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jack brashear

A14 engine piston tops are a little above the block surface. Is this normal?

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The original A14 piston tops are about 0.012" above the block surface. The cylinder head appears to be slightly relieved to accommodate this but the little metal ring around each cylinder of the head gasket appears to interfere very slightly with the piston tops. There has been no machining at all. All components are stock and original.  Do I have a problem here? What should I do?  This engine and a 3N71B auto are going in my Morris Minor.  Also I just don't want to use the stock boat anchor exhaust manifold.  Any header suggestions would be greatly appreciated.  Thanks.

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Completely fine. Even with a closed chamber head with lots of quench area there is still the thickness of the crushed head gasket (about 1.2mm) between the head and the block. Generally it's not a good idea to exceed 0.3mm above the block, to allow for rod stretch at high RPMs.

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Are you sure you have an A14 head gasket? The ring on the gasket should be a slightly larger diameter than the bore. The A12 gaskets are right on 76mm versus 77.5 thereabouts for the A14/15 gasket.

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seems like the head gaskets available on-line don't show a difference between A12 and A14 engines.  How can I be sure of getting one for an A14 engine? I've been doing well on British engines for decades and I've not seen this situation before,  By the way, this A14 engine is a superb piece of good work superior to the old Brit iron in my humble opinion. What's a guy to do??  All feedback is appreciated.

Jack

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Jack go to Rockauto, use a 1981 210 for the vehicle and order a Fel-Pro gasket for an A15. Should be Fel-Pro 21199. 

 

What at bore does your motor have? Standard is bore 76mm, the 21199 gasket bore is 77.50mm (I measured)

 

While a BMC A-series is a great motor the Datsun a12/14/15 are indeed more robust being 5 main bearing motors.

 

I have a bare A14/A15 block if you take a measurement from the deck to a fixed point on the block I may be able to compare it to mine and we can see if the block has a lot taken of the deck. The machine shop for my race motors lightly skims the deck and the pistons are never proud of the block.

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Tom 1200, thanks for the info, I really appreciate it.  I phoned DNJ (the gasket set supplier I used)and was told that their packer probably put the A12 head gasket in the set by mistake.  Anyway, I expect to get the A14-A15 gasket in a few days.  Hoping that will work!!

Jack

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The only A series headers I have ever used were from the guy who built them for Nissan Motorsports, and they were vehicle specific. It wouldn't be that hard to fab up a nice stainless header to fit the Morris Minor.

 

Some of the older A series cast iron manifolds were pretty nice, but I am not positive that all A series have the same bolt pattern at the flange.

 

For the record, I loved the 1275 I built for my Sprite. It was all BMC and made over 100 HP, but was also very streetable. I would never have swapped it out for an A series. It did have a PHH44 Mikuni on soft mounts, a custom header, large valves, big cam, etc... So maybe it wasn't all BMC.

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I RECENTLY SOLD MY '62 MK2 SPRITE WHICH I HAND BUILT OVER 30+ YEARS.  WAY TOO MANY MODS TO TYPE ABOUT HERE BUT IT DID HAVE A 5-SPEED AND A 3.7 REAR PLUS MANY, MANY OTHERS  SHE WAS A 1275 WITH A SINGLE HIF 6.  WONDERFUL LITTLE CAR BUT AT AGE 76 IT WAS TOUGH GETTING IN AND OUT.  SO NOW I TAKE COMFORT IN MY '62 3000 MK2 WHICH I BOUGHT NEW IN MAY 1963.  I CAN TALK ABOUT THIS UNTIL THE COWS COME HOME SO FEEL FREE TO CONTACT ME AND WE CAN EXCHANGE PHONE NUMBERS.  I LIVE IN CENTRAL ARKANSAS.

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 Try Ariel font size 14 and not all capital lettering.

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Ah c'mon Mike.....that was the one post I COULD read without my bifocals.

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If we are all standardized you can set your Ctrl + to comfortable viewing. (but I hear ya) I got a 27" gamer monitor last year and I have a parts catalogue running on my other computer but you can't adjust the size so I have a 31" Sony flat screen for that.

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