That's hard to believe but very good to know. Did you happen to reach out to a QF tech just to hear their response. That definately could ruin a guy's day with such a basic build. Wonder what an out of the box (smaller) 950 hp holley would have done. Shops/individuals on this side of the state use them a lot with very little tunning in the 500-650 hp range. Amazing how far off that 850 QF was. WOW.... I understand you didn't spec anything and got what you were handed but who woulda ever thought.

Btw Thanks for the thread. Always good info and helpful to others.

x2 !!

Possibly with 100 less hp this would have been ok, i continue to be amazed when norm.mods something a slight bit how.much it changes. He wire gauged the bottom idle feed jets at .037, drilled them to .039, really no difference in size. I cant believe that and making the fuel feed hole size to jets about .020 bigger when they are already .035 bigger than the jets makes jets flow so much more that i went from too lean to rich enough i had to go back down 5 jet numbers AND had afrs i was looking for, Smitty
As far as contacting QF, i never bother doing anything like that anymore if i can just make something work even if it takes a little bit. I do have a friend who couldn.t make a different QF carb work the way he wanted on a sbc powered hotrod car (a BRAWLER, marketing hype) and went around and round with them on the phone. I had a different qf 1050 here i use as my "dyno" carb to.make peoples stuff work right when they have problems (its had various mods), he stuck that on temporarily and his idle/drivability problems went away BUT he could have simply paid norm to straighten it out. I never heard outcome of what he did, he only tested with.my then i got it back, he was getting a different carb or sent it back to them I think.

Interesting. I run quick fuel 850s on warmed up 502s and had none of these problems. I have my jet sizes written down at home but I’m 78-80 primary and 85ish secondary. 12.5 cruise. I don’t have the rest of the numbers off the top of my head. Have her a little extra on the secondaries for 7/8 cylinders since of course I’m reading all 4 cylinders on each side in the boat.

How warmed up, cylinder heads?, Cam? Intake etc, thanks

You've got a good guy there "Norm". To bad but before to long not many of the carb wizards will be around as technology is changing so rapidly. First thing I probably would've thought of was the needle and seat size but that was ruled out in your first thread from everything you mentioned. I've talked to Norm on the phone a couple of times. Full of knowledge without a doubt and very pleasant to boot. Fortunately for your customer he was on site. Likely saved him some $$$ in the long run.

Cant blame your for not calling a tech. They are hit and miss these days also.

EQ heads. Kept compression low for blowers (which I haven’t added yet). 8.7:1. Comp cams. .243/.251 .627/.632. Merlin x intakes. 2 1 inch spacers. Daytona ignitions. Dyno tuning was done in full marine trim. They were quite rich when in the boat. Had to lean them out some

“marine” carbs
 

OP - I like that you put “Marine” in quotes. I bought two new QuickFuel “marine” carbs. 1 season and all the linkage was rusty.

We debated needle and seat change, that was Norms first comment BUT IMO we were using less than 300 lbs per hr fuel, barely over 250 and I was seeing lean part throttle also so felt it was overal calibration, Smitty