Dmacnz

Hi Guys,

Im after some "limits" question for a older Ej20G style block with thrust bearing in the #3 position.

I have recently Rebuild my Ej20G With Mahle (powerpak)Pistons, Eagle rods, ACL bearings, ARP studs, STI V4 heads and a recon Ej20K crank. The block has also be "pinned" to make semi closed.
My plan was to run about 400hp with a high (ish) rev limit.

My engine builder has now advised me that 400hp is too much and don't rev above 7000rpm. I am struggling to find any reason I should have this "low" limit. I have a 12mm oil pump installed as well.

Anyone have any idea on the limit of this kind of set up?! Is thrust at #3 really that poor of a design?!


Thanks
Dan

merlin24

iTrader: (1)

Hi Dan,
Center thrust block/bearings will take 400 brake without any problems - last one I built is running 480 brake/450 torque with ease.

A few things I would query though,
* What is your high(ish) rev limit as this is normally the limiting factor with the standard 2 piece valves and springs and the rod bolts.

* What is your reason for using a 12mm oil pump ? Unless the engine is being built with bearing clearances on the 'loose side' for a better oil film and cooling and running bore squirter's/AVCS heads/oil cooler etc etc, I wouldnt use a larger oil pump as this just creates excessive heat in the oil system due to the excess pressure constantly being dumped via the relief valve.

* the recon EJ20K crank - have the journals just been micro polished or has it been ground to over size ?

Mick

Dmacnz

I would like to rev to 7500! But my heads won't like it I'm guessing!

I put in a 12mm pump as at the time I thought it wouldn't hurt! Also the tolerances i expected from my rebuild shop wasn't expected to be perfect! (Living in china!)

The Crank was just polished, not ground. Standard sized ACl bearings were used!

Thanks for the help merlin!