How much ET did you loose with the added weight? Many times I've added weight and gone faster. Certainly it's easy to see how you also found some consistency.
I don't recall. I have most of my ET records but don't remember when I added the weight. I slowed the car down to various degrees over the years so it wouldn't be on "kill" and hopefully prolong its life. Also slowed it to run low 11's when I decided to get away from the "box" cars in Super Pro. But I had a milder, unported engine by then. A 3310 750 and 4777 650 were .10 slower than a 4779 on my car. But the 3310 slowed about 1/2 second when the secondaries were kept shut.
The rear suspension was never quite right. But the weight was a band-aid fix under marginal track conditions.