Hey all....getting back into the Mopar hobby after not having owned a classic one in year. I do have a new Jeep Liberty if that counts...

Anyway, Im looking at buying a 1970 swinger 340. Went and looked at it today. checked the vin number and the fender tag, its an original 340/727 Top Banana car built in Canada, with an original go wing, front discs, and not much else in the way of options. The owner claims it came from the factory with a 904, I didn't want to argue and tell him it didn't but that's another story. Not that important to me anyways, want to build a street/strip car r. I figured the 727 went out years ago, and that's what was in it when he got it. I want to build a street/strip car out of it.

My question concerns the heads. I was reading earlier that some x heads came with a U or an O. One has a U and the other has an o where there would be an X. On the front of the heads, there is an (I) symbol. More like a straight up and down line, but ya know. Motor is all orange, and under a lot of grease.....It runs and drives, hope to drive it next week when the owner gets back in town (wasn't there today)It's mine as far as im concerned either way,......the price is CHEAP by today's standards for an original 340 car. Any info is appreciated fellow Mopar fans.....thanks!

I read on another forum a few minutes ago that one guy said he had seen 1970 model 2.02 heads with a u and an o on them as well......for all intents and purposes x heads without the x cast into them....anybody know for sure though? I can't pull the heads off in his driveway, don't think I can get away with that one.......Like I said, not a huge issue as the price is so cheap and it's def an original 340 car. Im just curious as hell.....

Technically, they aren't "X" heads, but they are equivalent.

There are X, O, U and some J heads that had 2.02 intake valves. Then there a J heads with the 1.94 intake valves, all have the 1.60 exhaust valve. All of these heads are the "915" castings. I happen to have 1 X and 1 O head on my 340, as they are both 2.02s it doesnt bother me.

I just had never seen any without the x cast into them.....or J heads without the J cast into them.....I guess it must be fairly common. thanks for the response......

915 castings have been found with J, O, U & Z - sometimes a combination of two letters on different heads on the same car. The letter itself has no real meaning, all are 915 castings.

X heads were 894 castings.

Depends on the build date of the car. If the car was built between August 1969 and February 1970, I would assume it to have "X" heads. If the car was built after mid February 1970 I would assume it POSSIBLE to have been assembled with a "newer" casting as Chrysler was moving castings toward the 1971 model year.

Brad