As of March 2023 IAG Performance announced that effective immediately it would be streamlining its Subaru engine offerings, offering less choices of short blocks but making it easier than ever to choose a block that’s right for your set up. 

Honestly, most people who were browsing the IAG engine offerings thought that there was too much choice when it came to what engine to choose from. And that the “stage” labeling system was a bit confusing and hard to remember. Here is a blog post we created as a comprehensive guide to the IAG engine offering system. 

IAG slimmed down its offerings for a few reasons. 

Reason 1: There were too many offerings,

7 to be exact. There are now 5, still a healthy amount of choice, but not enough to overwhelm the decision-making process. The offerings are more or less the same, two are gone and the rest are just re-named. 

What used to be the Stage 2 is now the IAG 550.

Stage 2 TUFF, is no longer.

Stage 2.5, is now the IAG 750.

Magnum is now the IAG 950.

Stage 4 tuff, is no longer.

Stage 4 extreme, is now the IAG 1150.

As you can see, each name is a number, and that number is the maximum recommended brake horsepower each unit can handle. GENIUS! The old naming system was very confusing to say the least. Now you dream up your desired HP level and pick the befittingly named block. 

Reason 2: Profitability.

Having too many options means having to stock parts for these options, and include systems and production procedures for each option and that gets costly. When sales figures show that you can do with less options, any good company will streamline when possible, and that’s what IAG Performance did. 

Unfortunately, we will miss the stage 2 TUFF, that was our favourite block, but unfortunately it didn’t sell well so IAG axed it. 

We think the online parts-only retailers were to blame for the lack of sales. At Lakeview Automotive, being a Certified IAG Performance installer we understood the Stage 2 tuff, and informed our clients on why to choose it.

While it had a hp rating of only 50 over the stage 2 (from 550 to 600) the informed shopper would have known that it came with an oversized piston and a bored and honed cylinder wall (from 99.5mm in stage 2, to 99.75mm). This allowed IAG better control over piston to wall clearance, and that improved “piston slap” while not a huge deal, a thing all forged motors suffer from. Now, if you want that oversized piston set up you have to jump over to the IAG 750 which is more money and most shoppers probably will stick with the IAG 550, which is still a great unit.