24v head on 12v?
 

What is the purpose, airflow? I have heard of it done before, just curious as to what all you have to do. Is it a straight up swap, or does it require anything like changing pistons?

The 24v head would flow more. Pistons would have to change. Inectors may not work quite right, or need to be custom. They are different from 12v to 24v

Everything has to be changed,ie: cam, pistons in the end you get a p-pumped 24valve

So would it sound more like a 12v, or a 24v???

an 18 valve?


Sorry, couldn't resist.[duhhh][duhhh]

Why change the cam???

I was wondering about that, too. My guess is that due to the rocker arm bridges there is a different rocker arm ratio, so the cam has to be different... just a guess.

Cam would work.......you need to change the pistons(different chambers)injectors(correct thread & pop-off) injector lines and headgasket.

Cool, there was a debate on another board where one guy claimed you could just throw the head on, and another said you had to change pistons, then the other guy said no you don't....etc....I wanted to get the info before I posted about something I did not actually know about for sure. I hate it when people do that.

24 valve injectors work fine the way they are

Stock???? there are better ones

How much did you increase the timing? 22°?

should be close to that but I can't remember the exact #

Yes there are better, but when I drove my truck more, stock injectors with the pump tweaking that was done(factory GSK and DV's) got my hx-40 to 50 psi VERY quickly. The truck ran very well, idled nicely and started as good as could be expected in the cold with no intake heater. if you want bigger injectors anyway then have them set for what they should be as long as they don't want a bunch of money to do it because it will run fine set for the vp

The combustion chambers in the 12v is set to the ex side of the piston and the combustion chambers on the 24v is in the center of the piston therefore the 24v head has the inj in the center of the head and would miss the combustion chamber of the 12v piston and wash the walls of the cyl. of oil and score the wall.