same concerns. just replaced 530 dr2 no o ring race chain with 530 drz2 no o ring chain both 150 link. 500 lb diff. in strength. well known race shop also told me weight diff. would be slight, go with stronger chain, not true, 1 lb. heavier from 8 to 9 lb chain alone. this is a lot of chain weight for a 1k, about twice the weight of original stk. length chain. believe this chain is overkill on 07 nitrous ten as rider is smooth and launches at 6k. regret not sending it back. curious what your chain weighs? weigh it against your old one for perspective. can't answer your et question, but more reciprocating weight absorbs more power, what racer wants to lose any et unecessarily. consider power output and launch style in your decision.
Last edited by gazx10; 03-29-2013 at 10:47 PM.