I posted a thread last year but Wiseco seems to have updated their catalog and changed specs on these pistons. I have yet to start my motor build due to time.
Specs:
2.4l block
Manley 150mm h beams
Stock 2.4 crank

Pistons are k656m87



Wiseco Spec sheet. Some of these numbers seem off only for those pistons. And google searching shows sellars of these pistons but no one actually using them.

 

Those are wrong. You will be at 14.25:1 compression.

You should get the K626M87. However, the original spec sheet is wrong. Compression will be around 10.6:1 using a stock head gasket with those pistons and evo 8/9 head.

I am running the JE proseal thick gasket to bring compression down to 10:1 and I have some combustion chamber work done that lowers it a little more.

Also, Do yourself a favor and get some I beams. Those H beams are slightly stronger than stock.

 

 

Don't mean to thread jack....i also need some answers on this.
This is what i got on RSR Static Compression Ratio Calculator. Im using Wiseco K627M855AP. It doesn't look right to me at all.
Im looking for 10.0:1 CR since I plan on running pump 90% of the time and E85 10% of the time.
The Wiseco Info Sheet shows the pistons being 9.15:1 so do i need thinner or thicker hear gasket? What size?
Any help would be awesome, Thanks everyone in advance.

This is what i plan on running.
2.0 block
Manley "TT" Billet Crank 100mm
Manley "TT" I-Beam Rods 150mm
Cosworth Size 1 Rod & Main Bearings
Cosworth Thrust Bearing
Cosworth 1.3mm head gasket.

 

bump

 

any trolls willing to help with this.....lol...thanx

 

Probably not gonna see light on this.

 

You entered a negative number in the deck clearance. You only enter a negative number if the piston comes up past the deck height. In this case, the piston is .3 into the block. Hope that makes sense.

Static Compression Ratio: 8.84

Deck Height

Move piston to TDC, and measure the distance between the flat top surface of the piston (not the top of a dome or the bottom of a valve relief) and the top of the cylinder. Enter a negative number if the piston's flat surface sticks up past the top of the cylinder. At TDC the piston will "rock" so be careful in your measurements. ORCAs are .035".