A6 head on A4

[greenmachine9]

is this a direct bolt on replacement? the reason i ask is a have an a6 head laying around and my a4 head needs valve seals...so i thought just put the a6 head on....anyone done this?????

[customchord]

Haven't done it but it will work 100%? There the same head the a6 just has a different intake manifold and cam.

[lost_accord]

^Indeed

And that different cam in the A6 head is good for a adding few ponies.

[cloudasc]

Oh and supposedly the springs are a different part number then a1/a4 springs. Probably a little bit stiffer for the a6 cam too. It is 100% bolt on, just make sure you mill the head before you put it on if you haven't already.

[greenmachine9]

ok...can any machine shop mill the head?

[turbo90accord]

it would be easier and less work to just do the cam and intake manifold. cheaper all around as well.

[Accrdwgnguy]

Valve seals are, like, $20. From Honda. Unless you're talking about the valve seats.

[Granite CB7]

It's also possible to do valve seals w/ the head on the car, I did this not that long ago, went really well. Plus I threw in my camshaft too

[greenmachine9]

already got the a6 IM on the a4

[greenmachine9]

so who do i need to get to do the head milling?

[deevergote]

You don't have to mill the head if it's straight. Milling is only necessary when the head is warped.

Take it to an automotive machine shop. If you can't find any, go to a local performance shop and they'll tell you where to go. The machine shop can test the head for you, and mill it if they have to. Milling will bump up compression a bit, which is good. but it can also have some harmful effects. Plus, once a head is milled to a certain point, it's done. If you blow a head gasket, you'll need a new head.

[greenmachine9]

ok...thanks i will try monday

[foamypirate]

You don't want to "mill" the head, you want to resurface the head. There is a difference. Typically you mill the head to raise the compression ratio, with a resurface, you are just making the head surface true, which often involves removing FAR less material than "milling" the head to raise the compression ratio.

Just trying to clarify on these terms, as they are often confused.

[greenmachine9]

^ good insight...thanks

[deevergote]

You don't want to "mill" the head, you want to resurface the head. There is a difference. Typically you mill the head to raise the compression ratio, with a resurface, you are just making the head surface true, which often involves removing FAR less material than "milling" the head to raise the compression ratio.

Just trying to clarify on these terms, as they are often confused.

That's what I was trying to say... you just said it much more clearly!