[sickvr666]

Anybody w/ a VR6 got this done? A buddy of mine can get it done for me for $50.
The stock compression is 10:1 right? If i go 12:1, will it be worth the $50?
I had it done on my Jetta but, all they did was surface it out to fix a crack so i didnt have the whole sh1t shaved.
Im open for suggestions.....
Later-----------

 

[G60247]

Re: Info. on a shaved head??? (sickvr666)

Is there enough surface there to shave and not have the valves hit the pistons?? I'd look further into for sure.

 

[Scorrado]

Re: Info. on a shaved head??? (sickvr666)

It's called decking and 50 sounds pretty good. It costs about 130 to do a multi angle valve grind which includes resurfacing the head and I don't think it would cost much more to deck it. I'm not sure if understand want you are doing though. Ya know you got to take off the head to do this? And are you planning on doing whole 9 yards? Gaskets, valve job, timing related items, water pump, etc....? BTW, when you have this done your going to have a fresh head with more compression on a tried old bottom end. I would not suggest it. I don't think it's worth the risk of blowing the bottom end out. And if something doesn't give, it will surely reduce the life of the bottom end. My 2 cents.

 

[Scorrado]

Re: Info. on a shaved head??? (G60247)

quote:[HR][/HR]Is there enough surface there to shave and not have the valves hit the pistons?? I'd look further into for sure.[HR][/HR]​

I've inquired about it and was told that you can take a good bit off. Down to where the first (looking from the bottom) thread on the spark plug hole is, which (from looking at my head in the garage) seems to be about .080". Thats a lot of metal. Don't quote me on that. I don't know how high lift cams would affect the situation, probally not good.

 

[sickvr666]

Re: Info. on a shaved head??? (Scorrado)

quote:[HR][/HR]It's called decking and 50 sounds pretty good. It costs about 130 to do a multi angle valve grind which includes resurfacing the head and I don't think it would cost much more to deck it. I'm not sure if understand want you are doing though. Ya know you got to take off the head to do this? And are you planning on doing whole 9 yards? Gaskets, valve job, timing related items, water pump, etc....? BTW, when you have this done your going to have a fresh head with more compression on a tried old bottom end. I would not suggest it. I don't think it's worth the risk of blowing the bottom end out. And if something doesn't give, it will surely reduce the life of the bottom end. My 2 cents.[HR][/HR]​

I planned on doing everything but the bottom end! So i guess ill drop the whole idea

Thanks for input

 

[NoCYet]

How many miles are on the bottom end? The consensus I gottten about the VR6 is that the bottom end is very durable, so you might be ok.

 

[YetiMan]

Re: Info. on a shaved head??? (sickvr666)

With 12:1 compression, i would be worried most about where i was going to find fuel with enough octane to run it properly.

 

[sickvr666]

Re: Info. on a shaved head??? (YetiMan)

quote:[HR][/HR]With 12:1 compression, i would be worried most about where i was going to find fuel with enough octane to run it properly.[HR][/HR]​

91 octane

every gas station has it!!!!!!!!!!!!!!!!!!!

 

[sickvr666]

Re: Info. on a shaved head??? (NoCYet)

93K
Think ill be alright?

 

[radoboy]

Re: Info. on a shaved head??? (sickvr666)

There really isn't too much you can shave from the vr6 head because of it's design. The valves actually protrude from the head a bit. I don't have any numbers of how much is safe to shave but I would suggest a mk4 headgasket over removing .08". Anyone know how thick they are? Mk3 and eariler VR6s are around .065-.068. .08 is a lot to shave from a VR6 head. I'd be worried about piston/valve contact and timing related issues. Not to mention 12:1 is just asking for detonation problems on a VR6. Of course anything is possible For each point in compression you gain maybe 5% in power. Mk4 headgasket will net around 10.6:1 while still keeping detonation to a minimum with premium gas. If this is for a daily driver I would go that route. In any case good luck.

Oh yeah...with 12:1 you are gonna need a lot higher than 91 octane.
Brien


[Modified by radoboy, 5:49 PM 11-28-2001]

 

[VWpowa]

Re: Info. on a shaved head??? (radoboy)

From what i have heard redecking the head shaving it what ever you want to call it wont even raise the compression on the Vr6. the combustion chambers are in the pistons.
later
Brian

 

[Scorrado]

Re: Info. on a shaved head??? (VWpowa)

By golly you are so very right..... why didn't I think of that. Most cylinder heads have a recess where the valves are, so when decked the combustion chamber is smaller = more compression, but on the VR6 the bottom of the is totally flat. So taking metal off the head will not do squat. I guess it would give you the effect of having higher lift cams

, but we don't want to go there.

 

[YetiMan]

Re: Info. on a shaved head??? (Scorrado)

It will also retard the cam timing to some extent
91 octane.... Thats a good one ! make sure your knock sensors are working, you ganna need um


[Modified by YetiMan, 8:54 PM 11-28-2001]

 

[Turn2]

Re: Info. on a shaved head??? (sickvr666)

The VR6 head does not like to be decked. You'll run into hydraulic problems with the lifters in the upper RPM band if you take too much off, not to mention the tensioner trying to take up the slack on the timing chain. The compression is built into the pistons design.

 

[CorradoSLC]

Re: Info. on a shaved head??? (Turn2)

Hey Turn2...it's been a while since I saw you & your GTI at the dyno in Manassas.
Anyway, my head was warped slightly - cleaned up within spec by AWE. I've got about 40k on it. Everything seems fine - I've got a little lifter noise when it's cold, but that's normal.
It's definitely something I'd want done by someone with experience on a VR6 head, though.