OST and JE Piston collaborate - New piston!

[oldeskewltoy]

harkes Wrote:Hi Dan

This area look like a hotspot to me. Will this not cause problems with detonation?

OST Wrote:I spoke to a few people about this and it might be an issue. I then spoke to JE and for JE Piston to set up the mill to "clip" those 4 corners(2 tiny peaks on the intake side similar to 2 on the exhaust side) on each piston would add over $200 to the price of a set... now the good news your machinist can do it prior to install!



The loss to the crown volume is about 1/10 of a cc total for all 4 "peaks"

edit - one thing to add to this... these still are a replacement forged piston... piston crowns typically need a bit of burnishing/sanding(or steel wool-ing) to knock the edges back anyway, in this case I'll show how.

The new pistons arrive....




Using a diamond abrasive band I remove the 4 offending protrusions, and then using a 220 buff, I work the entire crown




A different perspective....



the arrows are pointing to where the 4 offenders were removed.... the "back" 2 arrows are pointing to the "worst" of the offenders... those by the exhaust valves.


this set of OST/JE pistons is ready for fitment



Pistons:
$675.00 (without crown re-shaping, or any coatings - straight from JE Piston)
Additions:
$40.00 - with OST re-shaped crowns
$75.00 - with slipper coating on the skirts
$75.00 - with ceramic crown coating - NOT available with OST crown work