I've got about 80 passes and a few races on my 1320 since buying it late in 2021. All of the following comments are "YMMV"...
- Mine has the full upgraded interior and I weigh 200+; I don't recall exactly what it scaled last year, but definitely over 4300
- I'd say mine is basically a 12.0 car that has dipped into the 11.8s under really good conditions... or slowed down into the 12.2s-12.3s when the atmospheric conditions swing to the hot & humid side
- I see where some people post how their "stock" 1320s are busting mid-11s, but also know of folks who have never seen an ET slip faster than 12.x with theirs
- My original expectation was that it would be really consistent since it's "all electronics"... but it will do stuff like mysteriously slow down a tenth & 1 MPH for no apparent reason between passes
- I'd say the grains of water in the air is a big -- possibly the biggest -- predictor or performance with my car, even more so than the basic DA measurements; I've watched the DA fall significantly without any performance improvement because the humidity & water grains went up as the DA fell
- Heat soak hurts the car's consistency, too; I only started putting ice bags on the intake between passes the last time I raced in 2022, although I'm not even sure it helped
- Can't say if it's the car or the driver or both, but some days I've put together a string of decent .0x lights, and other events I swear I'm doing the same thing and can't get under .1x. FWIW, I don't deep stage. On a .500 pro tree, the best RTs I could get were in the .26-.30 range
- Factory-size 275/40R20 drag radials are totally hit and miss; they'll dead-hook or they'll spin & hop cuz the short sidewalls are unforgiving of less-than-ideal track prep; I made the decision to stop using the 20" setup at the track because it's simply too unpredictable
- You'll see it's pretty common for Scat Packs in general, and 1320s in particular, to be using either 18" or 17" rear wheel setups to get a bigger selection of tires with taller sidewalls for more consistent launches; I have alternate wheels with either 305/40R18 or 305/45R18 drag radials to use, instead
- Only a very small percentage of 1320 owners use the trans brake feature cuz the cars seem just as quick off the foot brake and the trans brake procedure is awkward to follow; I never bothered testing it after the general consensus is it's more of a gimmick than a benefit

I still love the car, but IMO it's not an effective bracket racer as delivered. I haven't gone back to the track since the last event I ran in fall 2022. Figured if I wanted to be serious about going rounds that I need to pull my head outta my a$$ and get the '73 back on the road & track, since it's still a legit street/strip car that gets driven to the track.