V6 Head Porting

[Sammy]

they would have to have made atleast some increase in performance

 

[PaRaDoX]

telling your mates to get out and walk home can also boost the performance of the car.... -300kg lol

 

[Sammy]

that all depends on the size of your mates, head work is there all the time

anyways back on topic hehe ...

this first picture as you can see is of the stock VN V6 inlet port before any porting was done.

then this one is with only some mild porting around the valve boss area, you can go further with this if you like, depends on the effort you wish to put in.

its a similar deal with the exhaust port but its a slightly different design - stock though still.

its not a huge difference here but the angle difference after porting will make all the difference in the exhaust compared to the inlet port because the air coming out would run straight into the valve boss, whereas in the inlet port it still runs past the valve boss, just that the valve boss takes up more room.

and here we have a stock port with stock valve boss area ...

now an enlarged and tidied up port with the valve boss cleaned up abit aswell.

stock inlet port on the left and the other two are in various stages of porting complettion.

and similarly with the exhaust ports, the left hand port has been done and the other two are stock.

 

[PaRaDoX]

nice man, picked up my heads today, 200,000km..... thats 70,000km less than my current ones i couldnt believe how light the inlet manifold is... the heads are heavy bastards but i knew that already, any easy way to remove valves, how much do valve spring compressors cost???

 

[cracker]

interesting, how does the 2nd last picute work though by inlarging the port u are just creating a slitght wider area? instead of one constant width i cant see this helping flow, all looks very good though im impressed, how do you know what ur doing just guessing or do you know that this works?

 

[CSL]

guess work with consistancy accros all 6 i am presuming

 

[greenfoam]

You make templates so they are all the same

 

[Sammy]

i use the inlet/exhaust gaskets to work out how far to take the ports out to, as for the valve area its really guess work for me if they all look the same i'm happy.

i've spoken to my engine machinist about where to port and how far to go and all that stuff but other than that its all just go by what i feel is best.

paradox616: i made my own tool which it like a steel bar with a bit of flat plate welded to it, then the flat plate has a hole cut in it closest to the steel bar then a groove after that, like a 'A' shape .... and how it works is you fit one of the rocker bolts and slot the bottom of the 'A' either side of the bolt, then the hole above that should line up with your valve stem, you lever the valve spring down and then remove the collets then lever back up and the springs and stuff just come off ...

its harder to use than a spring compressor but it was made from spares in the shed

also for your heads i would recommend getting them acid washed and crack tested before you go off and port them, as if they are ****ed its a fair waste of porting time!

 

[Sammy]

and here is a really crappy picture of my tool lol!

 

[Immortality]

i use the inlet/exhaust gaskets to work out how far to take the ports out to, as for the valve area its really guess work for me if they all look the same i'm happy.

I've heard that minimal metal removal is the way to go, if you enlarge the runners to much and increase the runner volume you loose the intake charge velocity and this is bad for making power unless your making a high revving circle track racing engine. cleanup the bowl area and around the valve guide too but leave a little more metal around the exhaust valve guide to help dissapate the heat in the valve stem, even better, get some bronze valve guides fitted while your at it as after 300,000km their gotta be some wear and tear there and a 3 angle valve grind