Both of my Eljer toilets clog with moderate or greater loads. Usually moderate plunging is needed. Any ideas?
Flush more often, known as a Courtesy Flush. As soon as the load starts to gather flush it and any odors away, leaving much less to flush after the loading has completed. Otherwise, you need to replace the toilets with well rated and tested ones.
Start with the toilet's MaP Rating, this is an actual flush performance rating and should be a score of 1000 and nothing less. Then, look at the customer reviews on Home Improvement websites. I've done exceedingly well with the cheapest of toilets that were both 1000 MaP rated and favorably back-up by customer reviews.