Hi all,

After hearing about so many EJ257's that have popped, then people rebuilding them with decent pistons and rods, and then having them pop again, you'd probably think they're junk and you have to spend $5k reinforcing the block with liners and close decking to make it handle power.

Well I'm not going to comment on that, but I always found it amazing that Cosworth's crate motors have a stock block, and there are plenty of NASIOC anecdotes of them making plenty of power and doing heaps of miles at the same time.. one guy claimed over 100k miles, and a few are saying they've clicked over 50-60k miles without a hiccup.

To put it simply..


Cosworth torque plate hone the blocks with Cosworth gaskets and head studs in place, and apparently the block is heated up to operating temperature too prior to honing.. once they do this, they apparently last.

This is important because the bores are out of round from the factory.

Stock bore with torque plate not torqued into place



Torque plate done up as per head stud torque settings.



Out of round by .0023!!

So, if your piston needs .003 of piston to wall clearance, you're gonna be in trouble if you hone or bore without the torque plates. Not only will it do a ring land or scuff a bore once the piston hits that tight part of the bore, but plastic deformation of the block can occur if its constantly pressed and rubbed in that tight spot by the forged piston.. and this can cause a crack.

If you're getting a 257 built, ask the workshop to torque plate hone. There is one workshop I know of that does this and they've had a lower failure rate than some of the other workshops as far as I know.

If you wanna be baller, contact Cosworth and buy their torque plates.. they sell them to engine builders (not cheap!).

So I'll leave it right there... thoughts and comments are welcome.