Dyno'd the Magnum.
Guys, here the facts. I'm running a 408 based on a Magnum 5.9 block with Eddy Alu. heads. I wanted my engine to "breath" as best I could afford. When shopping for a intake it seemed that an Air Gap was the way to go for my application so I started shopping around for price and quality. I decided to go with the off Shore Copy from e-Bay because it was half the price. Now you asking yourself why would he do that after spending big $'s on Eddy Alu. Heads? Duh!
I bough the heads a few month earlier. The one Eddy advertises as "BOLT ON". I work in helicopter maintenance QA and "Bolt On" is a warning sign. I took my new in the box, "BOLT ON"" heads to a very high end race shop to have them inspected. I'm glad I did. If I had of BOLTED ON these heads there would of been a failure. They were full of swarf (machine particles/not clean) several of the valve guides were not within any specs. I was really upset and ask the machine shop for a break down report to go back to Eddy. The laughed and said I wasnt the only one and I wasn't going to get any place with the distributor or the manufacturer. They and customers had tried. BTW, I saw all the is first hand in the shop. Another $350.00 the sp called "BOLT ON" heads were as manufacture advertised acceptable.
Please stay with me. I'm getting the intake.
As I researched this more so I could sleep at night and BTW my wife is from China and a 2 PHD. Engineer. So I have some insight to "Off Shore" products. Eddy heads are not manufactured in the good old USA. They are assembled in the USA. There is a big difference boys. There is where the quality goes out the window. Asia is not know for it's quality control. Where ever Eddy has it's parts fabricated is poor, the final assembly mabe in USA. Giving the impression that we are supporting North American (USA/CANADIAN) industry. NOT!
I decided to test my theory. I bought a knock off air gap intake manifold from e-bay. When it arrived I took it to one of largest performance parts suppliers in this area where I have a buddy in sales who I spend a lot of money with. We put the Eddy next to the China intake. Well other than the outside finish and a few none technical differences I would even go as far as the say the casting mold have a few things in common. This does not surprise me. Look at other products like Yamaha, Honda. The OEM is always looking for profit. Its just business and if they can have it fabricated or parts thereof off shore for a 10th of the cost it make good business sense. But quality suffers. I suspect, as with other products USA manufacturers contract off shore companies to make things for them but, what happens is someone over there decides to make a knock off of the same or very close design. In aviation these are called break out parts. Bell Helicopters has a full time division fighting these parts because they do not received the same quality control. On the bench they look the same. Ive see many aircraft parts like this. Its my job to seek them out. Another story.
I took the off shore air gap to the machine shop for inspection. Guess what. It was no different in defects as the other hi end intake manifolds or Eddy Air Gaps the shop has seen in the past. Including stock cast manifolds. Go figure. Bolt on means BS. I cant stress enough to make sure you are getting what you pay for and read & understand the small print. My off shore air gap knock intake manifold is off is working just fine at about $200.00 less than an Eddy.