The TBI will not supply enough fuel for the magnum engine, it will run very lean as you push the accelerator. There is not enough flexibility in the programing to do that safely. If you insist on doing it wrong than at least get a 5.9 computer and throttle body from a full size truck, it will be closer to correct but still not right.
The knock off manifold is just as much a "hack job" as modifying and bolting on an LA intake, they are junk. The one I had would rock around in between the heads on a squaredecked block, it needed squared up it self, it was cheaper to buy the eddy and bolt it on than it was to buy and correct the knock off.
I have put LA performer intakes on magnum motors and the port was alighned decently as it was a smaller port dumping into a bigger port and with a thermoquad it ran awesome. It is also very easy to open up the ports a hair for even better alighnment.
Just curious what facts you rely on to say that the TBI setup cannot supply enough fuel for the magnum engine. Have you tried this or are you just speculating?
I don't know, I see people posting up totally ridiculous things like putting 750cfm double pumper carbs on 318 engines and say how much power they are making so....
I suppose it could run lean somewhere, I guess I'll real time the fuel trims and see if the computer is trying to compensate. I'm used to dealing with mass air and speed density setups from much newer vehicles so I'll have to look into how this TBI setup works. Maybe I can add some fuel pressure or something with a piggyback, I think I have an emanage laying around somewhere.
I do have a 650cfm 4 barrel carb I could put on there if the TBI does not work but to me that is still too big of a carb for a 318cid engine. I really hate to put a carb on there, I'm not building a race car, it's just a low rider with a V8 for a go getter for my business.
I put the "hack" intake on, and it fit perfectly so I don't know, maybe you got a [censored] casting or maybe your machine shop did what they always do and say "its not them, its you" because I have yet to meet a machinist that has ever jacked up an engine.
