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Can anyone tell me what the VE is of a ea81 engine stock?

thanks in advance.

The Subaru EA-81 engine was produced from 1980 to 1989 and is a stroked version of the EA-71.

Specifications

Displacement: 1,781 cc
Bore: 92 mm
Stroke: 67 mm
Compression Ratio: 8.7:1
Valvetrain: OHV Pushrod
Horsepower: 73 bhp (54 kW; 74 PS) at 4,800 rpm
Torque: 94 lb·ft (127 N·m) at 2,400 rpm

any help there?

OR HERE

http://www.ajdesigner.com/phpengine/eng ... ciency.php

TOONGA

Gidday Jules. long time no hear.

The reason for the VE is a friend told me that to install a supercharger (SC12) its handy to know your VE of your engine to more accurately calculate boost.

He claims that if I calculate boost at 6psi then I could be running say 10psi due to VE.

So thanks anyway but cant use that calculator - wouldnt know cfm etc.

google cfm of the hitachi ?

hitachi cfm = 130 -150 .... thats for a 28/32 and i think thats what the ea's come with?

thanks guys.

so typed in my values into that calculator on Toongas link of

150
108 c.i (1781cc)
6000 rpm

result .79. I assume thats 79% VE. Not bad.

I'm an old fart. Cant remember why I asked for it in the first place.

Oh yeh. This figure should, according to a mate) give me an idea of its breathing efficiency. It would determine at an indicated 6psi that it would be likely real boost would be 21% higher say 7.5psi. if that makes sense. So seeking 5-6psi perhaps my pulley sizes should mean calculations to focu on say 4psi.

My maths tell me that 1:1 on pulleys on the ea81 is 6psi. So a slightyl larger pulley on the SC might be the way to go. Can always try 1:1 to start with.

good stuff.