Fixing a Modified 2004 Cobra 4V intake

[TJS]

This intake manifold was modified by someone and used to thin of material after modding the intake to make it a short runner.
Here is the problem,too thin of plate and it acts like a drum and under boost it balloons out and cracks the welds.



Intake set up on the JIG plate on the mill. I had to get pretty creative with the hold downs to clamp it to the JIG plate. I might drill and tap the JIG plate for the next intake for the clamp studs. I did not clamp it really tight as not to warp the manifold.



This is after a couple of passes with the cutter. I only took off about .015" at a time.



Just another pic.

[TJS]

This is after about the 5th or 6th pass, I lost count. You can see the trumpets epoxied on there. I still have to machine some more material off as to get all the weld off. Time for dinner, tomorrow is another day.




Man I have a lot of cleaning to do. Nice expoy huh.




I am going to make a pattern out of construction paper but I need to cut it out in such a way that edge of the new plate does not match the edge of the intake, the intake material needs to protrude a little more than the plate, this will make for a stronger weld.

T.J.

[TJS]

Finished milling all the welds off and got down to the casting. Also removed the grey coating so it does not contaminate the welds. I will order material on Monday.
T.J.

[TJS]

Ok. Got the plate cut...broke 2 band saw blades doing it.I made the bridges for the side plates. The one in the pic is rosette (plug) welded as well for more strength. I have the other side plate bridge made up but not welded in yet. I will be finishing this project up tomorrow. The main cover plate is almost 3/16" thick 6061. It ain't going anywhere.
T.J.

[TJS]

Finished it up. Used 185 amps, 76 Balance and 125 Hz for the frequency.





The customer was happy and is going to put 25psi of boost through it, let's hope it holds.
T.J.

[Tryagn5]

Orginal welds looked pretty shabby, probably would have been saved by rewelding and installing ribs on the bottom, not sure if there was space. However Nice job, with 25lbs of boost that motor should be in the 800-900hp range!
Kevin

[TJS]

Orginal welds looked pretty shabby, probably would have been saved by rewelding and installing ribs on the bottom, not sure if there was space. However Nice job, with 25lbs of boost that motor should be in the 800-900hp range!
Kevin

The plate was too thin to save, plus it was powder coated, which would have taken even more time to get it clean for welding. A new plate was the only way to go.
T.J.

[Stillwelding]

Finished it up. Used 185 amps, 76 Balance and 125 Hz for the frequency.





The customer was happy and is going to put 25psi of boost through it, let's hope it holds.
T.J.

Nice work "Lefty".

[ligito]

Just out of curiosity, never having used either tool.
Would a suface grinder remove the plate and a plasma cutter rather than a band saw cut out the new one?

[TJS]

Just out of curiosity, never having used either tool.
Would a suface grinder remove the plate and a plasma cutter rather than a band saw cut out the new one?

Possibly for the surface grinder but I think wheel material would get imbedded in the aluminum which would be a bad thing. As for plasma cutting aluminum, it leaves a wierd cut on the kerf area. I still would have to grind it with a carbide cutter. CNCing a plate with a cutter would be the best.
T.J.