Jump to content


Photo

12G295 Head Valuation


  • Please log in to reply
10 replies to this topic

#1 JonnyAlpha

JonnyAlpha

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,922 posts
  • Location: North Devon
  • Local Club: Exmoor Minis

Posted 04 August 2018 - 12:52 PM

Hi,

 

I recently took my Mini to a local show and met loads of ex mini owners. One in particular used to tune minis as a young lad and has what he thinks is a standard 12G295 head.

 

Question - how much is an unmodified 12G295 head worth?

 

TVM



#2 absx2

absx2

    Speeding Along Now

  • Members
  • PipPipPipPipPip
  • 474 posts

Posted 04 August 2018 - 04:33 PM

Most 12g295 heads will have done a few miles and have badly recessed valves that will need replacing. This will be expensive using the correct short over sized valves or  expensive using 1275 valves turned down to suit. with 1275 valves you also have the agro of spacing the rocker gear to get the geometry something like correct.

Then you have to remove on average about 4 cc from the combustion chambers to get the compression ratio something like it if you have flat top pistons, more money

You will also be needing new valve guides.

Standard heads measuring 2.75" are only valuable to standard 998 cooper owners using the  D top pistons or 1100 MG owners.

So just putting you in the picture that this is probably not going to be a bolt on and go experience so 100-130 quid should be about it and the guy is a good sport rotary wire brush the chambers and check for cracks before you buy it. Then depending on the condition of the valve seats expect to spend another 100-200 on it for facing, new guides, valve seats re cut and possible new valves. 



#3 JonnyAlpha

JonnyAlpha

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,922 posts
  • Location: North Devon
  • Local Club: Exmoor Minis

Posted 04 August 2018 - 09:07 PM

So - unless I can get this cheap and be prepared to spend £100 - £200 on it it's best to let it be?

I was not going to pay more than £50 anyway, and only if I was sure it was standard.

Might be worth buying and selling on to a 998 Cooper owner?

 

I'll start a new thread but for a standard 998 what the best head option - modifying a standard 998 head? 



#4 absx2

absx2

    Speeding Along Now

  • Members
  • PipPipPipPipPip
  • 474 posts

Posted 05 August 2018 - 11:32 AM

To be fair a couple of hundred quid or so for a head ready to bolt on is very good value as performance costs money.......lots of money :)


Edited by absx2, 05 August 2018 - 11:34 AM.


#5 Mrpeanut

Mrpeanut

    One Carb Or Two?

  • TMF+ Member
  • PipPipPipPipPipPipPip
  • 1,018 posts
  • Location: Southampton
  • Local Club: Wessex MOC

Posted 07 August 2018 - 07:27 AM

I just sold a bare 295 for £110. It needed new valves, seats, the lot. Somebody will have to throw a few quid at it but will have a superb, increasingly rare, head for £300-400. Try buying a refurbished 295 off the shelf for that money.

If you want it then your £50 budget is unrealistic. The £100-130 above feels about right, assuming it's crack free.

#6 JonnyAlpha

JonnyAlpha

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,922 posts
  • Location: North Devon
  • Local Club: Exmoor Minis

Posted 07 August 2018 - 12:22 PM

I just sold a bare 295 for £110. It needed new valves, seats, the lot. Somebody will have to throw a few quid at it but will have a superb, increasingly rare, head for £300-400. Try buying a refurbished 295 off the shelf for that money.

If you want it then your £50 budget is unrealistic. The £100-130 above feels about right, assuming it's crack free.

 

I agree, but the thought of picking one up for less that £100 was tempting.

 

I have just been to look at the head, the bloke selling it wasn't there but his son let me have a look at it and says his dad wants £100, which as you say is about right. The head is complete but I will probably need to replace the valves? 

 

According to my research all the measurements look like its standard depth (I measured 72mm) and the inlet and exhaust valves are 31mm and 25mm which is also standard. I laid a metal ruler across the cyl head mating surface and it all seemed straight? The only thing I forgot to have a good check for was cracks :-(

 

Anyway (subject to it not being cracked I have offered him £75.

 

Shw1RLs.jpg

 

OHWyURU.jpg

 

 

jy6pCwB.jpg

 

dsle1zb.jpg

 

eEDFk5a.jpg

 

In the last pic I tried to measure the depth of the oil gallery but I am not sure if this is the correct hole. It measured around 16mm.



#7 JonnyAlpha

JonnyAlpha

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,922 posts
  • Location: North Devon
  • Local Club: Exmoor Minis

Posted 07 August 2018 - 07:50 PM

OK so I need some advice, subject to a further inspection the guy has accepted my offer of £75 for the head, he also mentioned though that he had tapped (hit) the rockers and a couple are stuck. Is this normal (well not normal but acceptable for an old head that will be refurbished). I guess there is some corrosion in the valve guide that should be freeable?

 

Advice on purchasing please :-)



#8 Retroman

Retroman

    One Carb Or Two?

  • Traders
  • PipPipPipPipPipPipPip
  • 953 posts
  • Location: Sunny Sabden
  • Local Club: CDMC

Posted 07 August 2018 - 08:28 PM

At 75 quid if you don't want it I will have it...its VGVFM at that and will need new guides and the seats re-cutting.

 

Ideally should have hard seats fitted to the exhaust so you can run unleaded.

 

It needs stripping to be sure but the inlet valves are probably OK, the exhausts are the ones that suffer most, and I would renew them.

 

The oil hole is the small one in the corner, it won't be an issue.

 

pm me for a price on the guides and valves.



#9 JonnyAlpha

JonnyAlpha

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,922 posts
  • Location: North Devon
  • Local Club: Exmoor Minis

Posted 08 August 2018 - 08:42 PM

At 75 quid if you don't want it I will have it...its VGVFM at that and will need new guides and the seats re-cutting.

 

Ideally should have hard seats fitted to the exhaust so you can run unleaded.

 

It needs stripping to be sure but the inlet valves are probably OK, the exhausts are the ones that suffer most, and I would renew them.

 

The oil hole is the small one in the corner, it won't be an issue.

 

pm me for a price on the guides and valves.

Sent



#10 JonnyAlpha

JonnyAlpha

    Camshaft & Stage Two Head

  • TMF+ Member
  • PipPipPipPipPipPipPipPip
  • 1,922 posts
  • Location: North Devon
  • Local Club: Exmoor Minis

Posted 08 August 2018 - 08:47 PM

Picked up the head today. £75. Cleaned up the areas between the valves where I couldn't see before and I cannot see any cracks, the gentleman even said if it turned out to be naff he would refund me :-)

 

I'll close the post now and continue for the time being on the other thread here:

 

http://www.theminifo...head-valuation/

 

and then start up my project thread again. 



#11 mk3 Cooper S

mk3 Cooper S

    Crazy About Mini's

  • Members
  • PipPipPipPipPipPipPipPipPipPip
  • 5,569 posts

Posted 08 August 2018 - 09:18 PM

Good value at that price.  I thought it was the early S heads that cracked readily? not cooper ones.






0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users

Mini Spares