Under boost (in my case about 20 psi), I can't believe the exhaust will be much more than 1-2 psi at full throttle. The valve is closed at that time anyways. Maybe I'll take some back-pressure measurements before I proceed.

camcojb
10-23-2011, 04:38 PM
I thought about the exhaust heading back up to the intake, but when the valve is open (cruise) the outflow is very high. I have to believe this will overcome any exhaust, which at cruise should be less than 1 psi. Under boost (in my case about 20 psi), I can't believe the exhaust will be much more than 1-2 psi at full throttle. The valve is closed at that time anyways. Maybe I'll take some back-pressure measurements before I proceed.

I really don't know, you're probably right; I was distracted by the Steelers when I posted that. :) Then it's only if there's any heat transfer up the piping, and if that heats inlet air or harms the o-ring seal most of those surge valves have for sealing to the piping. I just wouldn't do it that way.

bigtime
10-23-2011, 04:52 PM
I use the red closed race valve and plumb it into the intake piping on most street cars we have also put them in the fender with a K&N filter on the end.