Surface finish

79powerwagon

New member

• Feb 5, 2018

• #1

Can't find much with search...

Looking for a surface finish spec for 12v head.

Took my head to a race shop which typically does 20-30 ra

Too fine?

*i should add, using stock Cummins HG

 

Last edited: Feb 5, 2018

BC847

New member

• Feb 5, 2018

• #2

1.5 ~ 3.2 micrometers (60 ~ 128 microinches).

As per 1993 Factory Service Manual D&W 150-350, Ramcharger, Rear Wheel Drive Truck. Page 9-115.

- Conversion chart:
http://www.mactechonsite.com/wp-content/uploads/Surface-Roughness-Conversion-Chart.pdf

 

Last edited: Feb 5, 2018

79powerwagon

New member

• Feb 5, 2018

• #3

Thank you!

What end of the spectrum is recommended for a performance application?

 

J

jasonc

Active member

• Feb 5, 2018

• #4

Are you gonna oring?

 

79powerwagon

New member

• Feb 5, 2018

• #5

No, just oem gasket and new headbolts

 

79powerwagon

New member

• Feb 5, 2018

• #6

Only a VE pump after all....

Not going too crazy. Not having issues, mainly preventative with 300k+ miles.