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rocklord

Block and Piston Specs for AU Engine Needed

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I'm in an Information gathering mode for my AU 4.0 engine and need some values to calculate the compression ratio if I install the Tickford 94DT head.

 

I found a vendor in the USA (Silvolite) that sells pistons for the Australian 4.0.

I've attached a shot of the catalog listing for the 4.0 pistons Silvolite sells.

Looking at the piston specifications, the compression height for the 4.0 models varies from 1.208" to 1.394"

Three of the pistons identify what engines they go to:

Silvolite 3324H - EB-ED 4.0 (CH 1.375");

Silvolite 3325H & 3326H - EF-EL 4.0 (CH 1.375" & 1.394" respectively).  Is the 3326H piston with CH 1.394" for LPG?

One of the pistons, Silvolite 3333H, is domed with four valve reliefs, so it must be for the BA 4.0 with LPG (CH 1.215").

 

The last piston in the list, Silvolite 3334HC, has a single valve relief but only a CH of 1.208".

Is the Silvolite 3334HC piston for the AU 4.0?

Is the compression height for the AU 4.0 piston 1.208"?  If not, what is the stock CH of the AU 4.0 piston?

And what is the recess volume of the stock AU piston?

 

The other question I have is the stock AU block, or deck height.

Doing a search of the forum I came up with a post stating that the deck height is "somewhere" around 9.2-inches.

Another website stated the deck height as 9.22-inches.

I don't have access to local (Australian) reference material so I can't look it up.

So I'm wondering what the stock deck height of the AU block is?

 

If I assume a piston CH of 1.208, a rod length of 6.057, a crank throw of 1.955 (3.91 stroke divided by 2) and a zero piston recess, then the deck height would be 9.22-inches. 

If any of my assumptions are wrong, then....

 

Any help is appreciated.

post-1604-0-31127700-1478185282_thumb.jpg

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Maybe they use them in their generators Dave, wasn't it you who found they were using barra's for generators? There was a link to a website on here somewhere where they were advertising them as such, was pretty interesting but no idea where the link is

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Yes in the US, the Barra is listed as a industral engine,

 

http://www.aclperformance.com.au/EU/Ford4.0LIntechCastPistons.htm

ACL AU pistons were 1.219" comp height,

 

http://www.precisionintl.com/Engine.aspx?ID=470&EID=11716

Hypertec AU piston is 30.9mm comp height, have 4.4cc dish (3rd down)

 

Not sure on AU block deck height but X-Flow is around 9.44" with around 0.020-0.030" piston to deck clearance,

I know the SOHC engines run smaller deck clearance, say 0.010"-0.020"

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