HKS Exhaust Install Issues

sandersd

Just installed an HKS Hi-Power exhaust on my 2014 Nismo. It fits perfectly and was a snap to bolt up but I do have one leak I can't seal properly by tightening the bolts.

The older model had an all welded h-pipe crossover:
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The newer models have a bolted flange:
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Unfortunately there is no way to put a socket on the nut or bolt head to tighten it. I can barely get an open end wrench on by angling it 45 degrees on the bolt head and using a box-end on the nut side. I even added another washer to move the head away from the rolled flange but it's still difficult.
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I tried unbolting the flanges after the crossover to allow the pipes to be drawn together more easily but no luck - it still leaks. Furthermore, the flange bolts are torqued to 50 ft lbs and water still drips from them although I can't hear or feel any air leakage.
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I can only get it so tight with the open end wrenches and the crossover still leaks in the center between the bolts. I think my only option is to remove the entire exhaust and reassemble it using high temp RTV.

Anyone else had to deal with this issue and how did you resolve it?

On a positive note I didn't have to remove the shield to clear the muffler. The shield on my Nismo is thin sheet metal, not plastic, and I simply bent it slightly to provide clearance.
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The hanger for the driver side muffler (the one in front) needed to be modified. It has an extension that lowers the muffler hanger but that has to be removed. The bolt that attaches the rubber must be either replaced with a shorter bolt, trimmed shorter to clear, or a spacer used to prevent it from hitting the horizontal damper mounting bracket.
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After I get the leak corrected I'll add a stack of washers as a spacer to properly tighten the bolt.

Any suggestions are appreciated.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood