Hi,
My 12g295 head is finally ready to be picked up from being reconditioned, so i can start puting the engine together.
This may seem like a strange question but i have two 998's to choose from to use, as i dont know the history of either, how do i work out which is best to use? and if the better one still needs a rebuild?
Any tips would be helpful
Thanks
Mark

Measuring the amount of piston slap in each engine is a good place to start

Pull the crank and bearings out and check how knackered they are, measure each crank and see which one has more meat on it. Also check if either has already been bored oversize from a previous rebuild.

Is the engine straight out of a car or has it been sitting on the garage floor for some time?

If it's the latter then definately rebuild! You're asking for trouble by wacking that new head onto an old "unknown" engine and firing it up if you ask me!

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Lillee - 1969 Morris Mini K

For sure. Don't waste your time on unknown engines, at least do the rings and bearings. (otherwise don't grace it with a 295 )

never put a new head on a tired bottom end.. give it a few weeks before shes bellowing smoke from her lil ass.. rings wont be able to handle all the new found compression of a well sealed recoed head, change the rings and the bearing wont cope with the new found power of a clean tight chamber

do the rings a bearing atleast.. give it a good hone to make sure the new rings have something to wear in with.. dont neccisarily have to go the whole hog with machine work (ask any backyard mechanic).. but a freshen is a must

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Expert in training

thanks very much guys,
As u would have already worked out my mechanical knowledge is limited,
Guessing my next step would be to remove the existing heads off the engines and visualy check which looks to be in best condition, then measure size of pistons to see if have been bored out or if standard 998 rings and baerings are required? I asume all sizes would be in my workshop manual?

Thanks

Nope, often workshop manuals only show 10 and 20 thou. The pistons should have the oversize written on the top - .512 for instance which is 20 thou (I think?). Try to rock the pistons, if they move side to side that is a good indication not to use that motor.

You need to look for scored/scuffed bores, oval bores etc...

you have said nothing about gearboxes....do both 998 have boxes attached?? do you know how well either of them drive??

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"Show me the Mini!"

yeah i thought about the gearbox last night, i'm gunna try have a good look at them this weekend, both engines are still in cars so i might have a play with the gears before taking them out.

When i picked up the head yesterday, i was chatting with the bloke and he was telling about a mini motor he was doin up for bloke to run NOS!!!
he said they were spending $8000 on a already turboed engine!!

Yeah, but if I had the spare cash, I'd do it too

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Too many cars, and too little time.