[Ron Sutton]

Originally Posted by glassman

Good Question Ron, not really sure. It was the system on my sbc installed last year, but clearly not designed for the LS...i'd like to know though...

It's not quite common knowledge, but H-pipes & X-over tubes ... and mufflers for that matter too ... need to be placed in a precise location for optimum operation. If they're out of place significantly ... it throws off the timing of the exhaust pulses & they actually run into each other ... and literally "back up" or "clog" flow ... similar to what happens in stop-n-go highway traffic.

Maybe the pulse timing was "OK" for the previous engine & this engine was different enough it caused a problem.

For all our serious cars, we design the system based on these timing pulses.

Best wishes !

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