David Vizard's Pressure Wave Terminator/Termination Box:
You cant upload pics directly to this forum (a shame IMHO) so the
pic of the PWTB is on page 10 here:
(Whole thing is worth a read)
David Vizard Exhaust Article
So basically the PWTB is put at the end of of your Tuned Length 4 (into 2) into 1 Exhaust Manifold
and
Fools the 'Branch' into thinking it's exhausting into open air by cancelling out all the pulses in the exhaust before they go through the muffler/s.
NB
That the rule for
the PWTB is that it must have a volume of at least 8X one cylinder.
Preferably 11 to 15X the volume of one cylinder.
Here is some talk of how well it works:
https://www.460ford.com/threads/pres...on-box.103437/
Here is a video, but I don't think the Box has enough diameter really.
It's more of a 'pipe' than a 'box':
NB
that both builders drilled a number of holes through the flat plates of the box and welded in short lengths of round bar to stop the flat plates from vibrating/resonating and kicking up an awful racket.
For fuel economy:
Your Tuned Length 4 (into 2) into 1 'Banana' Branch would be made of longer, thinner pipes.
(
There are various calculators on the net)
The length of the last, 'into 1' pipe is also critical and thats where the PWTB would go.
Then any muffler system would not have the usual negative effect/s on power/economy..?
Has anyone here tried this??
(NB that a quick look on the net shows that
for most Branches advertised the 4, 2, etc pipes are NOT the same length..!
These 'Branches' are 'tuned' to lighten your wallet! Nothing else)
ANTI REVERSION Exhaust ...er... Doodats:
Even if you have a legit Branch: (same lengths)
The rpms they are tuned for are too high for economy.
Anti Reversion doodats can help here:
Basically they act as Tesla Valves (worth a search) to alleviate reverse flow while both the intake and exhaust valves are both open at TDC at the end/beginning of the exhaust/intake strokes.
This will minimize the backflow of exhaust into the intake tract at low rpms.
Some Discussion:
https://xwebforums.com/forum/index.p...-theory.37045/
Anyone tried these??