5.9L 12V Performance Discussion of 12 Valve 5.9 Liter Dodge Cummins Diesels with P7100 Injection Pumps Related to Performance and Longevity

24 valve head on a 12 valve block.

Thread Tools
 
Search this Thread
 
  #11  
Old 04-13-2010, 08:33 PM
guhfluh's Avatar
Diesel Fan
Join Date: Mar 2010
Location: Houma, LA
Posts: 97
Likes: 0
Received 4 Likes on 4 Posts
Default

Originally Posted by shortbusdriver
a 24v head does not flow more in all cases
How can you say that? Only if you spend money porting, going OS on valves and/or camming a 12v is it going to flow more than a 24v on the same boost.
 
  #12  
Old 04-13-2010, 09:06 PM
shortbusdriver's Avatar
Diesel Enthusiast
Join Date: Oct 2009
Location: LeRoy WI
Posts: 113
Received 3 Likes on 3 Posts
Default

ever think about why they put runners on high hp engines?
 
  #13  
Old 04-13-2010, 10:12 PM
12valvetater's Avatar
Diesel Bomber
Join Date: Oct 2008
Location: Pennsylvania
Posts: 1,474
Received 35 Likes on 34 Posts
Default

They put runners on because the intake is milled off the head to port the intake side better. What is your point?
 
  #14  
Old 04-13-2010, 10:40 PM
shortbusdriver's Avatar
Diesel Enthusiast
Join Date: Oct 2009
Location: LeRoy WI
Posts: 113
Received 3 Likes on 3 Posts
Default

that is not the reason they put runners on.

Look how the ports are on a 24v vs a 12v.

http://www.zzcustomfabrication.com/head_porting_08.html
 

Last edited by shortbusdriver; 04-13-2010 at 10:44 PM.
  #15  
Old 04-14-2010, 08:26 AM
12valvetater's Avatar
Diesel Bomber
Join Date: Oct 2008
Location: Pennsylvania
Posts: 1,474
Received 35 Likes on 34 Posts
Default

They need runners because the intake is milled off.
 
  #16  
Old 04-14-2010, 08:30 AM
dan33klein's Avatar
Diesel Bomber
iTrader: (-1)
Join Date: Nov 2008
Location: cherry,il
Posts: 1,019
Received 11 Likes on 11 Posts
Default

i swore i thought i read somewhere the 24v head only flows a few cfms over the 12v head, not worth the time or money swapping
 
  #17  
Old 04-14-2010, 09:42 AM
shortbusdriver's Avatar
Diesel Enthusiast
Join Date: Oct 2009
Location: LeRoy WI
Posts: 113
Received 3 Likes on 3 Posts
Default

Originally Posted by 12valvetater
They need runners because the intake is milled off.
There are many intake manifolds that dont have runners.

They need runners to separate the ports to prevent "distortion" between the cylinders. 24v ports share two valves so they will not flow as much in high performance applications.
 

Last edited by shortbusdriver; 04-14-2010 at 12:38 PM.
  #18  
Old 04-14-2010, 09:49 AM
12valvetater's Avatar
Diesel Bomber
Join Date: Oct 2008
Location: Pennsylvania
Posts: 1,474
Received 35 Likes on 34 Posts
Default

When you mill the intake off you need them either way.
 
  #19  
Old 04-14-2010, 12:48 PM
Red_Rattler's Avatar
High Tech Redneck

Join Date: Nov 2007
Location: Columbus WI
Posts: 6,730
Received 496 Likes on 397 Posts
Default

Originally Posted by dan33klein
i swore i thought i read somewhere the 24v head only flows a few cfms over the 12v head, not worth the time or money swapping
Yup that's true. In stock form they are pretty "close" to each other.
 
  #20  
Old 04-14-2010, 01:09 PM
guhfluh's Avatar
Diesel Fan
Join Date: Mar 2010
Location: Houma, LA
Posts: 97
Likes: 0
Received 4 Likes on 4 Posts
Default

Maybe not worth the money because of the expense, but that's a lot of personal opinion on what money is worth. I dont have the money, but others might.

Milling the intake off, porting and making new intake manifolds is serious work. I can make my lawnmower head flow more than a 24v with enough work and money.

If the same is done to a 24v head, do they still flow more than a 12v?

85_305 is partially correct. When dealing with forced induction, flow is not always a big deal and can be easily overcome by more boost. Still, the more efficient an engine is, the more power it will always make. The same setup with only one better flowing part in the system will make more power.
 


Quick Reply: 24 valve head on a 12 valve block.



All times are GMT -5. The time now is 01:39 AM.