Cylinder head advice

[Neil MAC]

Whats the general thoughts of getting the cylinder head converted from unleaded to leaded.

Is it worth it?

has anybody had it done?  If so where and how much also was there any difference in performance?

Had my cylinder head off about two years ago and noticed that the valve seats were worn and some of the valves were sat lower than the others, however when I re-ground them they did sit well and the car then performed well on the RBRR.

Any advice and recomendations welcome, at the moment I am leaning to the prospect of getting the cylinder head converted to unleaded (thinking long term). Would also rather go to some one recomended


Thanks
Neil

[Velocita Rosso]

Answers depend on how many miles you cover
Some do not bother if they are only doing a handful of miles
Some do not bother and use additive
However if the car is used regularly and on long events it may be prudent to convert

[cook1e]

Some people say just run the car and wait until the valves and seats are knackered before worryng about it as it will take a lot of miles for this to happen and chances are something else will break first.


Certainly worth doing though if you are rebuilding the Engine or replacing/rebuilding or porting the head. I had an unleaded head on a recon full Engine from John Kippings about 20 years ago, it didn't make much difference to the cost from what I remember so was well worth it.

[SveinHa]

cook1e wrote:

Some people say just run the car and wait until the valves and seats are knackered before worryng about it as it will take a lot of miles for this to happen and chances are something else will break first.

I think this is a fairly reasonable approach to the "problem". Additive is cheap so I intend to use it whenever I can but no panic if I should forget it... So far I only have less than one mile in my GT6 but that is about to change...

I recently watched an episode of Wheeler Dealers where they converted the head on a Spit to unleaded valve seats and they made big point about it claiming it would be easier to sell and for a higher price. I don't think it is that big deal but if the head for some reason is off I would convert it.

[thebrookster]

If you are planning on selling the car, then yes Wheeler Dealers were right. The average punter looking for a cheapish first time classic will be caught by things like this. Those of us who frequent forums like this one and are a bit more car savvy quickly learn it does not make much difference most of the time.

As has been said, watch for excessive seat wear, you'll easily notice it as you find yourself constantly tightening the tappets. Until then, I would not make a concerted effort into changing the seats, however if you are rebuilding the engine probably worth doing, at the very least on the basis of better safe than sorry if nothing else.

[Gt6s]

thebrookster wrote:

If you are planning on selling the car, then yes Wheeler Dealers were right. The average punter looking for a cheapish first time classic will be caught by things like this.

As has been said, watch for excessive seat wear, you'll easily notice it as you find yourself constantly tightening the tappets.

First off I would not trust a word that moron Mike Brewer said.
If you go to buy a classic car can you really trust that the unleaded conversion has actually been done ? On the other hand if seller says it has not been done you can take that to the bank.

With valve seat recession you LOOSEN the tappets.

Laurence

[Andy Flexney]

1027 wrote:

Whats the general thoughts of getting the cylinder head converted from unleaded to leaded.

I wouldn't bother I don't think it is worth it. The rumours about reintroducing leaded petrol are just that.

:) :) :)

AndyF

[Neil MAC]

Thanks for the replys I don't do that many miles 1000 -2000 a year but this year planning a big trip around
Europe.
Saw the wheeler dealers where they did the head thats one of the reasons I was after your views.
I have no plans to sell the car so any work I do or cash I spend will be to my benefit.  I haven't had to adjust the tappets other than after putting the head back on a few years ago.
Neil

[herald948]

On an original 1147cc Herald engine of mine that had already done 50k miles, I've put another 60k miles on the car. There was no indication from the previous owners of the car that any "unleaded conversion" had ever been done, and I haven't had it done, but it has run exclusively on lead-free gasoline all my 60k miles with NO additives or lead substitutes. That engine is still fine.

My point? If it ain't broke, don't fix it. On the relatively rare occasion that valve seat recession due to a lack of lead begins to develop, you can have whatever you want done to the head at that time. In the meantime, why throw away your money?  ;D

[Steve.G]

I decided to get a reconditioned head for my 2000 after finding one of the valves was burnt. I bought one form one of the larger specialists with hardened seats fitted. It turned out to be not a very good quality one and needed to be sent back to have new guides fitted as the previos one had been cracked during fitting.
I ended up getting a good used valve and re-fitting my original head. That was used for a couple of years with no apparrent ill effects.

I suppose the moral of this is don't get a cheap reconditioned head just to get hardened valve seats when the one you have is basically OK.

[Nick Jones]

On a well used engine that has been undisturbed since the days of leaded petrol I would absolutely not bother until it actually starts showing signs of trouble (tappet gaps keep closing up) - and it probably never will.  However, if you do have reason to gives the valves anything more than a very light grind-in, it probably does then become worthwhile as this will remove any existing lead memory/work hardening from the seats.

Only the exhaust seats need doing.

Nick

[thebrookster]

Gt6s wrote:

First off I would not trust a word that moron Mike Brewer said.
If you go to buy a classic car can you really trust that the unleaded conversion has actually been done ? On the other hand if seller says it has not been done you can take that to the bank.

With valve seat recession you LOOSEN the tappets.

Laurence

Laurence - I quite agree with you, I would not trust Mike Brewer either, however the point I was making in that the un-initiated can be overwhelmed with inconsequential details like this still stands.

Good point about Tappets though, it has been a long few days loading this last week, and my brain is still reeling!!

Cheers,

Phil

[piman]

Hello Neil,

one point that hasn't yet been mentioned is that the valve seat recession is far worse if the car is driven hard using a lot of revs. Driven steadily and with your annual mileage you probably will not experience any real problems for some years. In itself it does not give any improved performance, unless your valves have sunk quite deep into the head.

Alec

[ferny]

Original Herald engine was apparently converted and I got valve seat recession on it doing the RBRR. The Spitfire engine had been converted as well apparently and I had to adjust it all in Andorra on the 10CR. Probably says more about me than the engines though... Either way, if it's working fine I'd leave alone. If it's already off then you may as well drop it in for a refresh and possibly get it cleaned up so it works a bit better than out of the factory. But make sure you go somewhere with a good reputation.

thebrookster wrote:

If you are planning on selling the car, then yes Wheeler Dealers were right. The average punter looking for a cheapish first time classic will be caught by things like this. Those of us who frequent forums like this one and are a bit more car savvy quickly learn it does not make much difference most of the time.

I gave them the benefit of the doubt on that. I hope they were just covering their own arses and felt it was safer to give a broad bit of advice rather than an engine specific one just in case someone with an a series didn't bother and blamed them.

[tiggrr1]

Hi Neil,

Never bothered myself and have no valve recession problems, though I do put the odd dose of valvemaster plus in the petrol tank.

As suggested if you want peace of mind now would be the ideal time to do it if the head is off.

[Neil MAC]

Thanks for the advice

The car was running fine before winter think I will try some adative in the petrol and maybe sort the cylinder head "eventually" whenever it starts actually causing problems.
Just out of interest thougb can anyone recomend anywhere  to actually get the head done I'm in Warrington but would travel to a recommended engineer.

Neil

[Matt George]

1027 wrote:

Just out of interest thougb can anyone recomend anywhere  to actually get the head done I'm in Warrington but would travel to a recommended engineer.
Neil

Hi Neil,

Peter Burgess comes highly recommended, not a million miles away from you either.

http://www.mgcars.org.uk/peterburgess/

Matt

[oil_on_the_carpet]

1027 wrote:

Thanks for the advice

The car was running fine before winter think I will try some adative in the petrol and maybe sort the cylinder head "eventually" whenever it starts actually causing problems.
Just out of interest thougb can anyone recomend anywhere  to actually get the head done I'm in Warrington but would travel to a recommended engineer.

Neil

There was a TR250 featured in TW a while back that had done umpteen hundred thousand miles on a standard un buggered with head.