6.2 J-code heads same as C-code?

[kapnklug]

One of my cylinder heads is cracked, but I have a junk 6.2 out of an '88 3/4ton suburban. Are the C-code heads the same as the cracked J-code ones?

 

[Tanner]

6.2 C and J code interchange ?? - TheDieselGarage.com

82 Chevy Truck with a 6.5 Military Diesel - TheDieselGarage.com

There are numerous sites on the web dealing with the 6.2 & 6.5 motor...

I recall that J-code heads had different sized valves than the C-code heads. And make sure that the intake mates up to the heads... I'm not near a motor now to check -

'Tanner'

 

[Southern Off Road]

6.2 C and J code interchange ?? - TheDieselGarage.com

82 Chevy Truck with a 6.5 Military Diesel - TheDieselGarage.com

There are numerous sites on the web dealing with the 6.2 & 6.5 motor...

I recall that J-code heads had different sized valves than the C-code heads. And make sure that the intake mates up to the heads... I'm not near a motor now to check -

'Tanner'

i believe u are correct and they make about 30 more hp

 

[ralbelt]

FWIW there is still one 6.2 head for sale in the classifieds. I am committed on two but the seller had 3.

 

[Tanner]

Make sure you change the heads in matched pairs... you do not want to run a C-code on one side
& a J-code on the other...

'Tanner'

 

[Wolf.Dose]

The C code heads are a little different from J code heads, the valve size is different. However, the cam shaft is also different too. The C code engine was the low emmissionen engine for light duty trucks, the J code engine the one for heavy duty emmission. Mechanically, the C code head shoulf fit to a J code engine bock.
Wolf