Wow that was an impressive timeslip for 400 hp ! I could try a dual plane too, Fast68Plymouth also recommended that (RPM). I live in somewhat of a rural area so it does see well over 6K regularly though :-)

I probably went through 10 carburetors last year. I actually wound up buying a Barry Grant Gold Claw and gathered up all the venturi sleeves, throttle plates and boosters, so I can go from a 750 to 1050 and alter between down leg and annular boosters. I got a lot of information for that setup from reading Brad’s post here and over on Speed Talk, again a lot of good info. I do agree with the statement that you really can’t go by the ratings (750,850, etc) it is venturi, throttle plate and booster. I will say also that an AFR gauge is a really nice tuning aid. I am probably going to bail off and get a second one for the other side on mine. Between time slips, AFR readings and plugs you can get a pretty good handle on what’s going on but to Dwayne’s point, is there 30 hp hiding probably not. For me I do want to get the most of out what I have to a point, but in reality if you are racing, consistency and maintenance are more important.

I'm generally in agreement here, I think that manifold is hurting your torque without a significant HP payback up top.

A performer RPM will certainly help your upper bottom and probably work the converter harder throughout the middle, I just don't know if I would prefer it over a mildly ported Street Dominator on your 383 which I think will be just as strong through the middle and (at least from my personal experience) a bit better up top.

The Best thing about a BB Mopar is it's so easy to swap the intakes and compare them literally back to back at the track.

Clovis has a good idea regarding the AFR gauge. That is something else I can do over the winter. In a perfect world I will be able to line up an RPM intake and maybe another carb over the winter and try some things out in the spring. Thanks guys!

A vaccuum gauge you can observe going through the traps would help a lot too, I suspect an RPM might be more restrictive up top than a street dominator.

i used a DP4B intake, 850 Thermo-Quad, SSH-25 cam on an otherwise stock 383.
2500 converter and 3.91's in my charger.
that combo worked pretty good for what it was.
best et was 13.56 [i can't remember the mph] but usually ran 13.79-13.90, without getting into the distributor to get a good curve.

Other than it being over 12:1 compression it sounds like a good combo. Being from Michigan maybe I'll see you around? Like some have mentioned, I'd just tweek the carb you have. I'm sure a rear gear would make it feel like you found some power.

I think you're right, I should have went with a little more gear. I am in SW Michigan near Kalamazoo. It looks like you may be on the east side of the state? I have really only met a couple of people from Moparts in person but it sure would be nice to run into more !