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Vd=0.7854B2S, CR=Vd+Vc/Vc
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Discussion Starter #1
Flow bench tests/numbers for TBI/TPI intake port 187 casting, aka Swirl port.

These numbers are to correct the misinformation out there about the Swirl port, the flow numbers for the HO head as you will see below cannot be interchanged with the swirl port, the swirl port is in fact a far superior head in this regard.

On this day of testing back in 06 I flowed 3 heads, #1) a HO head # 14101081 in used condition and cleaned up for testing. #2) a 350 smogger with fresh v/v grind # 9889338, (very similar to the 882 casting,) and #3) a TPI/TBI 14102187 with 3 angle v/v grind. Testing was corrected to 28” and done over a 4”bore and a 300 cfm hard edge restrictor plate

First up the HO head.
Valve lift CFM @28" HO 305 int.
0.05............. 25.5
0.1............... 84.2
0.2............... 103.9
0.3 ...............149.2
0.4 ...............162
0.5................159
0.6 ...............159

350 smogger Flow #s similarto a Dart SR
Valve Lift CFM @28' Smogger int.
0.05 ................21
0.1 ..................82.7
0.2 ..................108
0.3 ..................191
0.4 ..................192
0.5 ..................191
0.6

And finely The TPI/TBI
Valve Lift CFM @28" TBI int.
0.05 .................31.3
0.1 ...................88.4
0.2 ...................159.3
0.3 ...................192.6
0.4................... 233.3
0.5 ...................246
0.6................... 245.5

The TBI head with porting , bowl ported in a helix form enhancing cast form, opened up bowl roof.

Valve Lift CFM @28" TBI int.p
0.05 ................25
0.1.................. 88.4
0.2 ..................159.3
0.3.................. 192.6
0.4 ..................230
0.5.................. 248
0.6 ..................253

I Think whom ever designed the swirl port is one smart cookie
 

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I think fbird is implying "flow test correction" for using a different test pressure (not always accurate). If the bench was calibrated with the flow plate immediTely prior to teTing the heads that should rule out most weather effects.
 

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Vd=0.7854B2S, CR=Vd+Vc/Vc
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Discussion Starter #5
The 187 casting head is not a `TPI `head.
The only number that look right are the 350 smoggers `338` casting.

You obviously tested the heads at a much lower test pressure drop than 28`.
You won;t see the flow limiting effect of the swirl vane when tested at low test pressures.
as the port swirl induced by the vane is low.
Test them on a big bench that can test @28" and you will start to see the excessive swirl.
I thought they were used on both engines, I stand corrected

I tested at 14" for peak flow which requires about 1 horse power and a min. 20 amp breaker, it's a decent amount.
I can easily pull 28" at low lift, at higher lift pressure drops as flow increases and I end up at about 14"
28" is the industry standard and represents about 1 atmosphere, but when does any engine ever pull an atmosphere? at the valve maybe halfway down the intake stroke for a split second?
The key to power is high velocity and volume, I don't think volume is an issue so how is velocity and swirl port causing a bad combination?
 

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28" is the industry standard and represents about 1 atmosphere, but when does any engine ever pull an atmosphere? at the valve maybe halfway down the intake stroke for a split second?
The key to power is high velocity and volume, I don't think volume is an issue so how is velocity and swirl port causing a bad combination?

The testing standard has little to nothing to do with what an engine pulls, though that can be a LOT higher than 28". What it does have to do with is an acceptable way to standardize testing parameters and results to allow a meaningful comparison. Since you're using no standard methods you really don't provide any meaningful data.

A well known story about David Vizard is how he used a basic shop vacuum to test for port flow improvements- noting that a decrease in pressure differential should correlate to an increase in flow. This is an "okay" method for doing testing on one head but it does not allow for any other comparisons. The other major fault with this test is that there was no calibration being done, so even these limited results could be unknowingly skewed.
 

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WFO
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IIRC the 14102187 has 1.84" intake valves. Testing/data just does not support ~500 hp potentially or empirically from production as-cast 14102187 heads. Nor do 14102187 heads outperform production Vortec heads in peak or average power, all else being equal.
 

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I thought they were used on both engines, I stand corrected

I tested at 14" for peak flow which requires about 1 horse power and a min. 20 amp breaker, it's a decent amount.
I can easily pull 28" at low lift, at higher lift pressure drops as flow increases and I end up at about 14"
28" is the industry standard and represents about 1 atmosphere, but when does any engine ever pull an atmosphere? at the valve maybe halfway down the intake stroke for a split second?
The key to power is high velocity and volume, I don't think volume is an issue so how is velocity and swirl port causing a bad combination?
The flow bench industry standard of 28 inches is of water not mercury. Given that atmospheric pressure is about 34 feet of water or 29.9 inches of mercury equals 14.7 pounds; 28 inches of water depression isn't anywhere near one atmosphere of pressure reduction.

Bogie
 

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As simplistic as it sounds,I see guys all the time take a engine or head known to do one thing really well and try to change that into something else.Hot Rodding??. Well yes,but there are times you want to multiply that trait of what it does well.................................and call it a day.
 

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Vd=0.7854B2S, CR=Vd+Vc/Vc
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Discussion Starter #13
The flow bench industry standard of 28 inches is of water not mercury. Given that atmospheric pressure is about 34 feet of water or 29.9 inches of mercury equals 14.7 pounds; 28 inches of water depression isn't anywhere near one atmosphere of pressure reduction.

Bogie
How much is it?
 

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Vd=0.7854B2S, CR=Vd+Vc/Vc
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Discussion Starter #14
F-BIRD'88;The problem with the swirl port head is the swirl vane in the port works great at low rpm to enduce strong swirl in the flow at low engine output. But at WOT high rpm there is way too much swirl. Good for low rpm power and efficientcy but restricts limits high rpm power output. .[/QUOTE said:
So what is the too much swirl causing to happen?
If swirl reduces flow how is that?
 

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Vd=0.7854B2S, CR=Vd+Vc/Vc
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Discussion Starter #15
Is the 96-2003 Vortec 305 "520" "059" head considered a swirl head as it has the swirlk vane?

peace
Hog
I have a pair of those, they look like a slightly smaller version of the 187.
I haven't flow those yet
 

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WFO
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Cridder said:
The key to power is high velocity and volume, I don't think volume is an issue so how is velocity and swirl port causing a bad combination?
The following is from a thread, "Garage Ported "193"s (Flow #s)", at the Third Generation F-Body message board.

The links below (from a post by kdrolt), contains info and insight into intake port/combustion chamber-induced swirl/tumble and was written originally by Larry Widmer, one of the earlier proponents of what he calls the "soft head". Perhaps studying his work will give you a better understanding of what swirl can- and cannot- do:

 
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