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5K Head, What'S This?

Featured Replies

Hey folks,

 

Just got hold of a 5K for rebuild (thanks SLO-030).

 

Having a look over the head, and it has a stud in it that points down into the lifter gallery.

 

Just wondering, can anyone tell me what it's for?

 

Cheers

 

Mike

post-3479-085112500 1287566256_thumb.jpg

Edited by snot35

It doesn't appear to drop into the lifter gallery. Is there a hole in the block for it to fit into? If so it's most likely a locating lug.

Also that head has been faced to within an 1/8th of an inch of it's life.

Edited by GJM85

It doesn't appear to drop into the lifter gallery. Is there a hole in the block for it to fit into? If so it's most likely a locating lug.

Also that head has been faced to within an 1/8th of an inch of it's life.

 

:huh: explain how?

It's a locating lug.

Most heads have had this removed.

  • Author

I don't quite get that so far. It's a lug, but it has a thread? When I mated the head to the block it didn't locate to anything, it just fell into an empty area in the block where the lifters are, not locating anything at all.

 

Has it been surfaced that much, i.e. is it knackered??

 

Please say no! :)

  • Author

Just for clarity, this appears to be a 5K head. It has the lugs on 1 and 4 and came with a D dish piston block.

It's all good.

Yeah it's a 5k head D piston type/ shallow combustion chamber type.

If i remember rightly there's a hole in the gasket for it!!

:huh: explain how?

 

That small half circle above the lug 'pictured' is a wear mark. The 4k and 5k heads i've got have a much deeper mark. And that head has not got much life left in it.

Edited by GJM85

ah i see!

 

hey maa i learnt something today!

ah i see!

 

hey maa i learnt something today!

 

Well so you do know, pushrod length becomes an issue at that late stage as does compression and valve clearence. When old mmate puts this thing together he'd want to be looking for another head....

  • Author

What sort of depth does it have normally?

 

And I guess this is a good segway into planning what to do with this block. I have most bits, but I don't have any lifters, so it will need some sort of conversion. This opens me to getting O dish pistons and maybe putting a 4K head on it? But then I need to work out push rod lengths. Does anyone have any advice on that topic regarding which direction to head? :)

 

I was planning to bump the compression up to around 9.8 to 10.

 

Cheers

Couldn't be sure but i'd say around 5 or 6mm on my heads.

Buy a ACL rebuild kit to suit shallow dish pistons and get a 4k-5k head without lugs. You'll need to check the crank sizes to get the right size bearings. Check the bore in the block to see if you'll need oversize pistons. Source your lifters, pushrods and rocker gear. Then get your cam ground to suit.

 

Start reading the FAQ. It's a good starting point. I'd be happy to help with any questions or advice though there are many far superior to I.

Edited by GJM85

  • Author

Yikes, this would be around 1mm deep. It seems like a lot to have taken off of the head. Anyone know the cc for one of these heads? I get around 16-17cc

 

I've read through the faq quite a few times. Thank you for the offer of help. It's a shame if I can't use this head, the port shape is soooo much nicer than that of the 3k's that I have. Is the 4k head any better??

  • Author

Thanks for your help folks! Very much appreciated.

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