Engine porn

Slippery P

Well-Known Member
Joined
Dec 8, 2007
Posts
2,849
RDC Crypto
3,344
Location
Valley Center CA.
77FBB4B4-6342-4AB3-8180-5F88708D26A1.jpeg
F2C86106-08DA-492F-B133-6B46FAF167F4.jpeg
 

scottm

Well-Known Member
Joined
Feb 7, 2005
Posts
1,905
RDC Crypto
601
Location
scottsdale AZ
Website
www.cemaz.com
That's beautiful! Building engines is my favorite thing. I am building a new 7.4/454 for my '97 K3500 right now, and here is an exhaust port I did for it. Bargain porn!
 

Attachments

  • IMG_1645.JPG
    IMG_1645.JPG
    233.1 KB · Views: 0

scottm

Well-Known Member
Joined
Feb 7, 2005
Posts
1,905
RDC Crypto
601
Location
scottsdale AZ
Website
www.cemaz.com
AZ I meant my engine is bargain porn compared to those danzios!
 

green787

Well-Known Member
Joined
Jan 2, 2005
Posts
10,930
RDC Crypto
2,695
Location
Southern, CA.
Website
realsound.us
Using the "Flow Bench" at Palomar College in San Marcos, CA. what we discovered is that creating a rough surface traps the air molecules in little pits and eddys thus making the air flow over trapped air.... Air flows over air, better than a polished surface.... A polished surface has "cling"....
Also all that over sized hogging out of the intake manifold does nothing until larger valves are installed in the head..... larger intake and exhaust valves are the key..... Like 1.07 or larger intake valves... Of course the lift and duration of the cam affects it also.....
 

jon coleman

Well-Known Member
Joined
Jan 17, 2019
Posts
11,028
RDC Crypto
6,698
Location
sandiego
' raise the intake, lower the exhaust' thats about all i know, however,polish the exhaust, especially 2 stroke, so carbon crap dont stick, is Mike Mendenhall still the porting guru?
 

Slippery P

Well-Known Member
Joined
Dec 8, 2007
Posts
2,849
RDC Crypto
3,344
Location
Valley Center CA.
Using the "Flow Bench" at Palomar College in San Marcos, CA. what we discovered is that creating a rough surface traps the air molecules in little pits and eddys thus making the air flow over trapped air.... Air flows over air, better than a polished surface.... A polished surface has "cling"....
Also all that over sized hogging out of the intake manifold does nothing until larger valves are installed in the head..... larger intake and exhaust valves are the key..... Like 1.07 or larger intake valves... Of course the lift and duration of the cam affects it also.....
I guess I’m doing it all wrong 😑
 

Slippery P

Well-Known Member
Joined
Dec 8, 2007
Posts
2,849
RDC Crypto
3,344
Location
Valley Center CA.
New class 1 engine for “Sheila” 900hp 8500 rpm, there was a lot of custom machine work in this build to make everything work just right.
95D47F59-701F-412C-A84D-B5D5EEC69FEA.jpeg
89225AC3-DE3F-4F6C-BEA1-75619E13E411.jpeg
 

green787

Well-Known Member
Joined
Jan 2, 2005
Posts
10,930
RDC Crypto
2,695
Location
Southern, CA.
Website
realsound.us
I guess I’m doing it all wrong 😑
When you are all done, just sandblast the surfaces with course grit sand..... Test it on a flow bench if you don't believe me.... Air over Air is better than air over polished anything..... That's why the factories don't really care about the casting marks, and the sand cast roughness.... The limiting factor is valve size.....
 
Last edited:

green787

Well-Known Member
Joined
Jan 2, 2005
Posts
10,930
RDC Crypto
2,695
Location
Southern, CA.
Website
realsound.us
Has anyone here ever tested their BS designs on a flow bench.....??? Resist the urge to be science deniers.....
This is what I used at Palomar College back when we actually cared about cylinder head flow design.....
You "Shade Tree" mechanics may have never seen one.....


Seems to me that $1700.00 to actually know what you are doing is a very small investment......
 
Last edited:

Slippery P

Well-Known Member
Joined
Dec 8, 2007
Posts
2,849
RDC Crypto
3,344
Location
Valley Center CA.
Has anyone here ever tested their BS designs on a flow bench.....??? Resist the urge to be science deniers.....
This is what I used at Palomar College back when we actually cared about cylinder head flow design.....
You "Shade Tree" mechanics may have never seen one.....


Seems to me that $1700.00 to actually know what you are doing is a very small investment......
You mean like this one Green?
Yes we use a flow bench, and the intake manifold surface is not polished. They are finished with 60-80 grit depending on application.
39F82FB2-6147-407F-833C-C408D15C8B30.jpeg
 

scottm

Well-Known Member
Joined
Feb 7, 2005
Posts
1,905
RDC Crypto
601
Location
scottsdale AZ
Website
www.cemaz.com
I have 'some' knowledge here as well, though not nearly as much as green. Here is the stock 7.4L manifold on my heads just last week, verses a EFI Victor Jr. It's safe to say the victor flowed better, though I'm trying to see how well I can make it run and stay emissions legal.
 

Attachments

  • IMG_1661.JPG
    IMG_1661.JPG
    251.3 KB · Views: 0
  • 20211001_150613.jpg
    20211001_150613.jpg
    1.6 MB · Views: 0

scottm

Well-Known Member
Joined
Feb 7, 2005
Posts
1,905
RDC Crypto
601
Location
scottsdale AZ
Website
www.cemaz.com
Slippery, do you use spread bore blocks on your 600+ big blocks?
 
Top