Off the shelf (not FM) 83.5mm 8.6:1 wisecos. About to send pistons and block off for machining.

Goal is 325-350whp. Im thinking. 0035-.004 will be good for my application. But want to see what others are doing

Whats your piston to wall ? And does it slap ?

 

I honestly can't remember mine but it was whatever wiseco recommended which I believe to be .0035. I get very very minor slap on very cold mornings and practically none when it's 60* or warmer outside. I have run this clearance for 6 years now with this particular engine and I don't consume a bunch of oil and the engine makes good power and has been happy.

 

I’m just building my engine around wiseco pistons. Can anyone confirm that pistons to wall dimension needs to allow for total 0.001 skirt coating thickness? (0.0005 per side)

So for a target of 0.0035 piston to wall clearance you measure piston od and subtract 0.001 then aim for a cylinder diameter that is greater by 0.0035?

Or simply a cylinder wall diameter that is 0.0025 greater than measured piston diameter?

 

I used OTS non-coated pistons on my current build. .0037-.0039" average clearance. I would contact Wiseco about the change in clearance with the addition of skirt coating.