Is 1150 Dominator too big?
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From: Stafford VA
Is 1150 Dominator too big?
Eagle forged 496 stroker crank
Eagle billet main caps
Eagle H-beam rods
Keith Black 10:1 forged pistons
Hugely ported Chevy rectangle heads with studs
Ultradyne, mechanical roller cam 258/272 @ .050", 112lsa, .670/.680 lift
Edelbrock C324 low profile single plane - I think that's the right model, older style that's no longer made but specifically requested by the motor builder. I bought it and sent it to him, he port matched it to the heads.
Harland Sharps roller rockers
Hooker sidepipes with Max Flo inserts
Going into a 1970 4 speed 4.11 rear car with no options (PS, PB, AC, etc). Probably going to use an aluminum flywheel and CF MF ceramic clutch.
I am taking the car to an engine dyno for break in and tuning as soon as the MSD billet distributor arrives. The carb was part of a package deal on the motor and I'm a little concerned that it's too big, don't want to pay the shop to tell me they can't dial it down. Thoughts?
Eagle billet main caps
Eagle H-beam rods
Keith Black 10:1 forged pistons
Hugely ported Chevy rectangle heads with studs
Ultradyne, mechanical roller cam 258/272 @ .050", 112lsa, .670/.680 lift
Edelbrock C324 low profile single plane - I think that's the right model, older style that's no longer made but specifically requested by the motor builder. I bought it and sent it to him, he port matched it to the heads.
Harland Sharps roller rockers
Hooker sidepipes with Max Flo inserts
Going into a 1970 4 speed 4.11 rear car with no options (PS, PB, AC, etc). Probably going to use an aluminum flywheel and CF MF ceramic clutch.
I am taking the car to an engine dyno for break in and tuning as soon as the MSD billet distributor arrives. The carb was part of a package deal on the motor and I'm a little concerned that it's too big, don't want to pay the shop to tell me they can't dial it down. Thoughts?
Drifting
Joined: Aug 2004
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From: Lubbock TX
Only if an 850DP is too big on a 283!
1050 would have been a lot better, but still on the big side.
I've seen a 496 run with the sister intake (427C) and an 850DP, it could rev to 7 grand and had almost unreadable vacuum at WOT.
1050 would have been a lot better, but still on the big side.
I've seen a 496 run with the sister intake (427C) and an 850DP, it could rev to 7 grand and had almost unreadable vacuum at WOT.
Team Owner
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
I can't figure out which intake you are talking about. But none of the older EDL manifolds were performance enhancers when compared to tuned runner design single planes..... worthless crap all those Torquer, taranchula, scorpian IMO - The builder is stuck with 30 year old thinking. The cam numbers sound like some pipe dream off of Desk top dyno that rewards big split duration exhaust numbers.
Is this a pure drag car? Because 4.11, 1050 cfm, low compression for cam choice is not going to be a good setup
Is this a pure drag car? Because 4.11, 1050 cfm, low compression for cam choice is not going to be a good setup
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From: Stafford VA
I can't figure out which intake you are talking about. But none of the older EDL manifolds were performance enhancers when compared to tuned runner design single planes..... worthless crap all those Torquer, taranchula, scorpian IMO - The builder is stuck with 30 year old thinking.
Not sure what you mean by not being a good setup, not a good performance package or just too high strung for the street?
Drifting
Joined: Aug 2004
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From: Lubbock TX
Jim Moore did a 555 build and tried out this exact C454 intake. Everyone was surprised, it lost very little when compared to a street single plane. They have huge honkin' runners, much bigger than even the new air gap. It'll fit under the hood and look stock - except for that suck-a-squirrel-off-the-track Dominator on top of it 
Tech Contributor
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From: At my Bar drinking and wrenching in Lafayette Colorado
We're running a 1050 Dominator on a 407 small block, and dyno numbers and track numbers show that it outperforms 750, 850 and 950 carbs by a significant margin. Most of the dyno time spent on tuning it involved high speed air bleeds - the jetting was good out of the box. High speed bleeds were used to tune for altitude.
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From: Who says "Nothing is impossible" ? I've been doing nothing for years.
I don't have a problem with the Dominator, it is the compression ratio that I think should be raised a bit with that cam. The Dominator can be dialed in if your machinist has been around doing this for 30 years
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From: Corsicana, Tx
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The old C454 isn't all that bad. Best thing is it fits under the hood! I did test it on a 555" motor using Dart 335's and a solid flat tappet cam. The intake was untouched and there was a huge mismatch in port sizes from intake into heads.
Even though it was designed for motors at least 100" smaller it was within 15-20 HP of a VERY high $$$ Wilson ported Vic Jr and a HP 1000 carb. This takes nothing from the Wilson intake, because even it was too small for the 555" combo we had. I'm sure a few hours of port work would have helped the C454 a lot. It made 740HP @6200 with the cam we had and was hanging on well past 6500.
That cam choice may well have to do with whatever those head flow. Looks like Harold was trying to crutch the exhaust side some.
There's lots of ways to build a cam to work....look at some of Jay Allen's stuff. Almost always huge splits on exhaust....and they always make power. Just depends on the rest of the combo and that other lobe you've paired it with.
I'd probably throw a little more compression at it too as well as some 1.8 rockers on intake side.
Depending on which Dominator you have...it will likely take some time to make it work smoothly on the street...but it can be done. I like big carbs!!
JIM
Even though it was designed for motors at least 100" smaller it was within 15-20 HP of a VERY high $$$ Wilson ported Vic Jr and a HP 1000 carb. This takes nothing from the Wilson intake, because even it was too small for the 555" combo we had. I'm sure a few hours of port work would have helped the C454 a lot. It made 740HP @6200 with the cam we had and was hanging on well past 6500.
That cam choice may well have to do with whatever those head flow. Looks like Harold was trying to crutch the exhaust side some.
There's lots of ways to build a cam to work....look at some of Jay Allen's stuff. Almost always huge splits on exhaust....and they always make power. Just depends on the rest of the combo and that other lobe you've paired it with.
I'd probably throw a little more compression at it too as well as some 1.8 rockers on intake side.
Depending on which Dominator you have...it will likely take some time to make it work smoothly on the street...but it can be done. I like big carbs!!
JIM
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
My mistake, the intake is a C454 and it's a dual plane, not single. I don't doubt the builder is stuck with at least a little 30 year old thinking, he's been building chevy race motors as his full time job for longer than that. Is the C454 a better choice?
Ultradyne spec'd the cam based on the rest of the motor and the car. Is there something you would change about the cam profile?
Not sure what you mean by not being a good setup, not a good performance package or just too high strung for the street?
Ah, much better.... I thought that you had some junky old low rise single plane. Like Jim said: large split on the exhaust duration is usually for a very restrictive exhaust.
After 20 years of driving around with OD and 4.11 I changed to 3.55 rear. A 700 hp like yours will suck with 4.11 and 4 speed. Your street tires will limit low speed WOT in the first 2 gears. You will spend your time doing very quick shifts instead of getting to feel the power surge that wider gear spacing brings.
I found myself only using the top three gears of my 5 speed.
As for big carbs. I'll take my great drivability and except the minor loss on the top end. I like going full throttle at lower rpm and not having it hickup. I actually get good gas mileage
Ultradyne spec'd the cam based on the rest of the motor and the car. Is there something you would change about the cam profile?
Not sure what you mean by not being a good setup, not a good performance package or just too high strung for the street?
Ah, much better.... I thought that you had some junky old low rise single plane. Like Jim said: large split on the exhaust duration is usually for a very restrictive exhaust.
After 20 years of driving around with OD and 4.11 I changed to 3.55 rear. A 700 hp like yours will suck with 4.11 and 4 speed. Your street tires will limit low speed WOT in the first 2 gears. You will spend your time doing very quick shifts instead of getting to feel the power surge that wider gear spacing brings.
I found myself only using the top three gears of my 5 speed.
As for big carbs. I'll take my great drivability and except the minor loss on the top end. I like going full throttle at lower rpm and not having it hickup. I actually get good gas mileage
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From: Stafford VA
Jerry Craycraft built the motor, small shop outside Texarkana that ported a bunch of my 4 stroke drag ATV heads. Old school motor builder but he gets the job done, his ATV heads made shops with flow benches and cnc machines lay awake at night.
The motor was being built for a blown boat and the boat owner ran out of money before the blower was ordered. I got the motor for a steal due to a shared love of Corvettes and the ATV head porting relationship. We changed the cam to run NA but not the pistons, figured it would run OK with lower compression but allow me to add nitrous later. I know the motor can handle a healthy shot but suspect I'll be putting cubic money into the rest of the drivetrain first...
We talked about the sidepipes not being the absolute best choice for performance, that's probably why they went for a little more duration on the exhaust.
Appreciate all the help guys, I'm going to throw the distributor on it and take it to the dyno shop with the 1150. Wish me luck!
The motor was being built for a blown boat and the boat owner ran out of money before the blower was ordered. I got the motor for a steal due to a shared love of Corvettes and the ATV head porting relationship. We changed the cam to run NA but not the pistons, figured it would run OK with lower compression but allow me to add nitrous later. I know the motor can handle a healthy shot but suspect I'll be putting cubic money into the rest of the drivetrain first...
We talked about the sidepipes not being the absolute best choice for performance, that's probably why they went for a little more duration on the exhaust.
Appreciate all the help guys, I'm going to throw the distributor on it and take it to the dyno shop with the 1150. Wish me luck!
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From: Stafford VA
If I take it to the dyno shop without changing the intake rockers, what might I see on the graph that would tell me it wants more intake lift? Lower than expected peak numbers? Power dropping off too fast - peaky? Less than impressive bottom end? Or??
I've read your posts, know that you know your stuff, and greatly appreciate your insight.
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From: Corsicana, Tx
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Without knowing the flow characteristics of the heads..it's hard to tell how much 1.8 rockers will help. But with a .670" cam now..once you take out lash you're not too huge at the valve. Added intake lift usually helps...more incremental than big jumps. They also add a couple degrees of effective duration usually so that helps some. you can try tightening the last down to like .010" on the intakes or so and see if it helps. That will give you an idea.
The big exhaust duration *can* pull TQ out of a combo by opening valve too early...but it's a balancing act if the cylinder can't get cleaned out enough.
I wouldn't lose much sleep over compression. For sure it would like more....but if N20 is in the picture then that takes care of those problems. The added ex duration will help with the N20 also.
Let us know how it does!
JIM
The big exhaust duration *can* pull TQ out of a combo by opening valve too early...but it's a balancing act if the cylinder can't get cleaned out enough.
I wouldn't lose much sleep over compression. For sure it would like more....but if N20 is in the picture then that takes care of those problems. The added ex duration will help with the N20 also.
Let us know how it does!
JIM
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From: Graceland in a Not Correctly Restored Stingray
Don't have dyno numbers, but I've run a progressive 1050 Dom and C454 (still have the intake ) on a moderate street 427 BB with impressive results, so IMHO a properly tuned 1150 shouldn't be too much carb for a strong 496. I'd suggest staying away from a 1-to-1 on the street tho (BTDT 
).
As for the large split between intake and exhaust profiles I'm on board with what Jim says about walking a fine line, but do keep in mind that this can sometimes cover up a significant enough percentage of a deficiency in BB exhaust port flow as to make using such a crutch a good call, especially if you end up spraying it. FWIW, I'm not past doing this vs. more exhaust port work myself if I find I'm not completely satisfied with the solid roller 427 BB build up I'm currently on.
) on a moderate street 427 BB with impressive results, so IMHO a properly tuned 1150 shouldn't be too much carb for a strong 496. I'd suggest staying away from a 1-to-1 on the street tho (BTDT ).As for the large split between intake and exhaust profiles I'm on board with what Jim says about walking a fine line, but do keep in mind that this can sometimes cover up a significant enough percentage of a deficiency in BB exhaust port flow as to make using such a crutch a good call, especially if you end up spraying it. FWIW, I'm not past doing this vs. more exhaust port work myself if I find I'm not completely satisfied with the solid roller 427 BB build up I'm currently on.
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From: Stafford VA
After rebuilding the motor because the original builder "forgot" to clean the block before assembly, finally spent some quality time on the engine dyno.
The 1150 Dominator I have is too big for this motor, we couldn't get the lower rpm AF above 11:1. New builder recommended a 1050 Dominator which made exactly the same HP as the 1150 at 6400 rpm but didn't foul the plugs below 3000 rpm.
Motor liked 39 degrees of total timing and could bring it all in by 2800 rpm with no pinging on 93 octane.
The pistons are 9:1 forged JE instead of 10:1 forged Keith Black but aside from the "extra" gunk in the oil passages, no other surprises from what I was sold by the original builder.
600HP at 6400 rpm, 596 HP at 6500 rpm (just rolling over), and 500+ HP from 4000 rpm up. I was a little disappointed with the numbers until the dyno operator said he keeps his dyno on the conservative side of calibration, said he never wants a motor customer to dyno less HP than he sold them. The guy builds billet big blocks for a living and showed me dyno sheets of other shop's advertised 1900 HP motors reading 1705 HP on his dyno. He said that on any other engine dyno, mine is a solid 650HP motor.
Now that I have a respectable motor, time for clutch and flywheel decisions.
The 1150 Dominator I have is too big for this motor, we couldn't get the lower rpm AF above 11:1. New builder recommended a 1050 Dominator which made exactly the same HP as the 1150 at 6400 rpm but didn't foul the plugs below 3000 rpm.
Motor liked 39 degrees of total timing and could bring it all in by 2800 rpm with no pinging on 93 octane.
The pistons are 9:1 forged JE instead of 10:1 forged Keith Black but aside from the "extra" gunk in the oil passages, no other surprises from what I was sold by the original builder.
600HP at 6400 rpm, 596 HP at 6500 rpm (just rolling over), and 500+ HP from 4000 rpm up. I was a little disappointed with the numbers until the dyno operator said he keeps his dyno on the conservative side of calibration, said he never wants a motor customer to dyno less HP than he sold them. The guy builds billet big blocks for a living and showed me dyno sheets of other shop's advertised 1900 HP motors reading 1705 HP on his dyno. He said that on any other engine dyno, mine is a solid 650HP motor.
Now that I have a respectable motor, time for clutch and flywheel decisions.
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From: Fremont CA
I would have sold you a C454 intake and a RARE 1050 Dominator that I took off a LS-6 Chevelle back in the early 90's for $550. This thing was pretty dialed in on that car (it ran 11.80's with that set-up.)
The Domiantor carb is a list#9375 that Holley still carries but mine has vacuum ports for street use and a mechanical choke set-up, I have only seen one other like it in real life but, they used to be in the Motion Performance ads back in the 70's. This set-up is some pretty RARE STUFF that runs well, you machinist is a "old school" guy like myself that knows some old combinations were pretty good and withstand the test of time
We took the C454/Holley combo off the Chevelle to restore it to stock, nice black/white stripes LS-6 coupe I helped the owner with back then. Also took off Lakewood ladder bars, air lift bags inside the rear coil springs, and raised front spindles for the "mile high" look. Car was a very fast street racer back in the 70's, days of my youth
The Domiantor carb is a list#9375 that Holley still carries but mine has vacuum ports for street use and a mechanical choke set-up, I have only seen one other like it in real life but, they used to be in the Motion Performance ads back in the 70's. This set-up is some pretty RARE STUFF that runs well, you machinist is a "old school" guy like myself that knows some old combinations were pretty good and withstand the test of time
We took the C454/Holley combo off the Chevelle to restore it to stock, nice black/white stripes LS-6 coupe I helped the owner with back then. Also took off Lakewood ladder bars, air lift bags inside the rear coil springs, and raised front spindles for the "mile high" look. Car was a very fast street racer back in the 70's, days of my youth
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Is that the older Dominator with the tall throats above the carb?
JIM
JIM
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From: League City Tx
Wow...a Dominator with a choke......never seen that before. That old carb is probably worth some jack...
Here is a pic of one that some GM Engineers were testing on a ZL1 vette back in 69'....Car ran 10.80s back then...
