understanding ilmor differences/generations

[Lars]

Looking for a used boat and came up with some questions on the newer engines ... .

early ilmor engines appear to be all red with MV8 on top, where as later ones are all blue with 5000 on the top. Are these the exact same engine? If they are, when did they switch from Red to blue?

Also, with regard to the 6.2L, when did that become direct injected? pros/cons for MPI verses the direct injection?

[jpwhit]

They changed the color of the 5.7L from Red to Blue when they changed all the engine names with the introduction of the GDI engines in 2016. Since the engine displacement no longer corresponds with power, they renamed the 5.7L to the 5000 MPI and the GDI 5.3L became the 5500 GDI. I'm pretty sure the new engine became available in the 2017 MasterCraft model year. I think that's when MasterCraft switched from the 6.2L MPI to the 6.2L GDI, but I'm not positive because ilmor still makes both engines. There may have been some overlap where you could get either 6.2L engine.

I'm not aware of any significant differences between the red 5.7L MPI and the Blue 5000 MPI.

In terms of the MPI vs GDI, like everything there are Pro's and Con's. The GDI engines are more efficient and therefore generate more power for the same displacement and get better fuel economy. But like any new technology, there have been some growing pains. The GDI engine, at least until very recently, had a new raw water pump with a 90 degree gear drive such that the impeller faced outwards and was very easy to change. But, the 90 degree gear drives haven't been holding up.

A more general issue with Direct Injection engines is that fuel doesn't pass over the intake valves like it does in an MPI engine. So, a lot of Direct Injection engine have required walnut blasting of the intake valves to remove carbon build up. In MPI engines the fuel passing over the intake valves keep carbon deposits from building up. Most cars with Direct Injection have needed to be cleaned about every 50k miles. We're probably just getting to the timeframe where we'll see if that also hold true with GDI engine in boats. You have to remove the intake manifold, and have a walnut blaster to perform the cleaning.

Since all your pictures are of ProStar's I'm assuming you are looking for one of those. IMO, the 5.7L is more than adequate unless you're at high altitude, a jumper, or you have an extremely short setup for the slalom course. I have the 5000 MPI in my 2019 ProStar and have no regrets. And for reference, I have the 6.2L MPI in my 2014 X25 so I'm familiar with the higher power as well. One of the slalom courses I ski only has about 1800ft of lake, so it's not a long setup at all, and the 5000 MPI gets me up to 34.2 by the time the boat hits the pre-gates.

[Lars]

Thanks for the detailed response! helps a lot. You are right, looking at prostars. Don't think I've see any with the 5.3, all of them are either the 5.7, 6.2, or 6.0 after 2019

[jpwhit]

I know you likely don't want to wait, but really the best time to buy a ProStar is in the fall. What I've done a couple of times now with buying competition ski boats, is to negotiate the deal and sign a simple agreement with someone that plans to upgrade to a new boat after the season ends. Which means I usually get the boat in the October timeframe. These types of sellers typically are willing to offer a very fair price in exchange for the peace of mind that they have the boat sold before taking delivery of their new boat. I've purchased a 2011 Nautique 200 and a 2019 ProStar through this type of arrangement. In both cases the boats were one season old when I got them with about a 100 hours of use. We also do the same thing for our club boat in the Ski Club I belong too.

[BROUSSARD]

Lars The 5.3 was never offered in the ProStar.

The 5.7 L was the standard engine for the ProStar from 2014-2019. The transmission was changed from a 1:22:1 to a 1.26:1 for 2015-2019.
The base engine changed to a 6.0 L for the 2020 model year.

A 6.2 L was offered as an optional upgrade for the 2014-2020 ProStar. The 6.2 MPI was used from 2014-2016 while the 6.2 GDI was used from 2017-2020.

[Lars]

Great info!

I don't mind waiting, but due to the reduced/delayed production of the 2022 prostars, its harder to find people that are planning on upgrading. I've emailed a few ski schools who will have something for sale at some point, but when that is and what the price will be is still not known by them. I was offered a nice 2021 with under 300 hours but that's more than we're looking to spend.