Do block huggers effect hp

mderoy340 said
Here's the Magnum on a different engine and test.
http://www.hotrod.com/how-to/engine/1406-comparing-headers-and-manifolds/

Don't get me wrong, I think you offer a good alternative for those that choose to run manifolds. I swapped out my 73 340 manifolds (which are the worst flowing of the 340 manifolds) and dropped in the Summit 1 5/8 headers everyone knocks and got a good bang for the buck hp wise.

The 360 manifolds shown in the web site may or may not be the "large hole" 360 manifolds that I'm taking about. There are two different 360 manifolds that look exactly like the ones in that test. Without seeing the manifold casting number there's no way I can tell if it's the large hole 360 magnum because Mopar used the exact same shape manifold for both the large hole (2 1/8") and the smaller hole (1 7/8"). Besides measuring the exit hole, there's virtually no way to tell the difference unless you look at the casting number on the manifold itself. I can't see (make out) the casting number at the web site you posted.
Just like the other web site posted earlier, it say's they used a 360 manifold but the one shown is NOT a large hole manifold. I have one of those right now and I know the exit hole is small. I know you're not poking at me...LOL!! It just makes me angry when these Hot Rod articles don't tell you the casting number on the manifolds they test. I mean if they told you the casting numbers everyone would know what to do, or what not to do, RIGHT?? But without the casting number the test is worthless because I have bought many, many, many of the so called "magnum" manifolds. Some have a large hole and some don't. They look the same on the outside (casting shape) but believe me....there are BIG differences. The magnum manifold was produced from 1991 to somewhere in the late 90s, very few of them had a large exit hole. The driver's side and the passenger side "magnum" manifolds both have a twin that does not have the large hole. There are many, many more of the EVIL (small hole) twins than there are large hole.
I can go to ebay right now and see two magnum manifolds that look exactly alike but one will have a small hole and the other will have a large hole.

Fellow Mopar enthusiast!!!
Treblig