Topic: BBC LS5 454 exhaust install questions
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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BBC LS5 454 exhaust install questions.
Corvette Central dual exhaust deluxe kit seems to come with "extra" parts.
My factory assembly manual shows a few exhaust diagrams (with some good clearance measurements), but the pic lumps all engines together.
I would think BBC/454 and SBC/LT1 would have different exhaust pipes...
Page A2 UPC 8 titled "Exhaust System" shows a "close up" of pipes.
It goes exhaust manifold, then (9) packing, then extension (8)- extension? this confuses me.
Why do I need a metal-small-donut-exhaust tube extension (about 2") that goes into the real header pipe?
The flange should pull up the header pipe and sandwich the packing right against the manifold, right?
But then again, why would they send these parts if i didn't need them?
Should I omit the tube extension pieces? They seemingly would choke the exhaust before actually going into the real exhaust pipes.
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The short tube/extension is to hold the doughnut gasket in place, to help keep it from flipping/moving around in use.
hth
Joel Adams
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So all exhaust systems- regardless of engine RPO's- have to use the tube-pipe-neck-down extensions that enter into the exhaust?
Just seems that the "0-ring"/packing would be enough to seal the header pipe up into the exhaust manifold.
Found out hot to install the extension pipe and packing.
Went to Corvette Specialties and saw their exhaust on the shelf. The o-ring packing goes around the extension pipes, to hold and center all the pieces when tightening the bolts.
The neck-down extension pipes look like they would choke the exhaust slightly, but it makes for a fool proof seal because:
(1) the packing, and 2)the pipe goes down into the true header pipe.
Now... I'm struggling with getting the tips aligned. I don't have the fully welded mufflers system (loose mufflers were recommended at CC for install on jackstands).
On one hand, there's too many variables/angles with the un-welded/separate mufflers. You get it situated where you want it, then you bump the head pipe and it swings out of the way.
Still, with a fully welded pair, there's no way to adjust if it, say, it hits the fiberglass quarter.
in Forum: C3 Fuel, Emission Control, and Exhaust Systems
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