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Hey all, I'm considering changing the head gasket, so while I'm at it, I thought I would get the head shaved to increase compression ratio.
Does this quote sound ok?

"Surface grind cyl head $55.00
Machine & couple up (valve grind) $240.00 + valve stem seals.
Porting work depends on how much money you wish to spend."

What else should I do whilst the head is off?

Advice, from learned ones, sought

Andrew

Oh, just another thing, I got this quote from UMR Engines in Springwood (Brisbane).
Does anyone have a place they can refer me to?

Why are you changing the head gasket?
You will probably gain 1kw from all that.

You do not say why you are doing this. If your car is running well - burning oil- blown headgasket? How many km's. Pricing for machining is easily checkable- ring a few other places. Polishing takes time which you pay at a hourly rate- $100-$150 p/hour? Will it perform better- is it worth the money- your choice.

Reason:
Heater hose blew whilst on the track, did about 2laps / 3mins with an air-cooled engine.
Temperature gauge was all the way to the right when I stopped at the pits.
Running fine since then, no smoke or funny noises, but as they say "better be safe than sorry"

I don't HAVE to get it shaved, I'm just one of those people who live by the "might as well do it while we're at it" motto.

hell yea, polishing the engine always adds power. Nothing goes as fast as shiny shiny metal, just look at all of those superfast cars with chrome engine bits... Not quite as much power added as ur fully sik neons tho bro

No, port and polish on the inside of the head helps to remove some of the inconsistencies left over from the manufactruing process. Less restriction = more power
More specifically, porting is the grinding while polishing is the "making shiny", right?

Jeo wrote:hell yea, polishing the engine always adds power. Nothing goes as fast as shiny shiny metal, just look at all of those superfast cars with chrome engine bits... Not quite as much power added as ur fully sik neons tho bro

No, port and polish on the inside of the head helps to remove some of the inconsistencies left over from the manufactruing process. Less restriction = more power
More specifically, porting is the grinding while polishing is the "making shiny", right?

Yes your second paragraph is correct

The air and fuel flow much quicker and smoother though a polished head compared to a normal head.

But I am also on Par with Bruce as to why you would wanna do this as you wouldn't achieve that much more gains.

Also Considering you would have been travelling at a high speed when you did the hose I believe your engine would be fine otherwise you would have noticed by now.

1red5 wrote:Reason:
Heater hose blew whilst on the track, did about 2laps / 3mins with an air-cooled engine.
Temperature gauge was all the way to the right when I stopped at the pits.
Running fine since then, no smoke or funny noises, but as they say "better be safe than sorry"

I don't HAVE to get it shaved, I'm just one of those people who live by the "might as well do it while we're at it" motto.

Been there, done that - even on the new engine and I didn't bother replacing anything. Unless you're getting massive blowby, oil in your coolant, or coolant in your oil - I wouldn't waste the time and money. If it were screwed I think you'd have noticed by now. IMHO you're wasting your money, just like with the coil packs.

FWIW UMR did the machining on my engine block when I got it rebuilt, but never got any headwork done besides a dip and flattening of the face - I did the spring/seal replacement/fitting myself. UMR's work is of excellent quality.

There ya go. Do nothing. We just saved you a couple of hundred bucks !

Thanks sabre.
I have already contacted people who can check the oil for coolant contamination, vice-versa, so they will be my first port of call before anything else is done.

1red5 wrote:I'm just one of those people who live by the "might as well do it while we're at it" motto.

Hehehe pm me for my bank details you might as well deposit some $$ into it

1red5 wrote:Porting work depends on how much money you wish to spend."[/i]

What else should I do whilst the head is off?

No one is willing to spend enough to take these heads to the next level You answered your own question there

1red5 wrote:Thanks sabre.
I have already contacted people who can check the oil for coolant contamination, vice-versa, so they will be my first port of call before anything else is done.

just keep an eye out for steam outta the exhuast and more so condensation on the oil dip stick and or milky coloured engine oil

irwin83r wrote:

1red5 wrote:Thanks sabre.
I have already contacted people who can check the oil for coolant contamination, vice-versa, so they will be my first port of call before anything else is done.

just keep an eye out for steam outta the exhuast and more so condensation on the oil dip stick and or milky coloured engine oil

Yup
nothing so far, and the level of coolant in the reservoir hasn't gone down.

ANDREW!!!!!

As I said at Lakeside" It ain't broke, leave it alone!!!!

Keep this up young fellar and it's off the the naughty corner for you!!!


The old fellar!!

Terry