Cylinder head machining for unleaded...

[JimEB]

Hi all    :)

Popped into a local engineering firm today, to get a feel for how much it'd cost to refurb a PI bare head ready for unleaded use. Crack testing, three angle seats, guides redone as required, new valves (I supply) lapped/ground in. Three day turnaround.

What would, in your experience, be the going rate to such work?

Thanks   ;)

[Clive]

was about £30 a seat down sarf a few years ago....so £200-£250 as a ballpark?
probably depends which part of the country you live a bit.

[JimEB]

Just outside Chichester, almost in the Channel, so that's Down South  ;D

Pricing sounds about right  :)

[Nick Jones]

Paid a bit under £200 in Somerset recently.  Only the exhaust valves need seats.

You'll most likely find that the original head will go on for a good while on unleaded anyway.  While seat recession has been reported by a couple of people in CT they both use their cars hard over long distances.  My Vitesse head did several tens of thousands of miles on unleaded without recession before being removed for other reasons.

Getting suitable seals in the MU will be more pressing unless already done.

Nick

[andy thompson]

Nick_Jones wrote:

Paid a bit under £200 in Somerset recently.  Only the exhaust valves need seats.

You'll most likely find that the original head will go on for a good while on unleaded anyway.  While seat recession has been reported by a couple of people in CT they both use their cars hard over long distances.  My Vitesse head did several tens of thousands of miles on unleaded without recession before being removed for other reasons.

Getting suitable seals in the MU will be more pressing unless already done.

Nick

Hmm - my metering unit on my white PI is running the the same seals as it was in 1992 when I bought it (as a 71 mk2) in Sydney - correct seals are not affected by unleaded - another scam/scare campaign.

[JimEB]

Nick_Jones wrote:

Paid a bit under £200 in Somerset recently.  Only the exhaust valves need seats.

You'll most likely find that the original head will go on for a good while on unleaded anyway.  While seat recession has been reported by a couple of people in CT they both use their cars hard over long distances.  My Vitesse head did several tens of thousands of miles on unleaded without recession before being removed for other reasons.

Getting suitable seals in the MU will be more pressing unless already done.

Nick

Good price!

The reason I'm costing this up is that I suspect low compression on some cylinders. The bottom end seems fine - no rumbles, no oil being burned (clean exhaust, spark plugs look tip top)  :)

[Nick Jones]

Don't suspect, compression test, hot, all plugs out throttle held wide (and do disable the fuel pump first  :))

Nick

[69vitesse]

The US market cars ran on unleaded decades before us without the much touted 'valve seat recession'

[Richard B]

Well in the last couple of years I've had two engines with exhaust valve recession.

The MkI 2.5PI and the 2000 MkII Estate with a late '76 engine.  :'(

[piman]

Hello 69Vitesse,

"The US market cars ran on unleaded decades before us without the much touted 'valve seat recession'"

They also had a 55mph speed limit over there, so I doubt if most cars had a hard life?

Alec

[rotoflex]

piman wrote:

Hello 69Vitesse,

"The US market cars ran on unleaded decades before us without the much touted 'valve seat recession'"

They also had a 55mph speed limit over there, so I doubt if most cars had a hard life?

Alec

Ummmmm, certainly the signs said 55 mph back in the day.

[69vitesse]

rotoflex wrote:

Ummmmm, certainly the signs said 55 mph back in the day.

And all you law abiding citizens studiously obeyed the 55 limit.  ;)