Help I D small block heads.

[RAT ROD AL]

I have a pair of small block heads that I got a few years back. Had run them through the machine shop, Had 2.02 valves installed, guides ect. Just wondering how good of a head they are for just a street car. I see 360 cast in the runners under the valve covers along with ( best I can make out) is 3418915 on both . Any help would be appreciated, Thanks AL

 

[Mtrhead]

It's a J head very desirable 340/360 head

 

[Alaskan_TA]

Ignore the letter.

915 heads can have J, O, U or Z letters but they are all 915 castings.

On 340s, 2.02 intakes, smaller on 360s.

Some were also used on the AARs & T/As with offset intake push rod holes.

 

[RAT ROD AL]

I've seen X and J cast in other heads by the spark plug hole ,but don't see any on these. Thanks for the info guys

 

[Locomotion]

I've seen X and J cast in other heads by the spark plug hole ,but don't see any on these. Thanks for the info guys

X heads were only 894 heads. The 915 heads were the original 360 heads, but also used on 340's starting in 1970, but machined according to application/year.

Only bad thing about 2.02" heads is that you don't know how many valve jobs they've already had. That sinks the valve & seats and reduces flow. Taking the same 915 head with 1.88" intakes and machining them for 2.02" will provide a nice, fresh, high seat and can be made more consistent through them all.