MSD style Flowbench Modifications

[Bakerlite]

Hi. I'm going start construction of one of these benches soon. I read that there are some problems with this bench which I would like to address before I start cutting my materials.
The first is the plenum area under the bench top. I have seen where people have added a plenum box above it. Can anyone give me some info on why this is done as I'd rather just make the area bigger under the bench top as it would look neater.
Also are there problems with the flow control valves and the disc orifice plate holes sizes and sealing issues with that plate?

[Brucepts]

This should give you some reading;

http://www.flowbenchtech.com/forum/view ... ?f=3&t=494

http://www.tractorsport.com/forum/viewt ... &hilit=msd

The second link is to the old flowbench forum unfortunately it's missing the pics but the text is still there.

[coulterracn]

I'd advise you to use different motors than those used in the article. I too had started building a flowbench per the information in the article.

Long story short, I now have a PTS DIY flowbench and had to upgrade to better (higher capacity) motors. I was able to flow a small block head but for a monster size port and larger valves you will need at least eight high capacity motors.

Good luck on your build.

[Bakerlite]

larrycavan said
"The MSD bench design had some problems but they were easily corrected. Three specific problems were.

1. Orifice sizes were not correct.
2. The position of the orifice plate allowed for a direct blast of air on the orifice.
3. The rotating orifice plate was prone to leaking.

I corrected all 3 of those problems on my MSD bench and it made a night & day difference. I can flow heads that are tested on SF110 bench and we get numbers within a couple CFM of each other at 10"."

OK, so these are the areas as well as the air valves that I need to look at.
I will see if I can change the position of the orifice plate and put a baffle in the plenum to stop the air from being blown directly onto the orifice.
Seems like a lot of holes in the orifice plate.. Do I really need them all?

[Bakerlite]

I'd advise you to use different motors than those used in the article. I too had started building a flowbench per the information in the article.

Long story short, I now have a PTS DIY flowbench and had to upgrade to better (higher capacity) motors. I was able to flow a small block head but for a monster size port and larger valves you will need at least eight high capacity motors.

Good luck on your build.

Thanks what motors did you upgrade to? How many CFM per motor?

[Brucepts]

Honestly and I'm not trying to self-promote but, do yourself a favor and look at the PTS Style Flowbench. No need to correct any "problem areas" as there are none

Lots of VERY successful hassle free builds already, honest, just ask around

But, if you are set on building an MSD Style Flowbench you already found the resources to help you on your way . . . make the needed changes and enjoy the build.

Welcome to the Flowbench World!

[coulterracn]

Thanks what motors did you upgrade to? How many CFM per motor?

I replaced them with LH9563 from http://www.centralvacuummotor.com/flowbench.htm

Ray

[jfholm]

Welcome aboard! I also suggest what Bruce has stated. Just go with the PTS bench. Simple design and easy to build. In all my years I have found that most of the time the simple solution is by far the best. In this case the PTS bench is well thought out and had been discussed and thought about by many people before it was put to paper. I built one and was just amazed how accurate and repeatable it was. Right now I do not spend a lot of time flowing but when I do I don't want to spend all my time recalibrating and chasing gremlins. With Bruce's bench you don't have any of these problems. I can leave it for months and come back and it is still right on with no gremlins.

John

[Bakerlite]

Thanks for the replys, and I have had a look at the PTS bench, but I'd rather try to build the MSD style one. I do like the idea of the multi hole orifice as opposed to having to unscrew a decklid and fiddle around inside the machine.

[1960FL]

Get rid of the pudding bowls for depression control and use a motor controller, more efficient and less potential for leakage.

as opposed to having to unscrew a decklid and fiddle around inside the machine.

????????

Is your rotating disk going to be precision machined? or just hole saws?

Rick