2.7 eta again

[mattG]

sorry guys have read and searched for days

have got the chance to get a 525e cheap of a mate

so

why a 2.0 and not a 2.5 head on the eta bottom end
what power should this make

or

eta crank 2.0 rods in a 2.5 block is that right
what power does this make

[maxfield]

Is it to do with the shape of the piston with a 2.5 head the pistons would hit the head.

[Templ8e30]

Nope, an eta head has the same combustion chambers as a 320i head but the 320i head has bigger ports. Fit a 320i head with 325i cam/manifolds/injectors etc to a 525e bottom end and you'll get about 180/190bhp.

Another way is to fit the 325i head to the eta bottom end, this will give lower compression but has bigger valves than the eta or 320i head and should liberate more power but less torque.

The best way is 325i/525e block (they're the same), 525e crank, any non-325i M20 conrods (320i/323i/525e etc all use the same conrods), late 325i pistons (early ones need machining) and a 325i head. The block will need some machining off the top to match, this will give the best power but is obviously more involved and costly.

A 320i head cannot be used with 325i pistons because the pistons will clash with the head and it won't even turn over.

Cheers,

Iain T

[mattG]

cheers Iain

am thinking of the FI route,

so eta bottom end as is & fit 2.5 head what whould the compression be?

[Ant]

Too high Matt , that is the Spec Erel had remember...... H/Gasket almost weekly

I can build a low CR 2.7 for ya mate

[mattG]

so
eta crank & rods late pistons deck the block (either eta & b25 the same) to what ever i want the compression to be,

[oze30]

Matt.. i got all you need for high comp or low comp 2.7. Pm for details