this has yet to be proven ...

the 24v head has two smaller valves that are not very strong as the 12v head uses two bigger valves. the only advantage would be the injector placement. IMO port the 12v head.

 

The high power guys what heads do they use on there trucks? A 12v head will flow plenty for 99% of the diesel performance bunch. I'm switching one right now from a 24 to a 12v head. Main reason it needed a head and was going P-pump so its alot easier to go that route.

From what I've seen the diffrence in injector placement makes the p-pumped 24's hard to tune. You see lots of conversions but very few of them ever show big numbers on a hobby budget!

 

well the 24 valves do have smaller valves but that does not mean they are any less strong in fact it is better to have more valve that are smaller for more heat transfer area. you really should have known.

 

so why do 24 vavles have problems with there valves and seats? I'll stick with my 12 valve head as the post above you states

 

I will say that the valve seat problems lies in the seats themselves. But it more than obvious a 12 is the way to go. Harry used to have the flow data on the piers site. The 24's compairson to the 12v showed that the 24 ported to stage 2 flowed similar to a ported 12v. BUT the stage three the 24v showed to flow about 200 CFM more, Now is that worth the cost of switching? Not to mention when taking a 24v and 12v head to what they considered stage three (at the time) the 24 is weaker and more prone to cracking due amount of material removed. The 12v is also pretty weak (12 and 24 at stage 3 are too weak for my liking). With that said, you could spend a fortune on buying a head, Ringing it, and porting to make a 24v swap worth a while in a CFM Aspect ? As I said before, Up until the 800 RWHP range a factory 12v head (port size and so on) is more than adequate! Porting a head isnt really even benificial except for spool up and EGT reasons. Not to mention, You change a well designed head when porting, So now we've taken a head that was properly matched to air flow and was PUSHED TOO the limit with 4 valves per chamber. If we run a burr to deep or get an angle wrong we've completely screwed that perfect flow already there , and turned it into a turbulent mess! Even if the ports are made bigger and their polished, they could possibly flow less. This lesson has even been learned by many of the porting pro's in the industry and rather easy to do, SO if you decide to port your own head, take your time and go slow!