Cylinder Sleeves

[wraith]

Just a question to the more engineering types (stu?). Is it possible / practical to have cylinder sleeves protruding from the block, with a matching recess in the head?

Cheers,
Ash

[jezza323]

i would imagine it would make sealing with a headgasket a bit of a problem

also would think thermal expansion of the sleeves at a different rate to the (presumably aluminium) head could cause some headaches...

[wraith]

I was working on the theory that the headgasket would become a moot point. As for expansion, if theres an issue, wouldn't it be apparent in an alloy block? I guess what I'm thinking is putting most of the combustion chamber within the iron sleeve, thus improving cylinder strength. I realize there must be some issue- otherwise it'd be a done thing.

cheers

Ash

[oldcorollas]

there are cylinder/cylinder heads made in a single piece, then bolted to crank case, to avoid the issues with headgaskets...
but it makes for difficult and more expensive machining.

[wraith]

hmm. If memory serves me correctly, don't the old VW engines have sleeves that protrude into the head?

Ash

[o_man_ra23]

The cylinder could get in the way of valves if the valves are at an extreme angle and the sleeves protrude by a large amount.

Sounds pretty crazy, but I can see your reasoning. O-ringing the block is done for a similar reason, perhaps you should just oring the block and head and use a copper head gasket??

Cheers, Owen

[30psi 4agte]

F1 use to use sulphur rings which would sit half in the head and half in the block (sort of like a o-ring recess) to achieve a strong seal in their high boost / rpm engines in the 80's

[Aust162]

I think old iron block motor's use to have iron sleeves fitted? In an alloy head on a car engine i dont know how that would go?

On motorbike engine's its quite common to have an iron sleeve in an alloy head, but iron doesnt dissipate heat aswell. Overheating issues in these cases are quite common.

As for having the sleeve coming above the deck, i would agree with the others above ^^.valve clearance and head gasket sealing issues.

[o_man_ra23]

I think old iron block motor's use to have iron sleeves fitted?

Not quite, often iron block engines from the old days were unsleeved. Some Jappa blocks were, but Aus/Seppo blocks were just reliant on the casting material. Hence why Hole-den/Fraud blocks need reboring every couple of hundred thou, but Jap blocks only need it if something catastrophic has happened, or there is close to a million k's. Pity the rings/pistons dont last that long.

I still think o-ringing will produce the results you are after.

Cheers, Owen

[tricky]

I still think o-ringing will produce the results you are after.

Agreed. Your suggestion sounds feasible, but probably uneccessary and very difficult to actually get right. I think sealing it properly would actually be quite difficult (if the image in my head is what you are trying to paint, that is).