JT-03 head- how old is it & is it any better than 109/136/139

[Dirtcarz]

Please - need to know how old this head casting is & is it the same, better, worse
than the JT-109, 136,139 heads out now. I bought a eng with this head on it & was
wondering how old it is . & is there an advantage to update head to JT-109, 136,139
Thanks

 

[optima182]

Not that old of head. I believe dyno cams clone engine comes with this head on it. All the heads you have listed are good castings.