Your forearms will catch up eventually, grip is one area where you have a ton of potential. Finish off every session with more grip work (bar hangs are good as mentioned above).
Also, if you want to keep training past the point where your forearms give out, switch things up a bit to a different variant, horizontal rows after pullups so your hands won't have to support as much weight, or pushups on the floor instead of the ********** system so your hands won't be taxed.

For some reason the forum is blocking out the word s u s p e n s i o n.