trans am heads

[tilsberry]

Hi
I am restoring a 78 TA and I would like some definitive info regarding the heads on my motor (400) They are both 12 code (cast into the upper side of the centre ports and the date codes are - H089 (pass side) and J179 (drivers side) I have looked on the www and the info is a bit conflicting. HELP!!!!!?????

 

[melsg5]

I can understand your confustion but the answer is based on the date codes, which are 08/08/1969 and 10/17/1969, and the 12 head code, somebody installed heads from a 1970 Ram Air III. The dates are too late in 1969 to have been used in 1969. They are high compession heads which on the original application had about 10.5:1 ratio. Depending upon what the point is of your restoration I would most definitely keep them because they are worth at least 40HP compared to the original 1978 heads. You can refer to this site for the information.

http://www.pontiacpower.net/headcast.html

 

[tilsberry]

Thanks for clearing that up. I will definitely keep them on the engine. I have fitted an Edelbrock performance cam and the engine already was fitted with an edelbrock inlet maifold and holley 750. Although its got stock exhaust manifolds I think the engine should perform quite well. The car was originally owned by a guy who was quite a big name in the 70's and 80's English drag racing scene so i guess he had originally fitted them as he would have had access to all sorts of go faster goodies! Thanks again for your help