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2 circuit versus 3 circuit Dominators #1511608 10/02/13 07:58 PM 10/02/13 07:58 PM
Joined: Jan 2003 Posts: 4,275 Morrow, OH markz528 OP master
markz528 OP master Joined: Jan 2003 Posts: 4,275 Morrow, OH	How much of an advantage do 3 circuit Dominators have over 2 circuit Dominators is a drag car? The car in question is my Coronet that makes around 800 hp and runs 9.60's. 67 Coronet 500 9.610 @ 139.20 mph 67 Coronet 500 (street car) 14.82 @ 94 mph 69 GTX (clone) - build in progress......

Re: 2 circuit versus 3 circuit Dominators [Re: markz528] #1511609 10/02/13 08:17 PM 10/02/13 08:17 PM
Joined: Jan 2003 Posts: 31,050 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 31,050 Oregon	Subject that has been debated over the years. The 3 circuit should be better but they sometimes require a ton of tuning to get the intermediate circuit working correctly in the car. The intermediate circuit is very sensitive to part throttle (super rich at part throttle) so it depends on how you leave the line. If you hold the engine at part throttle against the brake then a three circuit probably won't work for you. Best deal is to call a carb shop and discuss it. I went back to a two circuit 1250 on my 514 engine. The guys at BLP told me the two circuit is adequate up to about 900 hp and then you need the third circuit, but it really depends on the application.

Re: 2 circuit versus 3 circuit Dominators [Re: AndyF] #1511610 10/02/13 08:45 PM 10/02/13 08:45 PM
Joined: Jan 2003 Posts: 4,275 Morrow, OH markz528 OP master
markz528 OP master Joined: Jan 2003 Posts: 4,275 Morrow, OH	That makes a lot of sense. I have a 3 circuit now that I believe is not set up right. My buddy has a 1050 Dominator 2 circuit for sale from a roundy round car (too big for them) at a reasonable price and I was wondering if I should try it. Sounds like it may be a good idea. I'm sure I could borrow it without committing to buy it. Currently I'm leaving on the brake at 3500 rpm with the pedal to the floor. I have been leaving around 4500 rpm in the past. 67 Coronet 500 9.610 @ 139.20 mph 67 Coronet 500 (street car) 14.82 @ 94 mph 69 GTX (clone) - build in progress......

Re: 2 circuit versus 3 circuit Dominators [Re: markz528] #1511611 10/02/13 10:01 PM 10/02/13 10:01 PM
Joined: Jun 2003 Posts: 9,225 Charleston S sixpackgut Drag Week Mod Champion
sixpackgut Drag Week Mod Champion S Joined: Jun 2003 Posts: 9,225 Charleston	I thought the 3 circuit helped cars on the brake with pedal to the floor because air isn't moving fast enough past the boosters Gen 3 power 6.22@110, 9.85@135 Follow @g3hemiswap on instagram performance only racing, CRT, ultimate converter, superior design concepts, ThumperCarbs

Re: 2 circuit versus 3 circuit Dominators [Re: markz528] #1511612 10/02/13 11:21 PM 10/02/13 11:21 PM
Joined: Jan 2003 Posts: 31,050 Oregon A AndyF I Win
AndyF I Win A Joined: Jan 2003 Posts: 31,050 Oregon	If you can borrow the 2 circuit then give it a try. If it is setup up close for your combination it might just work. You can also make some changes to your 3 circuit. It is best to have a wide band to set up a 3 circuit but you can do it old school also. One easy thing to try is to remove the intermediate air bleeds and see how it runs. Holley left the air bleeds out on some 3 circuit carbs. You can also reduce the jet size on the intermediate circuit just to see how it works. Every 3 circuit that I've ever worked on was dead rich in the intermediate circuit and needed to be leaned out a ton.

Re: 2 circuit versus 3 circuit Dominators [Re: AndyF] #1511613 10/03/13 12:18 AM 10/03/13 12:18 AM
Joined: Aug 2003 Posts: 43,228 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,228 Bend,OR USA	Quote: If you can borrow the 2 circuit then give it a try. If it is setup up close for your combination it might just work. You can also make some changes to your 3 circuit. It is best to have a wide band to set up a 3 circuit but you can do it old school also. One easy thing to try is to remove the intermediate air bleeds and see how it runs. Holley left the air bleeds out on some 3 circuit carbs. You can also reduce the jet size on the intermediate circuit just to see how it works. Every 3 circuit that I've ever worked on was dead rich in the intermediate circuit and needed to be leaned out a ton. Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: 2 circuit versus 3 circuit Dominators [Re: AndyF] #1511614 10/03/13 08:20 AM 10/03/13 08:20 AM
Joined: Jan 2003 Posts: 4,275 Morrow, OH markz528 OP master
markz528 OP master Joined: Jan 2003 Posts: 4,275 Morrow, OH	Quote: If you can borrow the 2 circuit then give it a try. If it is setup up close for your combination it might just work. You can also make some changes to your 3 circuit. It is best to have a wide band to set up a 3 circuit but you can do it old school also. One easy thing to try is to remove the intermediate air bleeds and see how it runs. Holley left the air bleeds out on some 3 circuit carbs. You can also reduce the jet size on the intermediate circuit just to see how it works. Every 3 circuit that I've ever worked on was dead rich in the intermediate circuit and needed to be leaned out a ton. That is exactly what I was thinking. In the process of installing the new Racepak data logger so I will have air fuel ratio monitoring next time out. With the 80 intermediate air bleeds in the carb now I think I am WAY rich and that is why the car works so much better on the launch as the weather gets cooler. 67 Coronet 500 9.610 @ 139.20 mph 67 Coronet 500 (street car) 14.82 @ 94 mph 69 GTX (clone) - build in progress......

Re: 2 circuit versus 3 circuit Dominators [Re: markz528] #1511615 10/03/13 09:59 PM 10/03/13 09:59 PM
Joined: Feb 2003 Posts: 1,532 crisfield, maryland 21817 8 82ramIndy493 pro stock
82ramIndy493 pro stock 8 Joined: Feb 2003 Posts: 1,532 crisfield, maryland 21817	Call Jesse at Bigs Performance. He can do the conversion from 3 to 2 cuircuit. He just did mine last year and I am satisfied with it and didn't see any loss of time with it. He can tell you if it will help or hurt you.

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