Trick Flow 270s show about the same flow at that lift. Those and the rocker arms are likely the next step on the list.
2"+? pipe....4.500 bore will flow somewhat more with a 2"+? pipe.
Oh, now I understand, you were referring to the flow bench so to speak.Well they used a 2" pipe on their head machine when testing the 270, but yes 1.7/8" hdr would be somewhat restrictive for such a large motor. On our RR the hdr (4" collector) is adequate but he only runs a 2.5" exhaust through to the rear cos thats what he had when a 440 and thats how its run@the track, I worked out from our weight/mph is only around 20>25hp loss according to the dyno numbers but he is chasing 10ths NA your not? and you'll have N20 which is going to be interesting with the stick. I reckon you could get away with a 2">2.1/8" step hdr which actually is what we have I think?..not sure, I was told but can't remember.
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the best kind of presentA few days late, but thanks.
I sent the check off for my rotating assembly as my birthday present to me...
I can see an even longer fbbo signiture now