SUPER DREADNOUGHT -our new flow bench.

[David Vizard]

how many inches can it pull at 0.550" with something like a 195cc sbc head?

Digger,
We have not explored it's capability throughout it's entire range yet as Marvin is still making mods that will increase that. On one random test we did pull about 420 cfm through a 200 cc Ford head at 56 inches but it was not wide open.
DV

[ClassAct]

how many inches can it pull at 0.550" with something like a 195cc sbc head?

Digger,
We have not explored it's capability throughout it's entire range yet as Marvin is still making mods that will increase that. On one random test we did pull about 420 cfm through a 200 cc Ford head at 56 inches but it was not wide open.
DV

Here is a rumor I heard. Again...it's a RUMOR that I can't verify but maybe some on here can say yes it's true or its total BS.

I was told by what I consider to be a reliable source that there were teams in the early 2000's that were flowing at depressions of 100 inches of water and maybe a bit more. If that's true, I don't know how it wouldn't suck your shirt off your back if you got too close to the port.

I've never been able to test above 60 inches and for any decent BB head I could only go about 48 inches but damn the noise is incredible.

[David Vizard]

how many inches can it pull at 0.550" with something like a 195cc sbc head?

Digger,
We have not explored it's capability throughout it's entire range yet as Marvin is still making mods that will increase that. On one random test we did pull about 420 cfm through a 200 cc Ford head at 56 inches but it was not wide open.
DV

Here is a rumor I heard. Again...it's a RUMOR that I can't verify but maybe some on here can say yes it's true or its total BS.

I was told by what I consider to be a reliable source that there were teams in the early 2000's that were flowing at depressions of 100 inches of water and maybe a bit more. If that's true, I don't know how it wouldn't suck your shirt off your back if you got too close to the port.

I've never been able to test above 60 inches and for any decent BB head I could only go about 48 inches but damn the noise is incredible.

Mr, ClassAct,

Yes there were some head shops doing cup car work that were flow testing at big pressure drops.

One Cup car team was actually trying to build a bench that would use 100 PSI for the exhaust. They failed in this endeavor and it was suggested (so the story goes) that they call me in to see if I could solve the problem. Yes I could and a real work pressure ex bench is not that hard to build. However, again as the story goes, their chief engineer said that as a writer I would probable give away their secrets. That, I felt, if this story is so, was a bunch of nonsense. During my life I have signed way more NDA's that even Warp Speed. Back in the day I was so well trusted to keep confidentiality that I could walk where I pleased in at least a couple of F1 shops and in Cosworth.

BTW our high pressure exhaust port flow tests did not reval much other than what we already suspected.

DV

[digger]

It makes sense to me to test at the speeds seen in the engine where practical so you can determine the discharge coefficient that most closely approximates running conditions. So a Mach number circa 0.6 port speed on inlet would be useful which requires a "few" more inches than 28

[GARY C]

how many inches can it pull at 0.550" with something like a 195cc sbc head?

Digger,
We have not explored it's capability throughout it's entire range yet as Marvin is still making mods that will increase that. On one random test we did pull about 420 cfm through a 200 cc Ford head at 56 inches but it was not wide open.
DV

Here is a rumor I heard. Again...it's a RUMOR that I can't verify but maybe some on here can say yes it's true or its total BS.

I was told by what I consider to be a reliable source that there were teams in the early 2000's that were flowing at depressions of 100 inches of water and maybe a bit more. If that's true, I don't know how it wouldn't suck your shirt off your back if you got too close to the port.

I've never been able to test above 60 inches and for any decent BB head I could only go about 48 inches but damn the noise is incredible.

Darin Morgan talks about the Indy Racing Head development program found they had to completely reconfigure the port once they started flowing over 100".

[Tuner]

how many inches can it pull at 0.550" with something like a 195cc sbc head?

Digger,
We have not explored it's capability throughout it's entire range yet as Marvin is still making mods that will increase that. On one random test we did pull about 420 cfm through a 200 cc Ford head at 56 inches but it was not wide open.
DV

Here is a rumor I heard. Again...it's a RUMOR that I can't verify but maybe some on here can say yes it's true or its total BS.

I was told by what I consider to be a reliable source that there were teams in the early 2000's that were flowing at depressions of 100 inches of water and maybe a bit more. If that's true, I don't know how it wouldn't suck your shirt off your back if you got too close to the port.

I've never been able to test above 60 inches and for any decent BB head I could only go about 48 inches but damn the noise is incredible.

William Baldwin https://www.facebook.com/baldwinperform ... 1&fref=tag has one of those mega machines you may be referring to. It began as a SuperFlow 1200 bench (220 Volt 85 Amp rated) that Marvin Benoit subsequently modified for John Reed by adding four more pumps, increasing power consumption to over 100 Amps.

220V x 100A = 22,000W / 746 = 29.5 HP ... Big flow benches like these have serious power.

The standard SF 1200 bench capacity is rated as 1200 CFM at 28 inches, but at higher restrictions, such as 390 4bbls. and 350 or 500 2bbls it will pull well north of 100 inches, not sure exactly how much.

Reed used it for carb work and whatever else NASCAR related ?? Subsequently, Bob Blake obtained it and used it for development of NASCAR 390 CFM restrictor carbs and ?? until NASCAR quit using carbs. Baldwin chased it down somewhere in Indiana and brought it back to N. Carolina and is using it for carb development.

Mark Whitener has a large bench too, not sure about the flow maximum on his.

[Boz-Race Engines]

looks like a bit of a beast there DV, look forward to hearing some results from this weapon

[BigBro74]

I will bet this is a beast -and will help reveal some interesting trends with different types of heads.
David, do you plan to run it in any type of floating depression mode, or with the capacity of this machine, a mode that varies the depression/pressure at different lifts? (not stirring hornets-so just asking DV please)
Thanks - Jason

[MadBill]

It makes sense to me to test at the speeds seen in the engine where practical so you can determine the discharge coefficient that most closely approximates running conditions. So a Mach number circa 0.6 port speed on inlet would be useful which requires a "few" more inches than 28

There are of course crank angles in the induction/exhaust cycles where the pressure differentials are much smaller than 100 "Hg/psi, but any port contour variations between optimization for 100 vs. <10 shouldn't necessarily be decided 100% in favour of the former.

[ClassAct]

It makes sense to me to test at the speeds seen in the engine where practical so you can determine the discharge coefficient that most closely approximates running conditions. So a Mach number circa 0.6 port speed on inlet would be useful which requires a "few" more inches than 28

There are of course crank angles in the induction/exhaust cycles where the pressure differentials are much smaller than 100 "Hg/psi, but any contour variations between optimization for 100 vs. <10 shouldn't necessarily be decided 100% in favour of the former.

I agree. There is more to testing with a flow bench that just testing at 28 inches.

[Malvn]

Here is one of my flow test with my flow bench this is not my best test. Thought I would share this picture
the blue box digital manometer was custom built for my flow bench it has 100" censors across all four channels
the censors actually can go over the 100" with out a problem the Soft ware is awesome .

New Flow Test at 28 1700. CFM 10 33 PM 9 23 2017 001.JPG

[LoganD]

Here is a rumor I heard. Again...it's a RUMOR that I can't verify but maybe some on here can say yes it's true or its total BS.

I was told by what I consider to be a reliable source that there were teams in the early 2000's that were flowing at depressions of 100 inches of water and maybe a bit more. If that's true, I don't know how it wouldn't suck your shirt off your back if you got too close to the port.

I've never been able to test above 60 inches and for any decent BB head I could only go about 48 inches but damn the noise is incredible.

Darin Morgan talks about the Indy Racing Head development program found they had to completely reconfigure the port once they started flowing over 100".

I know of at least 3 flow benches that are used in high end motorsport capable of over 50 kPa depression (200" water), and 800 kPa pressure for exhaust port testing. They are also capable of supplying up to 400 kPa pressure in the intake port to simulate boost conditions while still controlling depression quite accurately. These ports obviously don't flow anything like as much as an IHRA mountain motor, but they do flow quite a bit in the conventional sense. Essentially you can load real inlet, cylinder, and exhaust port pressures from test data during intake and exhaust phases and they'll map it.

The only reason they haven't become more common is that CFD has gotten so, so good. It's much cheaper and much faster to optimize ports on a computer.

[digger]

It makes sense to me to test at the speeds seen in the engine where practical so you can determine the discharge coefficient that most closely approximates running conditions. So a Mach number circa 0.6 port speed on inlet would be useful which requires a "few" more inches than 28

There are of course crank angles in the induction/exhaust cycles where the pressure differentials are much smaller than 100 "Hg/psi, but any port contour variations between optimization for 100 vs. <10 shouldn't necessarily be decided 100% in favour of the former.

Of course but I can't really see optimising shape and velocity profiles based on low speed conditions being better than doing so under the actual conditions of use. Why not optimise for conditions that you want maximum improvement I.e more power

[Malvn]

Here is some more pictures of actual flow test with my flow bench
I was testing to see where the CFM was going to go down and at what Depression
it was going to take to make that happen

Flow Test @ 70 Inches &amp; 72 inches of H2o 001.JPG

[MadBill]

...Of course but I can't really see optimising shape and velocity profiles based on low speed conditions being better than doing so under the actual conditions of use. Why not optimise for conditions that you want maximum improvement I.e more power

I was referring to the changing pressure differentials existing at various crank angles during a single two revolution event, while operating in the desired powerband.