408duster

Hello everyone,new here,i just purchased a 73 road runner with a 71 340,and the heads are both stamped with a u and a backward j,the research i dug up said these heads were only in 1970 340 6 pack aar cuda and challenger ta. Does anyone on here know if this is 100% correct?

MercuryDon

The Only info I have is:
2531894 340 1968-1970
3418915 340 1970-1972
Should have 2.02 int. 1.60 exh.
TA heads have offset intake rocker Arms and relocated pushrods to clear a larger intake port.

mr340

The T/A-AAR heads were 915's that have the pushrod bores reamed out for the offset rockers. These were by no means a professional looking job, they look like they were reamed out with a power drill.

Mr.Duster

Can you post some pics of it? They are ta heads if they have a U or O with a J.

mr340

Not necessarily, Those are just casting letters. Look at the pushrod passages, they look like they were just hacked up (because they were) there was no special casting for 6 pak heads they used the the big valve 340 heads and just modified them.

408duster

thanks for the repleys everyone, if there was not a specific casting for ta heads why would there be heads with a u or an o casting? I myself only knew of 340 heads with x or j stamped heads until seeing these.

mr340

I will get a pic of my original 340 heads and all the casting marks also.

MercuryDon

The book I have says the intake ports were larger than a normal 340 as well but does not give the specs.