Does this quote out of my American Engine Data Book make sense?
"The intake ports for the MR measured 1.34 x 2.34 in. wihile the HR's ports were 1.34x2.72. Actually, the MR's port dimensions weren't anything really new, being the same as on the 1960-1962 HP 352 and 390 cid engines. The same heads were later used on the 1968 - 1970 428 CJ eninges but with smaller valves. The difference between these heads and all the others is that the MR heads used much larger valves, 2.195 in. intake and 1.73 in. exhaust."
So, it appears they are planning the use of a medium riser reproduction dual quad intake on my street Cobra engine with 390 HP heads - and I have a feeling it may not fit under the hood.
