If Briggs did indeed mfr the new Toro engine, and it is being branded as Toro opposed to Briggs, my guess is that the quality standard/quality requirement for the mfr of the engine is lower (cheaper components, more defects allowable per X number of engines, etc) than the Briggs quality level, so rather than potentially tarnish the Briggs name with a sub-standard engine, they agreed to make this engine specifically for Toro with the Toro label. In the end, Toro probably decided that the new "Toro" engine is still a significant upgrade over the competition (MTD chinese engines), that it is a small risk for them and a potential huge upside in that they can sell the snowblower for a more competitve price at the big box stores thereby increasing market share. A win- win for everyone except the guy who can't start his Toro in the middle of a blizzard. And to add to that, and maybe this is a bit of a stretch, BUT, realizing that their snowblowers are averaging a lifespan of 16yrs and MTD is 8yrs (arbitrary numbers), they wouldnt mind dropping the lifespan to around 10-12 in order to sell more "replacement" machines to the Toro faithful.
from an earlier message that said they suspected it was a loncin engine, i looked up the loncin engine company (see link below) - and i believe the specs match the 926 engine -- same displacement and the pictures look similar -- i think its a fine engine - i bet toro had to go with a more powerful engine because of complaints on the 826 and brigs couldn't meet the price point/spec without getting too close to the 1028 model-- so they went with this manufacturer -- Toro i am sure is very careful in their sourcing -- especially engines and will not risk the warranty costs and reputation hit for a few bucks -its never been toro's style -- its probably a product positioning thing -- and the next engine up on the brigs was somewhere near the power of the 1028 -- so they couldn't distinguish it by the way under full disclosure- i have a vested interest in the 926oxe -- i just bought one today -- the 826oxe was available but as a prior year model -- only difference was the engine - -- i went with the latest -- again they would not have changed the engine if they didn't think the 826 was underpowered -- these guys are not seeing a tremendous price pressure in the big box stores -- they are holding the price because of their brand -- again i could see if they were going to do something it would be on the lower end by the way - the ariens felt real cheap in comparison http://www.loncinengine.com/Product60/Detailed91/#Text