Thread: Maximum head can be milled?

THanks for the replies!! I do appreciate it!

But pulling the engine to do pistons isn't quite as "easy" nor quite as "affordable" as milling the head.

I mean, I'm all for slapping in some 12.5:1 slugs, but rules won't allow me to do that. I could get away with a stock replacement type piston, but I doubt that would help much if at all. I don't recall seeing any 10:1 pistons out there. I'm also not worried about cam timing. Milling the head will have a very minimal effect on cam timing, and it would only serve to retard the cam timing a bit which would very likely be beneficial to my set up. Either way, I've got adjustable cam gears that I can use to bring cam timing back in line if it doesn't like the change after milling.

I'm building this car to race in NASA Performance Touring class. I can mill the head, but swapping in some domes would put me out of my class.

what about ve pistons? those are technically a stock replacement piston?

Are you allowed to weld quench areas into the head instead to raise the compression and help combustion?

Yes. Although that is an extremely costly upgraede that I would not be willing to do. I would rather swap a VQ35 into the car and get re-classed before I put $3K into a DE head.

I was thinking DIY (except for the resurfacing part).
I guess you'll have to wait and see if anyone knows the max you can mill that head.

Milling the head to raise compression is not the best idea, usually when milling a head you would need a thicker head gasket to compensate for the area that was resurfaced so your timing is not thrown off, when raising and lowering compression the propped way to achieve this, is through your pistons, and valves or molding or shave combustion chamber.

nissanwulf, Disney is limited to his mods by racing class regulations.

Hey Disney, are you allowed to use adjustable cam sprockets to compensate for the cam timing change when milling the head, or are those against the rules too?

Yes, no rules against cam spockets.

And i've worked the math out a bit, but being as I don't yet know just how much i'll mill the head I don't have an exact number. Regardless, what I came up with was milling the head .2mm would cause my cam timing to retard approx. 1 degree. I can live with that. I was planning on dynoing the car with the cams advanced and retarded to see if either way helped my curve. I have a dyno so I can experiment with that as much as I need.

yes, if thats the case, and you have cam gears mill .2mm and run the thinnest h/g i think the thinniest one is .9mm.

get on the dyno and just adjust the cams to make the proper gains.

stratton.

About this HG.....

I work for Nissan NOrth America and can therefore get screaming deals on the stock HG. I was planning on running that but I understand it's about 1.1mm? Where do I source this .9mm gasket?

Thanks!!!!!