Magnus Motorsports

[Matt D.]

What is this, SBR 2.0?

[sleepydsm]

That guy Greg, who did the intake flow testing, said he had a nice SMIM design and made, but was just looking for a local company to sell them...

Looks very nice.

[blageo23]

Just got off the phone with Sean at Magnus, great guy to deal with. Very helpful and took full responsibility for the product they sent. everything is being worked out.
This thread was never meant to totally flame Magnus. They are a great company and make a great product. I understand that the amount they produce there are going to be mistakes. And maybe if I wasn't such a hard customer and have one off parts made it would have been better.
Anyways They are dealing with the problem and I am once again a satisfied customer!

[Kracka]

Until next time...again?

[iceminion]

The magnus that I bought was fine, i believe some of them crack by the #4 tube because of its proximity to the TB and the intercooling pipes.

Most people don't think about the stresses that the intake manifold experiences from the engine shaking and especially how bad it is if the intercooling piping is setup so there isnt room to flex.

Just look at the stock manifold, it has a steel brackets, one on the top and one on the bottom...I have always removed both with no ill effects, but still, mitsubisihi engineers knew that the intake manifold was one of those parts that needed to be over-designed.

[1ViciousGSX]

As Jakey noted earlier in this thread, I had my problems with Magnus, and I gave them a fair thread about it, as some of the issues were not all their fault, although most were. But what did go wrong on Magnus's end never should have happened.

Not that I'm trying to defend Magnus on this, but there are two different issues in this thread.

1. The out of the box problems are very disappointing, especially for the money these intakes cost. Never should happen that way and just a visual inspection before boxing it up would/should have caught it. I don't think they pressure test each one and I can't think of anybody else that does either. But that doesn't mean others don't, I just don't know of them. Either way, Magnus dropped the ball on this one.

2. On a SMIM, there is a constant flexing of the metal that over time can crack a weld. Boost somewhat "balloons" them up a little and vacuum pulls them inward. This is a problem when using flat sheeting in this type of application. If the plenum were a completely round tube, the stresses would be distributed evenly. Welds are by nature meant to handle straight pulling forces, but when flat sheets are welded at 45 deg, 90 deg or 120 deg angles, and those flat sheets flex due to boost/vacuum, this causing flexing at the weld, which over time will fail. So over time a weld will crack and/or blow under boost. It's just the nature of using sheet metal. The bigger the areas of the sheet metal, the more flexing there is. That's why they seem to crack closer to the #3 & #4 runner. If you want to avoid it completely, go with a cast piece. Downside to a cast piece is extra weight.

[Kracka]

I know cast intercooler end-tanks weigh less than their welded sheet metal counterparts. Not so with intake manifolds?

[tpunx99GSX]

I know cast intercooler end-tanks weigh less than their welded sheet metal counterparts. Not so with intake manifolds?

the magnus intake mani is REALLY light. Im almost wondering why they dont use a thicker metal, probably eliminate a lot of the cracking issues because they would use a thicker weld as well. The walls of the SMIM are pretty thin.

[1ViciousGSX]

I know cast intercooler end-tanks weigh less than their welded sheet metal counterparts. Not so with intake manifolds?
I've never seen a cast manifold that was lighter than a SMIM, is there one out there?

[tpunx99GSX]

someone should make a Carbon Fiber intake manifold, that would be tight.

edit: The honda guys have them looks like a really sweet peice. http://www.advancedinductionresearch.com/