Hey doc, I reckon youd be a shitload safer just chilling the inserts in Dry Ice(Co2). Using liquid nitrogen can make them bloody brittle if yer not careful. they might not be quite as tight, but they will still give ya a good interference fit.

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"He's always been a dickhead, He always is a dickhead, He will always be a dickhead. So stop complaining when he acts like one."

Yeah if I do them myself I WILL use dry ice.
But toolmakers have this dude who visits with a liquid N2 truck... so he used him
Interference fit was only 3 or 4 thou. He warmed the head up, too.
I don't believe in pressing them in, or bashing 'em...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I am running Mobile 8000 with flashlube and it's fantastic... I will try BP Ultimate next and report back...

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Lillee - 1969 Morris Mini K

I use Mobil 8000 in the Trueno.......

Afer having used all the others, it gives the best mileage

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[Maverick] 1971 Mini K

I never use SHELL OPTIMAX, from past experiences i have found that it "GOES OFF" (meaning basically, less effective) in a steel tank if it sits for any length of time! that has been my experience with the stuff!

oh yeah i usually use synergy 8000 or BP Premium!

Rohan

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1964 MORRIS 850 - POST ZOMBIE APOCALYPSE CAFE RACER INSPIRED.

https://spotify.link/D0P4KtIP2yb

1098 +0.40
266 Kent Cam
GR Flat top pistons
HS6
1.3:1 Roller tip rockers
Stupid high CR

Someone I know bent a valve and a pushrod after fitting K Lines. NOT saying they were the cause, under investigation, but the engine had been very reliable before that.

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"Show me the Mini!"

My mate is one of those guys. I went with him to a truck workshop and we dropped new cylinder sleeves into big refigerator truck...it was pretty cool.

As long as you get them to slide in right the first time you don't generally have any problems. I wouldn't worry about it making them too brittle unless you dropped 'em.

N2(l) is pretty cool stuff. Pour some in your mates stubby cooler and watch their beer freeze --- frozen foam spews out the top. Only do it to VB tinnies though.


dewey

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dwightgunning.com

optimax for me with valve master

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lookin for another clubby

people told me optimax was good mainly for fuel injected engines.
it shouldnt be used for motorbikes or carbies
due to its rather high density (heavier, harder to evapourate)

i switched over to BP ulitmate and it starts almost first time round.

i havent tried Mobil 8000 will try soon

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Inconspicuously Conspicuous
Appreciation without Depreciation
forever chasing clearer skies...

The engineering firm that I use usually just K line the old valve guides, and then bore them to suit the old valves. So you can take up a little wear on the old valves......But I was most uninpressed as I put brand new guides AND valves in this head, the they went and K lined them anyway

They said they were so used to just k lining every head that came though the door, that they didn't give mine a second thought

Managed to get some money off the job anyway.....souldn't complain. I will never need to touch it again

Minimad

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You can take the boy out of the racer.........but not the racer out of the boy!

Dunno about K-liners, but I've found the MiniSpares bronze guides do close up a bit after fitting and running. I had one grab an exhaust valve on mine, very gently.. just enought to start a burn mark on the valve.
Cast iron guides go straight in with new valves, no reaming, no worries- but I now always ream bronze guides after fitting. Even though the valves will (just) fit in without it.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

All fuel starts losing its RON as soon as it leaves the refinery.

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"Show me the Mini!"

Hey Doc, just out of interest, how much clearance do you ream in?? and any change for a racing head?

The suspician is that a K Line nipped the valve but as I said under investigation.

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"Show me the Mini!"

Clearance is in the valve stems, which are always made slightly U/S.
I use a 9/32" solid reamer.

I've run it to 8,000 a few times since around Wakefield Pk- no worries...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Flashlube = one millilitre per litre

Mini Fuel Tank, 5.5 Gallons/24.97 Litres

Therefore, half 50ml bottle is about right!!

clever aye!!

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"Show me the Mini!"