[Anthony]

The single four dual plane intake for Hi-riser heads (C4AEsomething) is only 1/2" higher than the single four dual plane for med riser heads. I know, I measured them. The dual four intake for high riser heads I believe is alot taller, and required the bubble on T-bolt cars. I don't have one to measure.

Although it is written that the comp cars came standard with Hi-riser heads, I think most came with med riser. I think all, definitely most, of the S/C's came with med risers. I had asked this question to somebody who has owned an original for a long time, somebody who I thought was very knowledgeable on these cars, and he said he knew of one car that he thought came originally with HR heads. There may be more.