going from 4150 to a dom

[fishman1]

I have a sbc 383 which has a holley 4150 reworked which has around 950 cfm the venturis are 1.42 and the base plate is throttle bore is 1.750 and off my dyno sheet and my 1/4 numbers from my 1/8 mile numbers i need a bigger carb

yesterday run example 1/8 time..........6.363 sec
1/4 mile ..........10.12 sec

i have a friend that is going to lend me his 1050 dominator and my question is should i run the same jets as i have in smaller carb now and how about air bleeds............thanks in advance guys

[ashbros]

I have always ran a 1050 on all small blocks.

Its a short clip, but in the first portion of this video you'see the truck running on gas using a 1050,

As you will see from the exhaust, its not running rich at all, no black puff of smoke

http://www.racingjunk.com/video_gallery/60574

You shoud not have a problem at all.

This was a flat top 350, good set of heads w/ lots of work and a 5 something lift cam, 2" exhaust. It wasn't much. With the little 142 blower it ran 10.10's. Without the blower it ran 10.70's

[jmarksdragster]

No, the metering is different on the carbs. Is it a factory Holley, if so, what model #?

[ashbros]

Also if your going from a 4150 series carb to a dominator you will need a dominator flanged intake..

[elkymann]

Well, here is what I would do, I would put the stock box size jets in it, turn all the idle screws in until they stop and then back them all out 1.5 turns, turn your idle screw out until it is off the throttle, then turn it back in until it just touches it, and turn that in up to 2 turns and that should get you running at idle, thenreadjust from there to your idle you may have had before. Is this a 3 circuit car??? If so, you should have no problem with this carb running. Make sure it has the jet extensions, notched flaot in the back bowl and make sure it is clean inside and out. After you hook it up, make sure you have full throttle fill the bowls up and go like hell :D

x2 on the adapter also.

[fishman1]

The carb i have now is actually a 850 cfm holley with a proform 950 body but my carb guy has reworked the carb so the venturies are bigger but still to small for my car off of numbers the car runs especially in the top end and on the dyno..........i have jet extensions and notched floats and yes when i borrow ny buddys dom 1050 i will check it out ..........not sure if it is a 3 circuit carb or 2 as i don't have it in my hands yet........i also bought a adatper for a dom car b to a 4150 style my intake is............right now i am running front jets #82 with power valve and back #88 with no power valves...........i know i am falling off in the top end and not sure how to jet when i put on the dom carb if i should go bigger or leave the same and the same with the air bleeds..............thanks

here is a video of the car
http://www.youtube.com/watch?v=MlNsixubZxs

[fishman1]

I phoned holley today to get their opinion on running a dominator instead of a holley 4150 and going up to a 1050 cfm on my motor..........well this is what he told me that that carb would kill my motor that i need a 4150 750 cfm carb..........well i couldn't argue with him as he was set..........i have my dyno numbers and it is showing in the top end that the car is running out of carb and also from my 1/8 mile times to my 1/4 times there is something wacko...........he then told me that probably my fuel system wasn't delivering enough fuel or i needed more jet............. i can post my dyno numbers

rpm torque hp manvac hg

4900 510 480 .81
5000 516 494 .84
5100 521 509 .93
5200 522 515 .95
5300 525 523 .98
5400 518 531 1.01
5500 516 541 1.05
5600 513 548 1.08
5700 510 553 1.11
5800 507 560 1.15
5900 504 566 1.19
6000 501 572 1.23
6100 496 576 1.27
6200 495 584 1.31
6300 490 587 1.35
6400 484 590 1.37
6500 476 592 1.40
6600 472 594 1.40
6700 466 595 1.41
6800 457 592 1.43
6900 449 590 1.45
7000 441 588 1.47

give me your thoughts guys and thanks in advance

[chevyfireball]

I would agree with the Holley guy. 1050 is way too big for a 383ci. Too many guys make the mistake of going too big on the carb. I ran a 1050 on my 572ci after finding an 1150 too big. Check your fuel delivery.

[OneBadGMC]

How do you know it's the carb? Might be cam or heads?

I wouldn't run a 950 or 1050 on a 383. Not unless we're talking about 15:1 and a .750 cam with little chief heads.

At 8000 RPM and 100% VE, that motor is only going to use 887 CFM at most.

At 80% VE, it's only going to need 710 CFM.

The 4150 carb you have now is plenty.

From 6500 to 7000 the power flattens out and the torque drops. What cam/heads/intake are on it?

[TS1955]

How do you know it's the carb? Might be cam or heads?

I wouldn't run a 950 or 1050 on a 383. Not unless we're talking about 15:1 and a .750 cam with little chief heads.

At 8000 RPM and 100% VE, that motor is only going to use 887 CFM at most.

At 80% VE, it's only going to need 710 CFM.

The 4150 carb you have now is plenty.

From 6500 to 7000 the power flattens out and the torque drops. What cam/heads/intake are on it?

X2...My 434 @ 7500 only requires a 941 cfm carb & I have 950 Barry Grant on it. JMO

TS1955

[Tod74]

I have a 1050 on a 540 with a .737 lift roller and brodix heads.
I can't see you needing a 1050 on a 383 but that's just my opinion.

[FullTimeRacing]

I have a 1050 on my 360 cid ran the same as the 850 ,but alot cleaner.

just saying.

[Tod74]

I have a 1050 on my 360 cid ran the same as the 850 ,but alot cleaner.

just saying.

wow. I Would have bet money it would slow down. Was the 850 a piece of crap? just asking.

[FullTimeRacing]

It is a barry grant and was verry inconsistant.

would run great one pass,pop once or twice on the next

put the dom on ran the same just no pop. it also small jets at frist and ran the same . Now has stock jets and i think it will pickup this fall.

I just want to be consistant.

[fishman1]

How do you know it's the carb?


From 6500 to 7000 the power flattens out and the torque drops. What cam/heads/intake are on it?

The heads are afr cnc 210's 64 cc and the short turn radius has been cleaned up they flowed 298 cfm @ .700 lift..

the cam is a solid roller comp with 268 and 272 duration with .634 lift

the intake is a super victor that has been ported by larry meaux.

update

i decided to look at my fuel delivery so i firs of changed my feul filter on my suction side to a good wix filter........phoned aeromotive to find out how much my pump will take to pump 1 galoon.

So i took the line off before it goes into the regulator and put it in a gas can and got my son with a stop watch and started the test........i was told it will take 26.7 seconds to get a galoon....well it is no problem as it pumped a galoon which equates to 138 galoons per hour.

So then i phoned holley and told them my problem and what i wanted to now was what needle and seats should it have he told me i should have .120 so i took out the ones in it and they .097 and replaced them with the .120 after this i had to lower my fuel pressure as it jumped up to 9 psi from 8 psi wierd what ever..................i am hoping for the cheap fix and maybe all what was wrong was the needle wouldn't let enough fuel in...........fingers crossed

[OneBadGMC]

It is a barry grant and was verry inconsistant.

would run great one pass,pop once or twice on the next

put the dom on ran the same just no pop. it also small jets at frist and ran the same . Now has stock jets and i think it will pickup this fall.

I just want to be consistant.

BG... That says it all. Probably has metal shavings floating around in the carb that you can't see without taking the emulsion tubes out.

[OneBadGMC]

How do you know it's the carb?


From 6500 to 7000 the power flattens out and the torque drops. What cam/heads/intake are on it?

The heads are afr cnc 210's 64 cc and the short turn radius has been cleaned up they flowed 298 cfm @ .700 lift..

the cam is a solid roller comp with 268 and 272 duration with .634 lift

the intake is a super victor that has been ported by larry meaux.

update

i decided to look at my fuel delivery so i firs of changed my feul filter on my suction side to a good wix filter........phoned aeromotive to find out how much my pump will take to pump 1 galoon.

So i took the line off before it goes into the regulator and put it in a gas can and got my son with a stop watch and started the test........i was told it will take 26.7 seconds to get a galoon....well it is no problem as it pumped a galoon which equates to 138 galoons per hour.

So then i phoned holley and told them my problem and what i wanted to now was what needle and seats should it have he told me i should have .120 so i took out the ones in it and they .097 and replaced them with the .120 after this i had to lower my fuel pressure as it jumped up to 9 psi from 8 psi wierd what ever..................i am hoping for the cheap fix and maybe all what was wrong was the needle wouldn't let enough fuel in...........fingers crossed

Would be nice if it was that simple.

[jmarksdragster]

We ran a 9375 1050 on a dish piston, hydraulic cam, vortec head 406. It was faster than an 800 and deadly consistent. The converter did stall about 5000, which helped a bit. I also ran a 1250 on a 447 SBC, a tenth faster and 20 HP more on the dyno, made as much torque 1000 RPM below peak torque and made more after that than a 1050. If you have enough converter and gear, a bigger carb (within reason) can usually be tuned to work better. Fish, no reason you cant get the 1050 to work good on yours, just realize an out of the box Dominator will usually need some work to get right, some models more than others.

What model # is it and is it an HP model or earlier Dominator?

[fishman1]

We ran a 9375 1050 on a dish piston, hydraulic cam, vortec head 406. It was faster than an 800 and deadly consistent. The converter did stall about 5000, which helped a bit. I also ran a 1250 on a 447 SBC, a tenth faster and 20 HP more on the dyno, made as much torque 1000 RPM below peak torque and made more after that than a 1050. If you have enough converter and gear, a bigger carb (within reason) can usually be tuned to work better. Fish, no reason you cant get the 1050 to work good on yours, just realize an out of the box Dominator will usually need some work to get right, some models more than others.

What model # is it and is it an HP model or earlier Dominator?
jmark

I still haven't recieved the carb from my friend as he lives in a diffrent town and usually just see him at the track, well he blew up his motor so he was suppose to give it to another friend but he hasn't........i have another friend with one i can try but am not sure what model it is.......right now i am usuing #82 jets in front and #88 in back so should i jet the dominator the same and i imagine it has stock air bleed so it could be a crap shoot

[andybyrd]

Fishman1. these guys are telling you Straight up and they are right. You may go quicker with a 750. Story- 1 month ago I went through tis same thing it's posted on here. I have a 434 -666 H/P 15 to 1 comp. it had a 950 and ran 6.20 in the 1/8 and I thought it would run faster with a good Dom. well NOT I bought the HP Dom. and a brodix intake and no matter what I did I could not get it to run any faster with it matter of fact it slowed it down to 6.33 and that was it. $1400.00 down the tolit. I put a dart intake and a new 950 HP back on it and droped my octane down from 114 to 112 and now it's running 6.10 consistently in the 1/8 . TO MUCH CARB IS BAD it cost me a lot of money to learn that lesson.
Be safe and have fun. Andy

[Tod74]

I am curious about the effects of having too high of octane gas.....

[OneBadGMC]

I am curious about the effects of having too high of octane gas.....

Burns too slow, therefore you lose power.

[fishman1]

Well after changes i made ran the car this weekend with no gains, so my cheap fix didn't work ohhhhhh shit. it was worth a try.

On the subject of whether my carb is to big or to small seems to be a mixed answer as i am getting a 50-50 that it is to big and the other half saying a 1050 dom will pick up the top end........in all i conclude the only way i will find out is to find two carbs a 750 and a dom 1050 and try them and then i will know for sure as i think every motor seems to like something diffrent so there probably is no right answer only way is to try and find out for sure......i got my friends dominator this weekend and was looking at it at home and man it is a old bird with no changeable air bleed, the linkage doesn't have the big hole for my linkage and missing the small hole by the base bolt for my plate for my return springs.......have to figure out how to get it to work as as guy i know is renting the track for the day next week so will be able to make a pile of hits for testing and tuning

[jmarksdragster]

If it is a factory Dominator, go to the below Holley reference chart and start at factory settings. 1050's range anywhere from 86 to about 93 depending on the metering setup used and which metering block was used. Later Dominators use more emulsion bleeds, metering was also different between 1 and 2 four barrel carbs, the later HP's are even different still. If it is a modified carb, you need to find out what it came with, some do have lower than 86 to get it right. If you can find out more info, I"ll try to help you get it close.

http://www.holley.com/data/TechService/Technical/Carb Numerical Listing.pdf

[andybyrd]

If you have the Money then putting it to the test is the best thing to do all I was saying that with the 434 in my car the 1050 did slow it down. and that was what everyone told me it would do but I'm a hard headed Guy. but like I said if you have the money try Both that way you know for sure. If you were taking bets on it I would put my money on the smaller Carb though . either way Best of Luck to you. and post the results we would like to see for future inquiries.
and be Safe.
Andy

[fishman1]

If it is a factory Dominator, go to the below Holley reference chart and start at factory settings. 1050's range anywhere from 86 to about 93 depending on the metering setup used and which metering block was used. Later Dominators use more emulsion bleeds, metering was also different between 1 and 2 four barrel carbs, the later HP's are even different still. If it is a modified carb, you need to find out what it came with, some do have lower than 86 to get it right. If you can find out more info, I"ll try to help you get it close.

http://www.holley.com/data/TechService/Technical/Carb Numerical Listing.pdf
jmark

these are the numbers i got off the carb
12r-8795b
l9375
0214

right now it has front jets 88 and rear 89 that is how he was running it

[FullTimeRacing]

this is from mortec.com

9188 780 (F)72,(R)76 6.5,8.5 4150
9375 1050 (F)92,(R)92 --- 4500HP
9375-1 1050 (F)88,(R)88 --- 4500
9377 1150 (F)94,(R)94 --- 4500

[jmarksdragster]

That would be a 9375 1050. If it is a non HP and unmolested, you are in luck. It is the best out of the box 1050 Holley made, the middle/intermediate air bleeds should be open, no brass inserts. Jet it 92 square to start, go up from there. If it slows MPH go back down.


If it is a newer HP 9375, start with 86 square. Be aware that the internal metering is not as good as the older Dominator, and needs a little more work to make it behave. Too much emulsion, and way rich down in the low and mid ranges. If you find it loading up in the burnout and cruising, go up on the intermediate air bleeds. You will probably even be able to remove them, just watch the plugs and jet up as needed.


If someone has worked on it, no way to know what's best without looking at all the passages and doing a little measuring.

[fishman1]

That would be a 9375 1050. If it is a non HP and unmolested, you are in luck. It is the best out of the box 1050 Holley made, the middle/intermediate air bleeds should be open, no brass inserts. Jet it 92 square to start, go up from there. If it slows MPH go back down.


If it is a newer HP 9375, start with 86 square. Be aware that the internal metering is not as good as the older Dominator, and needs a little more work to make it behave. Too much emulsion, and way rich down in the low and mid ranges. If you find it loading up in the burnout and cruising, go up on the intermediate air bleeds. You will probably even be able to remove them, just watch the plugs and jet up as needed.


If someone has worked on it, no way to know what's best without looking at all the passages and doing a little measuring.

Yes mark u r right it has no middle air bleeds they are open.....my friend had it on a 498 bbc and it was jetted 88 front and 89 back......u figure that high of jets our air over here in alberta canada is fairly high good air is we get under 4000 da air..........example would be last weekend best air was 4600 feet with 36% humdity............may we get air around 3000 feet for maybe one meet and then in end of sept in the 3000 feet range

[fishman1]

Got the carb all hooked up and fired up the car tonight......idles fine and if u give throttle part way responds great but if you hammer it to the floor it just chokes out and just about dies.........so i changed the shooters to a bigger shooter to 37 but still does the same......bowl levels are half way up the sight glass............looked at the carb cams and they are white and in hole one.......is this the right color of cam............it seems to me when u punch it is is starving for fuel..........any ideas would be great as my old carb i know i use black cams

[OneBadGMC]

If you hammer the gas and it doesn't backfire out the carb when it 'chokes out', then it's rich, not lean.

Lean hesitates and/or backfires out the carb.

Rich blubbers and/or backfires out the exhaust.

[cepx111]

Excellent point and good explanation> Wj
Damit man, your a pretty fart smeller, I mean pretty smart fellar. 8)
Cp

[Tod74]

the carb is way too big.

[OneBadGMC]

the carb is way too big.

Yeah, I think we told him that back on page 1...

But hey, everyone wants to learn the hard way, right?

[chevynovaman]

WHATS THE BIG DEAL ON 1050... ON MY 383 YEARS AGO WENT FROM A REGULAR 750 DP TO A 750 DOMINATOR AND IT MADE A WORLD OF DIFFERENCE... I WOULD GO WITH THE 750 DOMINATOR AND YOU WILL GET ALOT MORE THROTTLE RESPONSE AND WONT BE TO BIG.... GOOD LUCK...

[fishman1]

the carb is way too big.

Yeah, I think we told him that back on page 1...

But hey, everyone wants to learn the hard way, right?

One bad gmc.....i aprreicate your advice , yes u told me the carb was to big but on the other hand i had as many people tell me that it would work great and that it isn't to big...........that is why i am going to try it i am not bull headed but when i get a 50/50 split i am going for it.

I played with the carb tonight and it is purring like a baby, it was to lean,,,richened up the air fuel ratio and dropped to a 35 squiter and now it has no flat spot............thanks all for your opinions, next week will be the tell tale as how it works.........Friday we have a friend renting the track so i will test and tune then if it doesn't work i will put on my old carb.............proof will be in the pudding

[fishman1]

Well made it to the track this weekend to try out the dominator 1050 of my buddys..........Saturday the air was unreal 4900 feet da............looked at my weather station and with my old carb it said i should run a 10.20 ok got a base to go by, the best the car ran on Saturday was 10.05...it picked up 1 1/2 tenths ok i was happy.....i was going to pull some jet out of the carb as it was rich and my buddy i borrowed the carb off of said hey you want to try my 1050 AEd i have on my car right now and it is faster then the old holley dominator...so i said sure, so we swapped carbs and sunday got up and the air was great 2900 feet but we had a 50-60km head wind yikesssss anyways the best we ran was a 10.002....i was totally surprised as the car picked everywhere......best 60 foots at that track 1.34 from a 1.378 and best 1/8 mile 6.28 from a 6.35 and best et and best mph ..............in all and all i was very happy..............looks like i might have to buy a dominator..............thanks all for the help and info

[prostreetpreach]

ANYTTHING SHORT OF A MAX-EFFORT 383 C.I. WOULD NEVER NEED THAT MUCH FUEL, EXAMPLE OF "MAX-EFFORT":::: 18 DEGREE VALVE ANGLE OR LESS INCLUDING SPLAYED VALVE HEADS, HEAD FLOW NEARING OR SURPASSING 350 CFM ON THE INTAKE SIDE, MEGA COMPRESSION, OVER 700 HONEST HP, ANYTHING SHORT OF THAT AND A 850-950 CFM WILL PUT YOUR 383 IN IT,S PEAK JUST BY USING GENERAL CARB TUNING TECHNIQUES, TO BIG A CARB IS A AGO OLD PROBLEM, I,M GUILTY OF IT MYSELF, GOOD LUCK, JUST THOUGHT I WOULD THROW MY OPINION IN THE MIX, BEEN DOING THIS GAME FOR NEARLY 30 YEARS!!

[bjuice]

don't just buy a domimater...Go with APD or Pro-systems and you will get the Best the Dominater has to offer...it might be few hundred more but well worth the extra ponies their carbs Make.

i have personally had APD custom build me a carb...ran like a banshee !!!