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Brown Clubman
 Post subject: re-bore or hone?
PostPosted: Fri Oct 31, 2008 9:21 pm 
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How does one come to this decission?

I've recently purchased a 1275 for my rebuild that I'm told is +20thou. The bores look to be in pretty good condition with a very slight lip and previous hone markings still present.

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I like the idea of keeping it at 1293 but reality is it will probably need a re-bore.

Is it just a matter of asking someone in the know to have a look and advise?

Cheers,
BC.
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aaron
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PostPosted: Fri Oct 31, 2008 9:25 pm 
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id go the bore, not much more and it'll give you a much better motor in the long run. do it once do it properly i say.

Cheers
Aaron

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drmini in aust
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PostPosted: Fri Oct 31, 2008 9:31 pm 
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You can see the wear at the top of ring travel, a hone won't remove that.
You will probably find a new set of rings for your old pistons are the wrong side of $100. They won't work well or last long with that wear there.

It needs a rebore and hone to 1310, then you will get nice straight round bores with the right piston clearance. :wink:
A set of +.040" Hypatec pistons and Hastings rings is only around $170.
UK `AE Hepolite' ones are dearer, but no better.

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Mick
 Post subject:
PostPosted: Fri Oct 31, 2008 9:38 pm 
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Location: Under the bonnet son!
Did the GT block come with any other goodies?

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Brown Clubman
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PostPosted: Fri Oct 31, 2008 9:38 pm 
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drmini in aust wrote:
You can see the wear at the top of ring travel, a hone won't remove that.
You will probably find a new set of rings for your old pistons are the wrong side of $100. They won't work well or last long with that wear there.

It needs a rebore and hone to 1310, then you will get nice straight round bores with the right piston clearance. :wink:
A set of +.040" Hypatec pistons and Hastings rings is only around $170.
UK `AE Hepolite' ones are dearer, but no better.


Thanks guys. Sounds like a rebore is definitely the way to go.

appreciate the comments.

Think I'll go with a GR RE13 too :wink:
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BALLISTIC
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PostPosted: Fri Oct 31, 2008 10:25 pm 
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:) You can get +30 pistons so it will be a 1300cc (thats what mine is).
:roll: I know there is no subsitute for (in this case) cubic centremeters :D

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Brown Clubman
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PostPosted: Fri Oct 31, 2008 10:40 pm 
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Mick wrote:
Did the GT block come with any other goodies?


unfortunately not mick... crank would've been nice!

Scott - so size really does matter?? :lol:
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Klubman
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PostPosted: Fri Oct 31, 2008 10:44 pm 
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If it is already +20, will +30 be enough to clean it up? I'm no mechanic but as a machinist I would have thought +40 would be easier to achieve an that +30 would be a bit tight.

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BALLISTIC
 Post subject:
PostPosted: Fri Oct 31, 2008 11:05 pm 
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Brown Clubman wrote:
Mick wrote:
Did the GT block come with any other goodies?


unfortunately not mick... crank would've been nice!


What crank do you need :?:

Brown Clubman wrote:
Scott - so size really does matter?? :lol:


It has is place BC :wink:
If you are not worried about doing another rebuild on it you may as well go straight to +60

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Brown Clubman
 Post subject:
PostPosted: Fri Oct 31, 2008 11:41 pm 
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BALLISTIC wrote:
What crank do you need :?:


GT or mkII S would be nice!!

BALLISTIC wrote:
If you are not worried about doing another rebuild on it you may as well go straight to +60


nah wanna keep this block for as long as possible - hence the question about honing v's reboring. If I was gunna go BIG I'd just rebuild the 1100s block that's already in the car.
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BALLISTIC
 Post subject:
PostPosted: Fri Oct 31, 2008 11:51 pm 
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Brown Clubman wrote:
BALLISTIC wrote:
What crank do you need :?:

GT or mkII S would be nice!!
BALLISTIC wrote:
.
will have a look see :)

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drmini in aust
 Post subject:
PostPosted: Sat Nov 01, 2008 6:00 am 
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That block might clean up at +.030" but I wouldn't bet on it. Safer to go to +.040", IMO.
Still are 4 rebores available after 1310, (ignoring the 74.7mm maybe possible size). :lol:

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TheMiniMan
 Post subject:
PostPosted: Sat Nov 01, 2008 3:04 pm 
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Just check the block isn`t sleaved first,,, :-)

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Brown Clubman
 Post subject:
PostPosted: Thu Nov 06, 2008 7:23 am 
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TheMiniMan wrote:
Just check the block isn`t sleaved first,,, :-)


how would I do that? It doesn't look like it has been .... :?
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