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Old 04/25/2006, 08:51 AM   #1
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Joined: Mar 05
Posts: 77

Exhaust Questions

I just had new duals put on my CS from front to back. I went with a set of Stainless Aero's that had a really sweet, deep sound but not too loud. Had em installed at a local specialist.. One of the glass packs that were on the car when I bought it had a hole in it and I had a bit of a hesitation and the car backfired when you let off the gas. Sounds cool but I know that it's just not right.. So I was hoping that the new exhaust would solve these issues.

Well, the new exhaust is on, the guy did a real nice clean job and the car sounds sweet, but it didn't solve my original problem(s). As a matter of fact, the backfiring is now amplified with the new exhaust. Has a bit of a spitting sound at idle as well..

So he showed me that there are check valves on the manifold (that come from the smog pump) that according to him are stuck in the open position causing excess air to flow back into the engine, thereby causing these symptoms. There are also some tubes that connect to these check valves that will most likely need to be replaced as well..

So my questions are:
1) Where is the best source for purchasing the valves & tubes and does anyone know exactly what they are called?
2) Does this sound like a reasonable solution to my problems..?

I'd appreciate any input

68 GT/CS, Seafoam Green, 302, 4 Speed w/Air
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Old 04/25/2006, 09:14 AM   #2
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Can you describe the tubes? Where do they go from and to?

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Old 04/25/2006, 09:04 PM   #3
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Posts: 77

The tubes, possibly called head to head tubes run parallel along the valve covers. It appears to be about 1/2" in diameter and drops down to 1/4 where it enters the manifold near each cylinder. Attached atop of the h2h tube is the check valve that I spoke of (possibly called Air Diverter Valves). The valve's, one on each manifold, are round and have approx 3/4" rubber hoses attached which go over and meet at the smog pump. Hope this helps..

68 GT/CS, Seafoam Green, 302, 4 Speed w/Air
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