"A couple of the key differences between the MPI turbo and Push turbo are that MPI uses an oil pump to circulate the oil and also uses a stainless steel mounting plate (not visible but just under the tunnel) to mount the turbo. MPI is now the approved aftermarket turbo vendor for Yamaha.
Yamaha has changed vendors for the aftermarket turbo it offers for its Nytro MTX mountain sled.
When Yamaha first announced a year ago at Hay Days it was offering a turbo and supercharger as an approved accessory, Push was the official vendor for the turbo while Mountain Performance (MPI) was the official vendor for the supercharger.
However, Yamaha has just announced that MPI is now the approved vendor for both the turbo and supercharger.
Yamaha snowmobile product manager Rob Powers said there are two reasons for the change from Push to MPI turbos.
First, he said. "MPI's response to the customer has been better," and second, "MPI makes a more quality kit."
Powers also stressed that the turbo and supercharger are not factory approved components and are aftermarket products, although MPI is an approved vendor.
There are four significant differences between the Push and MPI turbo.
1. MPI uses a Mitsubishi turbo.
2. MPI uses an oil pump for the return whereas Push relied on vacuum pressure for the oil return. The way it was explained to us is the oil pump is better because on a long pull, say up a mountain, there might not be a vacuum because you're on the throttle. The oil pump will circulate the oil during those long pulls. The vacuum system hasn't been an issue to date but MPI chooses to use the oil pump as a safety precaution to keep oil circulating regardless of vacuum pressure.
3. MPI uses a stainless steel mounting plate rather than a stock muffler bracket as was used on the Push turbo. The gives the turbo a more stable mounting surface.
4. With the MPI turbo, there are three mounting spots for the charge tube as well as an extra mount for the muffler, providing additional support.
"The (MPI) kit is a higher quality kit for the same money," Powers said.
Yamaha strongly recommends sledders purchasing the turbo or supercharger have a dealer install the unit.
We'll give more details on the turbo and supercharger in the November issue of SnoWest, which will focus on four-stroke mountain sleds with and without turbos and superchargers.