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| You can see how the stock turbine outlet necks down considerably before merging with the stock downpipe. Most turbo back systems for the Evo X use the stock turbine outlet so this is the cork in the system. The AMS downpipe is big all the way though! |
Looking at the Widemouth you can see it is a truly a big mouth with a large internal volume and smooth bends into the downpipe. At no point does the inlet neck down to less than 3” in diameter. It would be diffcult to fabricate something as free flowing as the AMS casting.
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| A closer look down the pipe throat shows how the radius into the pipe is now very gentile and how there is a huge area for the flows of the wastegate and turbine to converge with the least amount of turbulence. There is no way a fabricated part could conform to this sort of complex shape. At least a fabricated part made at any sort of affordable price! |
The AMS casting is made from high quality 304 stainless with about a 0.125” wall thickness which is great from a corrosion and thermal conductivity standpoint. Stainless steel has about half the thermal conductivity of steel or cast iron so stainless will help control heat in this area. It will also transfer more exhaust heat to the cat to help speed cat light off reducing emissions.
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| To avoid cat damage while tuning and for our later anticipated track use, we got this test pipe from AMS. The pipe fits perfectly and has a provision for an extra 02 sensor bung for tuning as well as the rear secondary OBDII O2 sensor. |
It costs a lot more to tool up an investment casting vs just making a simple tubular fabricated part but AMS doesn’t mess around and they invested more into their parts' tooling to make a better quality, better performing part, one that we think is one of the best for the Evo X on the market.
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| The AMS system is modular and designed to be used with any combination of stock parts and AMS parts. The fit is great! |
The Widemouth downpipe maintains its cast construction to the flex pipe which is a high quality part with a smoothly segmented liner. Many cheaper downpipes use a flex pipe with bellows type inner liners which can cause turbulence reducing flow. After the flex pipe the down pipe continues to use investment cast construction with a thick integral stainless flange connecting the down pipe to the cat.
