Right then. Further to my previous question over piston choice I need some more advice.
I'm building a forged 86mm bore Zetec bottom end for ZVH use. I'm sticking with ZVH as I have a well specc'd head modified to use a Zetec headgasket, and good inlet set up so want to keep costs down slightly and use what I have as I have already spent £360 on a brand new Newman Cam and lifters.

Now the problems.

I have a set of Accrilite Forged pistons in my existing bottom end, and a set of early Mahle C20XE forged pistons. I've been told to use the XE pistons but I would like to know what rods are best to use with these and what sort of CR I'd be looking at?

The Accrilite pistons I'm unsure if/how much they have been machined. But at TDC they sit about 3mm below the deck height. I will measure this wednesday and get a more accurate measure.

Eagle rods seem cheap to import but I'm told they are longer than standard rods so throw the CR out?

I how ZVH, becuase of the combustion area being bigger in the head can get away with running what would be slightly too high in a Zetec Turbo. Can anyone shed some light here? Most of the info is ZT based.

 

standard rods are fine up to around 300 bhp at 8:1 cr or lower imo

 

Problem is I've got a straight cut Quafie gearbox which is going to rev them very hard = failure

 

i believe there is more capacity in the dome of the cvh head, about 15cc or there abouts, therefore xe pistons will give a 8.1:1 CR IIRC

the mahles will be alright and the rods will probably be alright till 300bhp, or slightly over as i've been informed.
to make the bottom end the best then, steel rods and forged pistons would be the best route with a cr of what you want, rather than a mis-mash of parts.
eagle rods are a bit longer than standard as they are designed to be used with pistons where the gudgeon pin is higher in the piston to reduce teh angle of the rod inrelation to vertical, this makes it able to handle more stress as there is less lateral (side) force.