Last minute check before heads go on...

[euro911sc]

Here we go on deck height again

Engine: Stock 3.0 ROW w/ CIS and 9.8:1
Deck height measured with 2 x 0.25 coppers: 1.04/1.03 mm (top/bot)
Heads were fly cut 0.01" (0.254 mm) with no chamfer

This says to me I need to put in 0.75 of copper to get in the area where I will feel safe running mostly track with some street.

Comments?

Best regards,

Michael

...and the pre-assembly money shot

[Eagledriver]

Sounds to me like you are ok with .5mm of base gasket thickness. The usual deck height is around .030-.040 inches. You are slightly over .040 inches. Just look at the heads where the top of the piston will be going and make sure it looks like the dome "falls away" from the piston at the edge of the cylinder so you are sure the piston won't get closer than .030 inches from the head. I doubt that taking .010 off the heads will cause a problem.

-Andy

[TibetanT]

Subscribing for information purposes.

Good luck with the build, Michael.

[euro911sc]

Andy,

Thanks for the comments. Absolutely right, the actual deck height is good with just a 0.5. I pulled a 0.5 off the engine when I took it apart so that is where I started and I had no spigot machine work. What I was mostly concerned about was piston to valve clearance with my 9.8:1 ROW CIS Pistons. I thought, since I had removed ~0.25mm from the head I should 'replace' it via a base copper to effectively put the parts where they were originally. Still no worries?


Best regards,

Michael

[Eagledriver]

While you should always check the piston to valve clearance when anything has changed, I would expect you will have more than enough clearance as is. The dome on your pistons is the same as my US 9.3 piston (just the flat area is different). I had over 2mm of clearance on all valves with .010 shaved off the heads.

-Andy