260 deck height/squish

[apar]

If I have understood correctly 260 block is about 0,04" higher than 200 2.5L block.
Because of that it should have quite big squish height than "normal 2.5" 200 gasket head block.
Or am i missing something.

The reason i am trying to figure this out, is that i have 200xs gen2 optimax o-ring block (also 0.044" higher block) that i'm going to use with gasket heads.
200xs gen2 block have LL stamp in it.

Pistons are flat vertex, and heads that i'm going to use are 18789-c3. I'll cut them to get around 150psi compression pressure.

Could i use 260 gaskets, then i should have same squish than 260 motor (does it really have so big squish height 2,00mm?).
Or would it be more reasonable to lower the deck, and get the squish to 1-1,2mm total.

[FORBESAUTO]

You need to deck the block of a o-ring block to run gasket heads to get correct squish. I like to run zero deck height, that way your squish will be around 0.35 ( thickness of compressed head gasket) depending on head gaskets you use. The oring head sits dead on block so they have to add squish by raising deck, if you run gasket you'll roughly get twice the squish needed.

[apar]

Lowering the deck is propably the way im going to do this.
But is the 260 piston 0.04" lower than deck at TDC?

[FORBESAUTO]

They are usually even or sticking out slightly, deck is usually shorter than 200

[dwilfong]

O ring heads will transfer heat better and do not blow out as easy. you can get the o ring heads cut and the groves machined in them .
Also make it easy to pull the heads and check things out. Get a set of dorman studs so you don't have to thread in and out of the block all the time.It is worth the little extra to do it.
Then again may be cheaper than decking the block.

[Chaz]

If I have understood correctly 260 block is about 0,04" higher than 200 2.5L block.
Because of that it should have quite big squish height than "normal 2.5" 200 gasket head block.
Or am i missing something.

The reason i am trying to figure this out, is that i have 200xs gen2 optimax o-ring block (also 0.044" higher block) that i'm going to use with gasket heads.
200xs gen2 block have LL stamp in it.

Yes , the thing your missing is an accurate measurement .
Easy to fix , you can buy , or as I have done with a drop of scrap of aluminum. You can carve out your own height mike bridge . The $20 dollar gauges are pretty repeatable , have a in/mm button so you can work with what your use to and a sharpened 3/32" aluminum TIG wire makes a good pointer .
The good guys measure the four outside corners and correct the ski slope factory deck numbers regardless of which parts they use for their builds ..

[apar]

I have measured with feeler gauge, so know for sure that my pistons are 0.044 lower.



But the thing that i am confused about, is the mixed info of the 260 block height and that squish.

[FORBESAUTO]

They are saying the piston is 4 thousands below deck and the drag is 4 above. Yours is 44 thousands below.

[apar]

That solves it. I was pretty sure that i was missing something
thank you for clarifying my stupid question.

[W2F a V-King]

O ring heads will transfer heat better and do not blow out as easy. you can get the o ring heads cut and the groves machined in them .
Also make it easy to pull the heads and check things out. Get a set of dorman studs so you don't have to thread in and out of the block all the time.It is worth the little extra to do it.
Then again may be cheaper than decking the block.

Do you recall the part# for those doorman studs?
Thank You.

[dwilfong]

#675-006 studs but you need to cut some off the long end. This way it treads all the way in to the block and stops at the shoulder.
Get them from Rock auto only a buck or so each.

[Chaz]

Don't get good stainless hardware ....
Get the cheapie black one's ... they'll start turning nice and orange by Halloween ..