Dominators

[Ratacole]

I have older 1050's with the 4 corner idle screws. At WOT do they have any thing to do anythying, or am I on the mains only? Also with out changing jets can I fatten it up by slowing down my blower? Thanks, Mike

[Hotcrusader76]

Are these two or three circuit Dominators? Why not try adjusting the carburetor(s) instead of changing the boost supplied?
~Ty

[Ratacole]

Hotcrusader76:
Are these two or three circuit Dominators?
~Ty How can I tell :confused:

[Hotcrusader76]

Ratacole:
Hotcrusader76:
Are these two or three circuit Dominators?
~Ty How can I tell :confused: Well for starters the three circuit will have six drilled airbleeds on the top of the carburetor mainbody per side, vice only having four per side.
Knowing which version you have can assist many here in tuning your fuel delivery for that lean issue.
Basics- Check you fuel pressure and float level as well, assuming you already did.

[Rexone]

Post the Holley List number from the carb and I'm sure Ty and others here can tell you exactly what you're dealing with.

[Ratacole]

OK, I finally found time to mess with them...
They are two circuit carbs, Holley # 0-9375. Fuel pressure at WOT is 7lbs & float level's are set.

[GofastRacer]

Them dudes are not cheap!.. eek!
9375 (http://www.holley.com/HiOctn/ProdLine/Products/FMS/FMSC/0-9375-1.html)

[Ratacole]

GofastRacer:
Them dudes are not cheap!.. eek!
9375 (http://www.holley.com/HiOctn/ProdLine/Products/FMS/FMSC/0-9375-1.html) Tell me about it.... It would be cheeper to be injected
cry

[GofastRacer]

Now you're talkin, and a lot simpler too!.. :cool: :D :D

[Hotcrusader76]

Either way the 9375 is a three circuit. Great carb to start with. Why do you want to fatten it up? How lean are ya? Give us some more info now that we have your carburetor type.
You can either fatten up the main-jet or down-size your intemediate air-bleed.

[Ratacole]

OK, 12% over 92 jets(all around) 1.29 gears could not get past 6000 rpm. Same set-up but with 1.22 gears, 6000 rpm. I put 98 jets(all around) in and gained 900 rpm. I did a plug reading with the 98's and the plugs look kinda grey or silverish. I just ordered 110's, am I on the right track?
Mike

[Hotcrusader76]

Obviously you're on the right track, but I believe your booster is limiting your fuel. Getting your booster set-up for a blower application such as yours will put ya back in the game with less jetting. IE 12-Hole Annular booster with minimal skirt.
110s wow!
~Ty

[Rexone]

Hotcrusader76:
Obviously you're on the right track, but I believe your booster is limiting your fuel. Getting your booster set-up for a blower application such as yours will put ya back in the game with less jetting. IE 12-Hole Annular booster with minimal skirt.
110s wow!
~Ty You obviously didn't approve that jet size with the democrats before ordering did you?
Ariana is not going to be happy either.
:D

[wideopen545]

i just bought a pair of these and hope they will work for my application 454 with a 871 at 15% over running at 6000 rpm they got to be better than those carters 750s i'am running

[Ratacole]

Hotcrusader76:
Obviously you're on the right track, but I believe your booster is limiting your fuel. Getting your booster set-up for a blower application such as yours will put ya back in the game with less jetting. IE 12-Hole Annular booster with minimal skirt.
110s wow!
~Ty OK, I've done some homework & Holley makes a kit #34-9, Annular Booster Conversion Kit. However it does not say if it is a 12-hole or not. In fact it does not even give me any info on it. In my Holley book it says " The main-system signal generated by these boosters is so strong that main jet size must be reduced by sevral Holley numbers (that would solve my lean condition, yes?). The main disadvantage is, predictably, considerable airflow restriction, due to their large demensions". I have no clue what that ment :confused: . So what will that do to my performance?
MIke
[ October 17, 2003, 08:33 PM: Message edited by: Ratacole ]

[GofastRacer]

Holy shit, sure glad I don't have to deal with all these issues!!.. eek! eek! :D

[Ratacole]

GofastRacer:
Holy shit, sure glad I don't have to deal with all these issues!!.. eek! eek! :D :D :D :D No shit, Art!!!!! But the funny thing is, is that wideopen 545 just did the same thing eek! . If I would have known I would have sold him mine & bought a new bug catcher smile_sp
[ October 18, 2003, 04:31 PM: Message edited by: Ratacole ]

[GofastRacer]

Yep that would have been the thing to do! :D :D :D

[Badboat1]

9375 is a very good carb with just some minor things that need to be done to it And as Hot said it is a 3 ciruit carb so it easy to tune also the boosters need to be taken out and taken apart and cleaned up allways casting slag on them and in the holes.The ends of the main body need to be milled,to make true.And the venturi area needs to be blended to get the rough line out of it and polished.

[DEL51]

REX, that was funny.By the way,did arianna make any comments after the election? I have a similar carb to the 9375 and i have the annular discharge boosters. I have huge jets and a lot of work with the bleeds and emulsion tubes.They are the 1150's model number 9377. I ended up with alcohol size jets to get it to work right.I was told that these weren't the correct carbs but did not want to spend more money.The carb tuning was 12 hours on the dyno.I did not know about the larger booster.I started out with 98 jets in each corner and I am now at 140 and 153. my air fuel ratio was 12.7 and max egt was 1470 deg. This worked well n the boat and dyno. My fuel consumption at max load and power is 97gph. Would the larger boosters improve fuel efficiency?I am running a 1471 with 11.8 lbs boost on pump gas with an intercooler. 572 cu in. It made 1117 with air filter and 1140 without.Race fuel and 13.8 lbs produced a small gain to 1166 without air filter.engine guy said heads and cam would need to be bigger for more HP.Ty any suggestions?

[GofastRacer]

Badboat1:
9375 is a very good carb with just some minor things that need to be done to it And as Hot said it is a 3 ciruit carb so it easy to tune also the boosters need to be taken out and taken apart and cleaned up allways casting slag on them and in the holes.The ends of the main body need to be milled,to make true.And the venturi area needs to be blended to get the rough line out of it and polished. Just a standard rebuild on any Holley carb!.. :)

[Badboat1]

You know it GoFast I left out you do need to change the air bleed size.I can do one and almost dead on or it is dead on.Guys allways do not understand bigger CID need more jet wrong short crank it pulls more through the booster.

[GofastRacer]

You got that right!.. :D

[Hotcrusader76]

Originally posted by DEL51
I have huge jets and a lot of work with the bleeds and emulsion tubes.They are the 1150's model number 9377. I ended up with alcohol size jets to get it to work right.I was told that these weren't the correct carbs but did not want to spend more money.The carb tuning was 12 hours on the dyno.I did not know about the larger booster.I started out with 98 jets in each corner and I am now at 140 and 153. my air fuel ratio was 12.7 and max egt was 1470 deg. This worked well n the boat and dyno. My fuel consumption at max load and power is 97gph. Would the larger boosters improve fuel efficiency?I am running a 1471 with 11.8 lbs boost on pump gas with an intercooler. 572 cu in. It made 1117 with air filter and 1140 without.Race fuel and 13.8 lbs produced a small gain to 1166 without air filter.engine guy said heads and cam would need to be bigger for more HP.Ty any suggestions?
These particular carb model numbers looks good?
Your stock annular boosters could have a fuel passage size from 0.150"-0.158" depending on tolerance variances, which is normally stock size unless modified. I've seen some clients virgin Dominators mix-matched in fuel passage size as much as 0.009". You definitely need to have a larger booster with this blown application.
Nonetheless by stepping up into a larger fuel passage and possibly the 12-hole booster design your overall fuel curve won't need to be as high. You might see a 10-15% drop in jet size and less loading up on the bottom-end. From reading your post it looks like they might have enlarged your idle air-bleeds in order to kill the signal and lean her out some.
All in all the Dyno and EGT proved to show your system is within calibration from what you posted, but at what RPM. Was your Dyno sheet consistent throughout the powerband? Granted you're correct on your numbers, it's all a balance within the circuitry for a perfect A/F.
Something you might want to consider at those projected higher boost levels and after your new cam and head swap is to have those Dominator's throttleplates enlarged. This is similar to the design theory of adding 850 baseplates to 750 mainbodies to increase the CFM marks of the 950DP. You could consider enlargeing the plates to 2.20" which requires machineing. This will increase the booster signal when going to a smaller booster diameter and taller skirt (not wider).
Hope this sheds more light than darkness...;)