I got this sample piston @ end of last week from Wiseco for evaluation.... This will be a new shelf stocking piston for them.

One of their engineers solicited info a while back on what was missing from the piston market for SB Mopar these days & I chimed in that I'd like to see another Dome offering. Every piston company out there had flat tops & Dish pistons but, Ross pretty much had a monopoly on the 4" Crank dome piston market, & their dome is a bit "clunky" & they are only offered in 4.07 bore which really limits you... The Ross piston is pretty basic, they took their 4" flat top & added a large 23 degree Chevy dome profile to it... was'nt alot of thought or effort in it...

The new wiseco has a much nicer SB Mopar specific profiled dome that will fit pretty much any aftermarket SB Chrysler head, B1-BA, Edelbrock, INDY, W2, W5 etc. This should fit any 18 degree SB head. I checked the dome this afternoon in an OOB Edelbrock 63 CC chamber head & clearance was fine.

The Dome displace +8 CC of total volume... For some examples of what this thing will do compression wise:

Typical 408, with 68 CC OOB CNC INDY head: ~13.2:1 compression
416 With 65 CC Edelbrock: 14.0:1

Finally have a decent piece to use off the shelf & can make race gas compression levels with these semi big chamber heads in the 65+ CC range so we don't have to cut the hell out of the deck of heads to build compression with a flat top or order customs to get a good dome piston.

The other 2 big benefits to this new piece to me is the 10 vertical gas ports & the .043"/.043"/3MM ring grooves Finally someone has brought today's technology & put it in an off the shelf piece.

Typical 1.46" CH, .984" pin diameter only (for now, hopefully .927" coming in future) Which will mean 9.583" deck height for zero deck. Should work good with most factory blocks out there unless they've previously been heavily decked in the past.

Skirts are coated, just like their Pro Tru line.

Valve relief depths are around .280" intake & .165" exhaust. The exhaust hopefully is going to get plunged a little deeper in future runs, but depending on head/cam, should be ok as long as the head has'nt been milled to death.

& Lastly, I'm glad they chose to offer them in a wide variety of bore sizes, Diamond is really the only other maker out there who seems to understand not everyone runs 4.03" or 4.07 bores. Finding a good useable 340 & even 360 these days is getting harder & harder, so having piston bore size limit your choices really hurts. These pistons will be avail in 4.03, 4.04, 4.06, 4.08, 4.10 Bore.

I've got a bunch of 4" crank bracket type motors running around out there with flat tops that I wish had these in them. Should be a great piece for future builds.

Kudo's to Wiseco for listening to what the consumers want & making a nice piece.