o in place of the x or j

[moparman_76]

i have a set of heads for a small block and where the x or the j would be there is an o. does anyone know what these heads were used on any help would be appreciated thanks

 

[Jack Meoff]

Hopefully an expert will chime in....

 

[76volareman]

Are they a 894 or 915 casting number? 1.88 or 2.02 intake valve? Usually O heads were the lastnof the 340's. 72-73. But i think some were on the same year 360's too but with 1.88" intake valves.

 

[moparman_76]

the heads have had work done to them there 202 intakes and 188 exhaust and have been ported an polished not sure of the casting number would have to check next i go to my storage unit.

 

[crackedback]

There are engines that have had an X and J or any variation of those letters straight form the factory over the years.

I prefer to use the 894 X heads with another X. Any of the 915s with letters X O U J N will work together as long as valve sizing is the same. Not a lot of difference between any of those early LA 340 heads.

An O head should be a 915 casting. That head would have been used on 1970-1972 340 and 360 engines.

The 915 casting was also used as the head for 340 T/A engines which adds to the fun with uninformed sellers, moved pushrod holes.

 

[moparman_76]

There are engines that have had an X and J or any variation of those letters straight form the factory over the years.

I prefer to use the 894 X heads with another X. Any of the 915s with letters X O U J N will work together as long as valve sizing is the same. Not a lot of difference between any of those early LA 340 heads.

An O head should be a 915 casting. That head would have been used on 1970-1972 340 and 360 engines.

The 915 casting was also used as the head for 340 T/A engines which adds to the fun with uninformed sellers, moved pushrod holes.

so if there a 340 T/A heads does that mean they can only be used on a ta block cause of the moved push rod holes?

 

[crackedback]

No they can be used on any la block.

Doubtful you have a pair as they are not common. Pushrod holes are at a fairly hard angle through the castings