I have fought this fight. Wanted a tight street converter for my 540 Hemi so that the tranny didn't feel like a slush box on the street. Started with PTC which has been my go-to converter builder for the last few converters and have always been happy with them. Until this last go around wanting a tight converter for a very torquey street engine. They tried twice. Flash was mid to upper 4k. Driving around was not crisp at all, just was way too spongy.

Called Lenny at UCC. First, he told me that the 9" was really too small for what I wanted, but that the 11" stuff was getting difficult to find and very expensive. I told him that I had some motor home converters laying around but he said that there were no parts for them, so...........

I sent the converter to him, he made a few adjustments and made a few suggestions on my end such as a fluid change. And it is much better now. Flash is about 4k and it is much crisper around town. Frankly, I would like it to be a bit snappier down low, but it is not bad like it is. My car likes to idle about 950 and he helped that, too.

And one last thing, check the snout on what ever converter you get. The last two that I have gotten have been a little bit too big to seat in the crank and I had to dress them down a bit. I only figured that out a few years ago after fighting converter bolts that wouldn't stay tight.