Clifford 4.2l headers?

[Desertjr]

Will these fit on a 4.0 using the 99+ horse shoe intake? I see people stating that are or were running Clifford's "long tube" header. Grandson, nosigma and 1 other. But I haven't found a "long tube" header unless it was 4.2l? From my understanidn these don't fit..

I know our firing order is 1,5,3,6,2,4. So pairing each cylinder 180* would give the best scavenging effects right? Meaning you'd want a header going 1,6,5,2,3,4 right? If a custom built header was made, going 3-2-1 design, You'd want 1,6,5 & 2,3,4 pair together right? Why don't jeep 4.0 header manufactures do this then?


Since I'm currently looking for a header these are things I'm pondering...I'm honestly thinking of going custom. Getting the header primaries as long as possible. Probably 28" or so, longer if possible, but also keep them all equal length, or as close as possible. Priority would go to pairing the groups and getting them as long as possible to keep the torque in the lower rpms. Old 4.2l Clifford's are built with LONG primaries which is what makes me wonder if that's what gradon and the others are saying when they say they run the long tube Clifford's.

[Desertjr]

Also if a custom header isn't an option for me (gonna find out locally first) but if not then getting down into the Doug thorley which everyone claims in the "best" header for the jeep 4.0 has EXTREMELY short primaries which won't support low end at all. Now it does have the tri-y design which helps spreads the torque over a wider area but still..
Then there's the apn which can be had for under 150 to your door. Same tri-y design, primaries are matching 1.5" I believe as the thorley and seem to be longer. "Primaries" meaning first section of tubes. Or is the throley longer because the "secondaries" are longer? I've read ALOT of links on headers already..can anyone shed light here. Ceramic coating isn't an factor here as either would be coated.

Comparison of a banks(apn knock off identical) & a thorley. My thinking says the apn header is better performance wise because the longer primaries...I also understand not much will be gained either way, but I'd rather start out with the better of the 2.