DragRaceResults.Com    Bracket Talk    Bracket Talk Forum  Hop To Forum Categories  Tech Talk - by Abruzzi    Cylinder Head Flow Numbers
Page 1 2 
Go
New
Find
Notify
Tools
Reply
  
Cylinder Head Flow Numbers
 Login/Join
 
DRR S/Pro
Picture of "The Bender"
posted
As we all know, flow numbers aren't everything, but they are meaningful. That being said look at these and let's discuss them. I'm not saying what head it is or who built it and tested them. I will say these are intended for a 390-430 ci in engine.

I .200 160 E 122
I .300 255 E 170
I .400 330 E 213
I .500 371 E 240
I .600 390 E 254
I .700 394 E 261


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR Top Comp
Picture of Curly1
posted Hide Post
If those are Small Block Chevy they are really good heads. Probably high end recent 18*


https://postimg.cc/gallery/np3zpruo/
"Dunning-Kruger Effect"
-a type of Cognitive bias where people with little expertise or ability assume they have superior expertise or ability. This overestimation occurs as a result of the fact that they do not have enough knowledge to know they don't have enough knowledge.

Before you argue with someone ask yourself, "Is this person mentally mature enough to grasp the concept of a different perspective?" If not there is no point to argue.

4X NE2 CHAMPION. 2020 TDRA NE2 Champion
 
Posts: 3945 | Location: United States of Texas | Registered: April 02, 2011Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
posted Hide Post
Not SBC


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR Trophy
Picture of NC3x58
posted Hide Post
I would think enough compression (12.5:1 & up) those flow numbers seem to be on par with some of the LS3/LS7 aftermarket stuff and those are making around 650-750 or more hp 376-427ci.


Nick Craig

1971 Camaro Split Bumper
376ci LS3
 
Posts: 410 | Location: Ohio | Registered: December 28, 2013Reply With QuoteReport This Post
DRR Trophy
Picture of Jerry Kathe
posted Hide Post
I think you may get as many opinions as participants – lol.
In what way will they be used? Target RPM band?, fuel choice?, N/A or ?, and are you primarily interested in crankshaft numbers or ET slips – and obviously if its ET slips, and you have to plan around fixed conditions (car weight/leave point/trans type/# of gears ….etc) lots more info needed.

And if its not SM GM….must be a mopar BB – LOL!

About to sign off for the day , may not be back until sunday or monday morning, follow up then.


Jerry Kathe
 
Posts: 138 | Location: SW Ohio | Registered: November 11, 2015Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
posted Hide Post
Not BB Mopar.

Not LS

CR 13.5:1, 6000-7400 RPM, race gas

Bracket car 3200#, PG, 950 cfm carb.


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR Elite
posted Hide Post
quote:
Originally posted by "The Bender":
As we all know, flow numbers aren't everything, but they are meaningful. That being said look at these and let's discuss them.

I disagree, they are meaningless as to an indication of how a given car/combo will perform on the track. The larger the port the more air it will flow. You want the greatest flow from the smallest port when comparing/considering heads and mid lift flow not peak is everything.

All advertised big flow numbers are good for us selling heads to the naive and misinformed.
 
Posts: 13522 | Location: NJ | Registered: August 20, 2000Reply With QuoteReport This Post



DRR S/Pro
Picture of "The Bender"
posted Hide Post
Stock head CC for this engine are 190, the heads I gave the flow #'s for are 205 CC. So, not a bunch bigger, volume wise.......

Stock intake valve size 2.06, these heads have a 2.165 valve

Heads with better flow numbers will almost always perform better on the track, unless the original heads are too large already. In this case the original heads are stock heads and designed for a daily driver production car/engine with 50 less cu in than the engine these heads are going on, not to mention this engine will be a race engine with a higher RPM operating range than the stock engine.


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
Your goals should be stated but here's some info for you:

- They should support up to 725 to 775 HP (assumes all other parts are sized accordingly)
- the E/I ratio is about 65% so it will want more duration on the EX side for your cam.
- Port air speed is another key factor missing
- Your carb size is a good size for the 700HP range
-Can't comment on your target RPM until you list the CID of the motor.
 
Posts: 2136 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
quote:
Originally posted by "The Bender":
Stock head CC for this engine are 190, the heads I gave the flow #'s for are 205 CC. So, not a bunch bigger, volume wise.......

Stock intake valve size 2.06, these heads have a 2.165 valve

Heads with better flow numbers will almost always perform better on the track, unless the original heads are too large already. In this case the original heads are stock heads and designed for a daily driver production car/engine with 50 less cu in than the engine these heads are going on, not to mention this engine will be a race engine with a higher RPM operating range than the stock engine.


Ed & The Bender

Air speed matters, too much and too little will hurt performance. Need to pay attention to increasing the intake valve size on a small port head, the flow bench can lie here! If the larger valve increases air speed too much by increasing air flow, the engine will not produce the power that the flow number indicates! In fact it will make less power than the same head with the smaller valve!!! Once the intake port goes into choke velocity it's over! This will occur sooner with the larger intake valve and therefore make less HP!!
 
Posts: 2136 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
posted Hide Post
quote:
Originally posted by TOP38:
Your goals should be stated but here's some info for you:

- They should support up to 725 to 775 HP (assumes all other parts are sized accordingly)
- the E/I ratio is about 65% so it will want more duration on the EX side for your cam.
- Port air speed is another key factor missing
- Your carb size is a good size for the 700HP range
-Can't comment on your target RPM until you list the CID of the motor.


420"

Cam has 10° more duration on the exhaust side @.050

This head has a short intake port, so 205cc is not really small in this case


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
quote:
Originally posted by "The Bender":
quote:
Originally posted by TOP38:
Your goals should be stated but here's some info for you:

- They should support up to 725 to 775 HP (assumes all other parts are sized accordingly)
- the E/I ratio is about 65% so it will want more duration on the EX side for your cam.
- Port air speed is another key factor missing
- Your carb size is a good size for the 700HP range
-Can't comment on your target RPM until you list the CID of the motor.


420"

Cam has 10° more duration on the exhaust side @.050

This head has a short intake port, so 205cc is not really small in this case


I was just gonna ask you that, what's the ports average CSA? CC's are good to know once you know what heads your talking about, but a blind number is meaningless, cross sectional area is what really counts.
 
Posts: 2136 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
posted Hide Post
quote:
Originally posted by TOP38:
quote:
Originally posted by "The Bender":
quote:
Originally posted by TOP38:
Your goals should be stated but here's some info for you:

- They should support up to 725 to 775 HP (assumes all other parts are sized accordingly)
- the E/I ratio is about 65% so it will want more duration on the EX side for your cam.
- Port air speed is another key factor missing
- Your carb size is a good size for the 700HP range
-Can't comment on your target RPM until you list the CID of the motor.


420"

Cam has 10° more duration on the exhaust side @.050

This head has a short intake port, so 205cc is not really small in this case


I was just gonna ask you that, what's the ports average CSA? CC's are good to know once you know what heads your talking about, but a blind number is meaningless, cross sectional area is what really counts.


That I do not know.

What I can tell you is that the port measures 2.00x1.875 at the gasket surface and does not narrow down on it's way to the valve.


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
quote:
Originally posted by "The Bender":
quote:
Originally posted by TOP38:
quote:
Originally posted by "The Bender":
quote:
Originally posted by TOP38:
Your goals should be stated but here's some info for you:

- They should support up to 725 to 775 HP (assumes all other parts are sized accordingly)
- the E/I ratio is about 65% so it will want more duration on the EX side for your cam.
- Port air speed is another key factor missing
- Your carb size is a good size for the 700HP range
-Can't comment on your target RPM until you list the CID of the motor.


420"

Cam has 10° more duration on the exhaust side @.050

This head has a short intake port, so 205cc is not really small in this case


I was just gonna ask you that, what's the ports average CSA? CC's are good to know once you know what heads your talking about, but a blind number is meaningless, cross sectional area is what really counts.


That I do not know.

What I can tell you is that the port measures 2.00x1.875 at the gasket surface and does not narrow down on it's way to the valve.


Any idea of the port centerline length? Or you can list the head and I may have that.. PM me if you want to keep it a secret! LOL

I will take a look at the numbers with the info you listed and get back to you
 
Posts: 2136 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post



DRR S/Pro
Picture of "The Bender"
posted Hide Post
PM me your cell # and I'll send you a good picture of the port.

It is not a common head, I doubt you'd have any info on it.........


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR Trophy
posted Hide Post
Dam they look like Profiler BBC 174 320cc's but they don't have the rest of the criteria.

Lift Intake CFM Exh CFM % Exh/Int
0.200 164 129 79%
0.300 228 162 71%
0.400 288 198 69%
0.500 337 235 70%
0.600 380 255 67%
0.700 395 265 67%

https://www.profilerperformanc...24-degree-heads.html


1.34 9.42@ 142.41 1.29 5.97 @ 114.00 @ #3251 Better in 2022
427 BBC by S&S Speed Center, AFD, Enderle MFI by Spud Miller
Trackside Products, Sepanek Racing T400, Dynamic converter, Autoweld, Santhuff, Smith Racecraft,
His real name is Richard but they call it "**** Fords Body Shop"
 
Posts: 105 | Location: upstate NY | Registered: January 15, 2018Reply With QuoteReport This Post
DRR S/Pro
Picture of "The Bender"
posted Hide Post
quote:
Originally posted by 69427:
Dam they look like Profiler BBC 174 320cc's but they don't have the rest of the criteria.

Lift Intake CFM Exh CFM % Exh/Int
0.200 164 129 79%
0.300 228 162 71%
0.400 288 198 69%
0.500 337 235 70%
0.600 380 255 67%
0.700 395 265 67%

https://www.profilerperformanc...24-degree-heads.html


Not even close.....LOL


272" Spitzer
540 Chevy
The Blower Shop XR1
FTI XPM Series Converter
FTI Level 6 Powerglide
3.69@199
.916 60'

2017 Bradenton Heads Up Madness
Open Outlaw Champ

2018 PDRA T/D #5
2019 PDRA T/D #2

2020 Retired From T/D Competition....

2020 Bradenton NMCA Hemi Shootout Winner

2021 getting back into bracket racing with a Gen3 Hemi powered 87 Cutlass.
 
Posts: 3092 | Location: Yes | Registered: July 08, 2009Reply With QuoteReport This Post
DRR Elite
posted Hide Post
I'm confused what the question is here.

I personally like flow numbers. They are one part of the overall description of how a head works. You shouldn't look at the flow by itself of course. But it certainly is not meaningless. For a combo that needs more flow, I would always prefer a lazy port that flows really well to a tiny port that flows very little. Some drag applications can be very very forgiving when it comes to port size, since many have a very narrow operating band. My current SBC ports are larger than ideal for the flow they have. But with 7000 rpm stall, 7600 shift, and 8100 finish line......the combo really didn't care about the extra port volume. That's not to make the equally ignorant statement that port volume doesn't matter. It all needs to be taken into consideration.


Foxtrot Juliet Bravo
 
Posts: 6337 | Location: Illinois | Registered: July 08, 2004Reply With QuoteReport This Post
DRR S/Pro
posted Hide Post
quote:
Originally posted by "The Bender":
PM me your cell # and I'll send you a good picture of the port.

It is not a common head, I doubt you'd have any info on it.........


Making a few assumptions based on the valve size and port entry dimensions the air speed should be OK. Unless there is a sizeable push rod pinch in the port, the ports throat just below the valve should be the smallest CSA which is what you want. At 88% of the valve OD, your average air speed here is around 340 FPS using the head flow data listed. This number is also higher then it would be is the intake and carb or TB where also mounted on the head during the flow test as the actual flow through the intake system will reduce total air flow (CFM) readings. How much depends mostly on the intake used.

So what are your target goals for this combo?

PM also on its way.
 
Posts: 2136 | Location: Tewksbury, MA,USA | Registered: November 03, 2000Reply With QuoteReport This Post
DRR Trophy
posted Hide Post
quote:
Originally posted by "The Bender":
Not even close.....LOL


I figured as much, I just thru a dart at it. Smile


1.34 9.42@ 142.41 1.29 5.97 @ 114.00 @ #3251 Better in 2022
427 BBC by S&S Speed Center, AFD, Enderle MFI by Spud Miller
Trackside Products, Sepanek Racing T400, Dynamic converter, Autoweld, Santhuff, Smith Racecraft,
His real name is Richard but they call it "**** Fords Body Shop"
 
Posts: 105 | Location: upstate NY | Registered: January 15, 2018Reply With QuoteReport This Post
  Powered by Social Strata Page 1 2  
 

DragRaceResults.Com    Bracket Talk    Bracket Talk Forum  Hop To Forum Categories  Tech Talk - by Abruzzi    Cylinder Head Flow Numbers

© DragRaceResults.com 2024