Cylinder Baffle Connections

[tx_jayhawk]

Is it correct to assume that you should NOT have the independent baffle pieces rigidly connected to each other in any ways (i.e. cylinder 1 and cylinder 3 pieces connected)?

It appears that the standard Vans baffle kit has the pieces "float". I was originally planning to attach my plenum top via a screw that goes through the overlapping pieces of the baffles, but I am wondering if it is inappropriate for those pieces to be connected together (given they normally "float")?

Thanks,
Scott
7A

[cytoxin]

i THINK they are not mechanically connectected so they can be installed in corners..otherwise you would not be able to install them..one could say they also were done that way for expansion. but remember that they are bolted to the heads very near each other. i feel certain that it would be fine to install a plenum on the top such as jeff bordelon (sp) did.
i dont know of any pieces that float they are all bolted on somewhere.

http://www.jeffsrv-7a.com/ENGINE/06-03-16.htm

[N131RV]

The cylinders move quite a bit relative to each other as the engine fires and as the engine warms up. Leaving an "expansion joint" helps keep them from cracking due to the forces imparted by the engine.

Originally Posted by tx_jayhawk

Is it correct to assume that you should NOT have the independent baffle pieces rigidly connected to each other in any ways (i.e. cylinder 1 and cylinder 3 pieces connected)?

It appears that the standard Vans baffle kit has the pieces "float". I was originally planning to attach my plenum top via a screw that goes through the overlapping pieces of the baffles, but I am wondering if it is inappropriate for those pieces to be connected together (given they normally "float")?

Thanks,
Scott
7A

[az_gila]

Originally Posted by N131RV

The cylinders move quite a bit relative to each other as the engine fires and as the engine warms up. Leaving an "expansion joint" helps keep them from cracking due to the forces imparted by the engine.

Definitely. I recently saw a bad reconstruction of baffles on a Great Lakes O-360... the person (I won't call him a mechanic......) simplified things and riveted the two parts of the side baffles together. The arrangement is very similar to our RVs.

After less than 10 hrs. the rivets held, but the aluminum baffle cracked... the cylinders really do move with respect to each other....

This is one place to definitely copy standard practice...

gil A

[cytoxin]

using one piece on the side or bonding them together. just that many people have used the existing baffles and installed a plenum on top. such as jeff and others, the plenum PROBALLY still alows enough flex for individual cylinder movement. good luck

[Shockwave]

Speaking of hard plenums, how would you attach them to the rest of the baffles so they don't leak and they don't crack? Oversize screw holes and rtv?