single direction flow on msd style bench

[Maxflow]

If I were to block off the exhost side of my bench and only
test in the intake direction,how would I set up the
exhost side and make it repetable. I know you would have to
use a hose and mabe as stub header pipe, but how would
hose size,bends and such affect the accuracy. Also would
this cure the orfice disk leaking problem.

Thanks

[200cfm]

I believe you have to fabricate an adapter to interface from the exhaust port and the cylinder bore adapter. And would have to be strong enough to hold the head and other stuff to set the valve lift. Suspose a hose interface could also work but then you might have depression lost and other resistance added to the path. Sorry, I am not much help on this.

[Thomas Vaught]

What I did was this:

I copied some of Smokey Yunick's past work. See his book.

I use a engine block, mounted on an engine stand, that has the cylinder head bolted to the block. I use a head gasket and a header gasket on the head. I attach 4" pvc pipe to the header I am planning on running. A Pitot tube mounted inside the pvc pipe could read the flow or you could read the flow inside the bench using the orifice plate.

Ford, at their Engine Engineering Building flow stands, uses a fixed length of exhaust pipe attached to the head and then that pipe is attached to the normal head mounting surface. The cylinder side of the head has the right bore diameter for the head so you can simulate the bore effects. Either way will work well.

I personally like the block deal as everyone has an old block laying around.

Tom V.

[200cfm]

Tom V, I like the block/head engine stand concept. And I have several spare blocks. I am going to try that approach. Do you have to keep the entire section that goes back to the bench bore adapter on the bench at 4 inch diameter? Got any photos? Thanks.

[115-1172523331]

There is a definite advantage to playing with smaller toys! The photo shows the entire cylinder, head, and valve adjusting gear for my mini bench. The socket in the foreground is 3/8 inch! -- Doug

Hope the picture is there!

[115-1172523331]

OK, let's try it this way!



Doug

[Thomas Vaught]

Here is a link of a similar set-up: (From years ago)



The guy has been around a long time. Here is the Home link:



Tom V

[Maxflow]

Tom if I attach a hose to a short piece of Header pipe on the head,then back to the bench,
does the hose just need to be bigger than the header pipe or is much bigger better.
Also does the orfice disk on a msd style bench seal ok if used in the intake direction only.

Thanks

[Thomas Vaught]

Smokey and Larry just used large diameter hose for their flow pipes.

Personally I have used 4" pvc to flow single exhaust tubes attached to a cylinder head with no issues and have used 6" pipe on typical 4" race collectors. I like that the PVC is smoother vs the ribbed exhaust pipe that garages use but apparently it works ok in that application: a whole exhaust system at idle. A 10" exhaust pipe seems to be a standard for typical exhaust flow testing.

Tom V.

[Maxflow]

Is that 10" from head port to bench attachment hose?

[Thomas Vaught]

Bench cylinder plate or flow bench hose prior to increase to 4" diameter

Tom V.

[Maxflow]

Thanks for the info.

Maxflow