More aero mods for Toyo? stuck..

[Techdetails1]

Hello all,
2012 Toyo Corolla 1.8 auto, mpg @ 53 hwy. Seems to hit a wall w progress. Any help appreciated. Mods completed: upper & lower-(partial) grill block, pan covers over wheels, engine area belly pan, even tried a pyramid spoiler on trunk-seems to stall mpg @ 50.
Help please!

[freebeard]

What was the 'pyramid spoiler' like?

Many of the things you could do will induce pain; you'd need to decide how much you can take: massive lowering, 3ft boat tail, wheels in skirts and spats.

[Techdetails1]

Pyramid spoiler: pointish @ mid front trunk-to 1/2 car width w 12 degree angle up, overhanging rear edge 4inches,w1/4" gurney. Design was to kick trunk airflow out to sides, sharp edge separation, decreasing drag below trunk Its a DD for a coworker. Also did mirror delete both sides (inside dr. side mirror & convex rear view wider than stk).

[elhigh]

50+ in an auto-equipped Corolla might be as good as it gets. I'm struggling to do that well with a hybrid.

You're beating the EPA highway rating by 50% or more and coming from a bigger engine, more weight, a larger body and a worse transmission for it. You could take the belly pan further aft and consider full skirts on the rear wheels at least, but these are excellent results already.

I've been getting hammered by extensive AC use; I'm thinking the next step is to add ceramic window tint to keep the interior cooler and take some load off the engine that way. That's worth considering.