View Single Post
TurboKraft TurboKraft is offline
Registered User
 
TurboKraft's Avatar
 
Join Date: Mar 2005
Location: Phoenix, AZ
Posts: 2,493
Having done this, I'd suggest you don't machine them and instead buy new pistons.

After 9.0:1 CR it gets pretty thin. And thermal coating the crown only helps so much.

It's thickest above the pin bosses, 90deg from the valve reliefs. You can take out a lot of material there. But note how the inside of the piston is pocketed under the valve reliefs -- not a lot of material there to take away, and leaving it leaves a really poor shape for a piston crown. Not combustion-friendly. If you try to machine a really low dome on them, like Turbo 3.6 but 8:1, don't expect them to last long term.

I've got several sets of take-out pistons from client engines built at other tuner shops, plus some of my own early engine experiments. Not pretty. All motors ended up getting replacement pistons or pistons & cylinders.

Just my $0.02 having been there, done that.
__________________
Chris Carroll
TurboKraft, Inc.
Tel. 480.969.0911
email: info@turbokraft.com
http://www.facebook.com/TurboKraft - http://www.instagram.com/TurboKraft
Old 03-25-2010, 11:33 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)