I need to work on the cruise afr to start in my 3 circuit holley 80532-1 carbs[1250cfm]x2 I am testing at 14# because idk how low [8#] would effect the afr with flow through the carbs.Currently stepping into the gas slow gets me 13 low rpm to 14.4 at lets say 4500 rpm so I think I need to close some of the emulsion jets li 2 of the 5 [.025 size] I have mufflers,street tires,Insureance but testing is still risky on the street as you may understand .I am working on an electrical issue/reliabillity so I can test at the track t&t.I get on the gas at 1:24 sec into the video.
Nice.....I am building somthing very similar, and I hope mine runs as well as yours. You don't even seem to have the blower lope most do...Very smooth driving....
Mine is also 446 cubes, but with an OEM block and I will be ordering the 8-71 soon from TBS. It was built by a friend of mine that ran it on E85 with an 8-71....How did you come to using two 1250 Dominators? I have a pair of 750's I am going to try. And no boost refrencing?
Nice.....I am building somthing very similar, and I hope mine runs as well as yours. You don't even seem to have the blower lope most do...Very smooth driving....
Mine is also 446 cubes, but with an OEM block and I will be ordering the 8-71 soon from TBS. It was built by a friend of mine that ran it on E85 with an 8-71....How did you come to using two 1250 Dominators? I have a pair of 750's I am going to try. And no boost refrencing?
Boost reference is for blow through applications only. In a draw through there is no pressure on the float bowl. In a blow through the float bowls also see boost, you have to raise the fuel pressure at the 1:1 ratio so the carb works as normal, otherwise the fuel gets forced back into the lines.
68 Barracuda Formula S 340
Re: video of test drive around block
[Re: Dragula]
#3084041 10/07/2212:05 PM10/07/2212:05 PM
Nice.....I am building somthing very similar, and I hope mine runs as well as yours. You don't even seem to have the blower lope most do...Very smooth driving....
Mine is also 446 cubes, but with an OEM block and I will be ordering the 8-71 soon from TBS. It was built by a friend of mine that ran it on E85 with an 8-71....How did you come to using two 1250 Dominators? I have a pair of 750's I am going to try. And no boost refrencing?
Thank you for liking my car! I started with 850's 20yrs ago and my top goal of 20# after I got a Koleno block the cfm requirements went up and blowers don't like restriction so I got as big as I felt I could deal with and on the dyno I lost 100*F from bigger carbs. Setting up the carbs to start and have the least lope takes some time testing what pump shot it takes and how rough it runs getting it warmed up and turns out to be 12.5 afr at idle cold and it warms to about 13.5 and when warmed up the lope starts at 13/1 afr.
I take it you run pump gas? What is target AFR for WOT? And what is your max boost?
No I have run sunoco/VP 110 from the beginning and afr12.or a little lower 11.5 full timing at 34* 9/1 cr 14# for the last 17yrs. with factory iron heads to start and then Edel Victor std pot now,.631 lift 260 dur at .050 112 lsa
I take it you run pump gas? What is target AFR for WOT? And what is your max boost?
No I have run sunoco/VP 110 from the beginning and afr12.or a little lower 11.5 full timing at 34* 9/1 cr 14# for the last 17yrs. with factory iron heads to start and then Edel Victor std pot now,.631 lift 260 dur at .050 112 lsa
Cool....I might bug you later...so much to learn on these boosted setups...Shooting to start at #10 on mine and land around #15 later....Guy I bought it off of, said it has seen #22.....But it was too hairy to drive....
I got a bunch of brass set screws[150 pc] from McMaster Carr for 30$ so I have plenty of jets to adjust the afr and already put in some intermediate jets to startinstead of the air bleeds or emulsion.jsut an fyi.
pretty cool test ride, even if i only got to ride along in the camera.
I enjoy the drive also but my interest was afr most of all then to watch the vac/boost reading and throttle opening for drivability and if you noticed I get boost when the sec's start to open about 1/4 throttle[linkage ratio]. any input on this?
i wish i could offer you some input, but i have zero supercharger experience. however, i would make a "guess" that pulley ratio would have something to do with that. are you running 1:1 or a slight overdrive ratio ? if the AFR was reasonable when the boost came in, i think i would be happy with that. provided it stayed in the proper range with no detonation when floored as well. i'm trying to learn all i can about this, as i would like to use an 8-71 on an early 392 to put in my "eternal project", that 33 dodge humpback delivery. Cab knows way more about this than i probably ever will.
Re: video of test drive around block
[Re: moparx]
#3086005 10/14/2202:18 PM10/14/2202:18 PM
i wish i could offer you some input, but i have zero supercharger experience. however, i would make a "guess" that pulley ratio would have something to do with that. are you running 1:1 or a slight overdrive ratio ? if the AFR was reasonable when the boost came in, i think i would be happy with that. provided it stayed in the proper range with no detonation when floored as well. i'm trying to learn all i can about this, as i would like to use an 8-71 on an early 392 to put in my "eternal project", that 33 dodge humpback delivery. Cab knows way more about this than i probably ever will.
My pulley % is 10% OD 14# I have the afr lean to keep the plugs clean driving to the staging lanes but now I need some fuel to drive it around the neighborhood and be safe under more driving conditions at the track the main[3rd circuit] jets made the afr 11.5 to 1 so I will take from the main what the intermediat jets use.I need to track the rpm drop going from 1 to 2nd part throttle and I think it was 1500 rpm so on a shift it would go from 3500 rpm to 2k with 3.73 gear 28" tire 5k stall 9.5" vert
too bad you aren't closer, i would like to convince you to try a pair of Thermo-Quads. i really like those, and it would be fun to tune those on your combination. i want to try a set on an 8-71 on an early 392. that is the setup i would like to use in my 33 dodge humpback delivery.
Re: video of test drive around block
[Re: moparx]
#3086184 10/15/2210:26 AM10/15/2210:26 AM
too bad you aren't closer, i would like to convince you to try a pair of Thermo-Quads. i really like those, and it would be fun to tune those on your combination. i want to try a set on an 8-71 on an early 392. that is the setup i would like to use in my 33 dodge humpback delivery.
That sounds like a lot of work to fit/test a carb that is small for me[linkage,fuel line...] not even getting into the powervalve side on those carbs to adapt them.I sold a box of about 8 to a PA member a long time ago for under 100$ I believe.
man, i would have jumped on that deal in a heartbeat ! [i'm always too late and a dollar short !]
you are right about how much work it would be to fit up a pair of those carbs. plus, the tuning would certainly be "entertaining" to say the least.............
