Milled heads

Reply Subscribe

Thread Tools

Search this Thread

Jul 18, 2019 | 12:52 PM

mlm0

Thread Starter

Drifting

Joined: Dec 2012

Posts: 1,504

Likes: 73

From: Georgetown TX

Milled heads

My heads had a 58 cc volume. I had the heads milled flat, but don’t know how much was milled off, so I don’t know what volume they are now. Would it be same to use 57 for calculations, or would they be less then 57. I know without the mill specs, its impossible to know for sure, but I’m just looking for an estimate from someone with experience

Jul 18, 2019 | 03:28 PM

C409

Le Mans Master

Joined: Feb 2005

Posts: 6,478

Likes: 565

From: Clearwater Florida

….. Why are you concerned about a 1 or 2cc difference ? That's likely less than 0.10 change in compression ratio (9.5:1 to 9.6:1) … You could always cc the chambers …..

Last edited by C409; Jul 18, 2019 at 03:30 PM.

Jul 18, 2019 | 04:28 PM

mlm0

Thread Starter

Drifting

Joined: Dec 2012

Posts: 1,504

Likes: 73

From: Georgetown TX

Not so much concerned, as I like to have as much knowledge as I can before I make decisions

Last edited by mlm0; Jul 18, 2019 at 04:29 PM.

Jul 19, 2019 | 11:31 AM

JackDidley

Race Director

Joined: Sep 2003

Posts: 16,836

Likes: 337

From: Database Error Indiana

You could get a lab burette and measure how much liquid it takes to fill the chamber.

Jul 19, 2019 | 01:38 PM

383vett

Race Director

Joined: Apr 2003

Posts: 17,699

Likes: 1,667

From: moraga ca

Normally when heads are milled, only two to three thousands is removed. Nothing to worry about. As Jack mentioned, if concerned, just measure the cc volume.

Jul 20, 2019 | 10:11 PM

cardo0

Le Mans Master

Joined: Oct 2002

Posts: 7,098

Likes: 378

From: Las Vegas - Just stop perpetuating myths please.

If you want an accurate head chamber measurement you need to use liquid. All you need is 5" X 5" sheet of plexiglass with a hole in it and a graduated cylinder. Windshield washer fluid will work to measure the volume. Anything else and your guessing.