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Discussion Starter · #1 · (Edited)
I'm considering trying a Holley carburetor. When I look online, there are a plethora of different series with different names. I would appreciate it if some Holley nerds could help me to differentiate so I could decide on a specific carb. (I would like to keep this discussion about Holley carburetors and not make it a debate about other carburetors or EFI, please.)

In my years of twisting wrenches, I have worked with Autolite, Edelbrock, Summit Racing and Quadrajet carburetors. Strangely, I've never run a Holley. My brother was always a Holley guy, but to be honest, he never knew enough to calibrate or fix them. (Doggone brother. He's no help! :D )

My car is a 1970 Mach 1:
  • 351 Cleveland
  • Aussie heads
  • Custom, solid lifter cam that pulls to 6200 RPM
  • 3.70 rear gear
  • TKO 600 trans
  • Factory distributor calibrated by Mustang Barn
  • Shorty headers with dual exhaust
Objectives are mostly street driving with occasional autocross, time attack and drag strip events for fun and not serious competition. I live at over 6,000 feet above sea level, so tunability is a high priority.

I would like a mechanical secondary double-pumper with annular boosters, probably 650 CFM, but there are a lot of options. I've seen some remanufactured "HR Series" carbs online that look appealing. The pictures suggest they have annular boosters, but the description doesn't mention it. They also have a Quick Fuel label. Interesting, but I'm confused compared to other models that appear to have similar features and specs.

Thanks!
 

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Why do you want to replace your existing Summit carb? What are you trying to gain that the Summit doesn't offer? Not trying to start a debate between the two brands, just legitimately curious why you want to switch.

I'm still waiting on my Edelbrock intake manifold to show up so I can finally mount my new Summit carb that I bought based on your (and others) recommendation.
 

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Discussion Starter · #3 ·
Why do you want to replace your existing Summit carb? What are you trying to gain that the Summit doesn't offer? Not trying to start a debate between the two brands, just legitimately curious why you want to switch.

I'm still waiting on my Edelbrock intake manifold to show up so I can finally mount my new Summit carb that I bought based on your (and others) recommendation.
Fair question. The Summit is a great carb. I want to run 650 or 670 CFM and that's not available with a Summit carb. I also want to move the fuel inlet to the driver side to shorten the fuel line between the pump and carb; not possible with the Summit carb. (Vapor lock is a big problem at my altitude.) I'm also having problems getting the Summit carb to idle below 1,000 RPM. This could be a factor of altitude or cam; I'm not sure.

This reminds, me: the Holley carb should have the ability to run the fuel line on the driver side. I'm not sure if all Holley carbs have this feature.
 

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From what I am to understand Clevelands like more CFM vs less. IIRC some came from the factory with 800+ CFM carbs. From my looking, if you are looking for annular boosters, Quick Fuel is your Holley variant.
 

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I spent several months pondering which carb to run with a Lunati street cam. My patience paid off, as I am extremely happy with my choice. Quick Fuel Brawler. You want this carb! As you probably know, this is essentially a Holley. But aluminum instead of zinc. Whole 5 lbs less! Can be plumbed either side. Adjustable air bleeds, a must have. No annulars though. Down leg boosters. Adjustable power valve channel restrictions. Fuel level sight windows, not plugs. After dialing mine in with the help of A/F meter, my car runs like a raped ape at low, mid and high RPM. And really good fuel economy. I went race, no choke, but I have to poke the gas till it warms up. Vac seconds, for fuel economy. Double pumpers are nice though.
 

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If you have a performance engine, a custom carb is the way to go IMO.

I run one of Lukes Holley carbs tuned to my engine. Other than sending it back to him every few years or so for rebuilds (not really needed on non racecars), it is flawless!

Luke is a friend, a good drag racer and a helluva race engine builder.



Mark
 

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Discussion Starter · #7 · (Edited)
I spent several months pondering which carb to run with a Lunati street cam. My patience paid off, as I am extremely happy with my choice. Quick Fuel Brawler. You want this carb! As you probably know, this is essentially a Holley. But aluminum instead of zinc. Whole 5 lbs less! Can be plumbed either side. Adjustable air bleeds, a must have. No annulars though. Down leg boosters. Adjustable power valve channel restrictions. Fuel level sight windows, not plugs. After dialing mine in with the help of A/F meter, my car runs like a raped ape at low, mid and high RPM. And really good fuel economy. I went race, no choke, but I have to poke the gas till it warms up. Vac seconds, for fuel economy. Double pumpers are nice though.
What is specific about the Brawler series?
 

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Discussion Starter · #8 ·
If you have a performance engine, a custom carb is the way to go IMO.

I run one of Lukes Holley carbs tuned to my engine. Other than sending it back to him every few years or so for rebuilds (not really needed on non racecars), it is flawless!

Luke is a friend, a good drag racer and a helluva race engine builder.



Mark
If I was racing, I would definitely go with a custom carb. In my case, I think that's more effort and cash than necessary.
 

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Discussion Starter · #9 ·
From what I am to understand Clevelands like more CFM vs less. IIRC some came from the factory with 800+ CFM carbs. From my looking, if you are looking for annular boosters, Quick Fuel is your Holley variant.
I'm pretty sure the largest carb on a factory Cleveland was the Boss 351 with a 750 Holley. If I had 4V heads, like the Boss 351, I would probably go with a 750. The Cleveland Aussie heads have 2V ports with closed combustion chambers. (My static compression is around 10.7:1.) The 2V ports are still pretty huge, but not cavernous like the 4V heads.
 

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What is specific about the Brawler series?
The Brawler series is the economy line of the top Q series carb. Costs quite a bit less, but still relatively high caliber. Unless you are a top level racer, it's all you need.
 

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As you know, stock 2V Cleveland heads still have good size ports and valves. With shifting at 6,000 rpm on a 351C you're moving a lot of air. I would strongly suggest looking at a 750 cfm carb. I run a Holley 830 cfm carb on my 393w. My 830 is a double pumper with four corner idle mixture adjustment
 
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I'm considering trying a Holley carburetor. When I look online, there are a plethora of different series with different names. I would appreciate it if some Holley nerds could help me to differentiate so I could decide on a specific carb. (I would like to keep this discussion about Holley carburetors and not make it a debate about other carburetors or EFI, please.)

In my years of twisting wrenches, I have worked with Autolite, Edelbrock, Summit Racing and Quadrajet carburetors. Strangely, I've never run a Holley. My brother was always a Holley guy, but to be honest, he never knew enough to calibrate or fix them. (Doggone brother. He's no help! :D )

My car is a 1970 Mach 1:
  • 351 Cleveland
  • Aussie heads
  • Custom, solid lifter cam that pulls to 6200 RPM
  • 3.70 rear gear
  • TKO 600 trans
  • Factory distributor calibrated by Mustang Barn
  • Shorty headers with dual exhaust
Objectives are mostly street driving with occasional autocross, time attack and drag strip events for fun and not serious competition. I live at over 6,000 feet above sea level, so tunability is a high priority.

I would like a mechanical secondary double-pumper with annular boosters, probably 650 CFM, but there are a lot of options. I've seen some remanufactured "HR Series" carbs online that look appealing. The pictures suggest they have annular boosters, but the description doesn't mention it. They also have a Quick Fuel label. Interesting, but I'm confused compared to other models that appear to have similar features and specs.

Thanks!
First off, the engine is modified, so the general rules of what cfm is correct, is out the window, AKA not applicable.
My modified 289, built to HiPo specs, but using modified 351W iron heads, likes the 725 cfm Holly I've had on there since the the engine was built in 1983.
Hollys are easy to rebuild, I taught myself. I started rebuilding them, Carter AFBs and AVS carbs and sold a few now 'n then.
I believe U'll need a 750 cfm carb for your application.
And, double pumpers are best left to a race application, especially when used on an engine with an automatic transmission.
You don't need to buy a 400/500 dollar carburetor. Mine is probably 40 -50 years old. Cost me $25 @ an auto flea market, plus $40 for a NAPA universal rebuild kit. I rebuilt it again about 20 years ago, using the same NAPA kit and haven't touched it since.
A Holly, model 4150?, LIST #3310, 750 cfm carb would work good for you. 🙂
 

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Discussion Starter · #14 ·
First off, the engine is modified, so the general rules of what cfm is correct, is out the window, AKA not applicable.
My modified 289, built to HiPo specs, but using modified 351W iron heads, likes the 725 cfm Holly I've had on there since the the engine was built in 1983.
Hollys are easy to rebuild, I taught myself. I started rebuilding them, Carter AFBs and AVS carbs and sold a few now 'n then.
I believe U'll need a 750 cfm carb for your application.
And, double pumpers are best left to a race application, especially when used on an engine with an automatic transmission.
You don't need to buy a 400/500 dollar carburetor. Mine is probably 40 -50 years old. Cost me $25 @ an auto flea market, plus $40 for a NAPA universal rebuild kit. I rebuilt it again about 20 years ago, using the same NAPA kit and haven't touched it since.
A Holly, model 4150?, LIST #3310, 750 cfm carb would work good for you. 🙂
Thanks. I have a manual trans and a 3.70 rear gear. So, I think a double pumper and mechanical secondary is appropriate.
 

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Discussion Starter · #15 · (Edited)
As you know, stock 2V Cleveland heads still have good size ports and valves. With shifting at 6,000 rpm on a 351C you're moving a lot of air. I would strongly suggest looking at a 750 cfm carb. I run a Holley 830 cfm carb on my 393w. My 830 is a double pumper with four corner idle mixture adjustment
Thanks, Magnum. Do you think a 750 would still work at 6,700 feet? If I go with a 750, I will definitely want annular boosters. I really like the way those work at part throttle/cruise. And they're especially helpful with larger carburetors.
 

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Every modern Holley I’ve used ran better with the floats lowered to less than the factory recommended height. Much better response off-idle.

I especially like the 650 cfm Street HP series

thats my only observation

Z
 

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Thanks, Magnum. Do you think a 750 would still work at 8,700 feet? If I go with a 750, I will definitely want annular boosters. I really like the way those work at part throttle/cruise. And they're especially helpful with larger carburetors.
I think a 750 would work well on your car. Altitude is not a factor in carb sizing accordingto info I've read. Just jetting.
 

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Discussion Starter · #18 · (Edited)
I think a 750 would work well on your car. Altitude is not a factor in carb sizing accordingto info I've read. Just jetting.
Thanks. I appreciate that. Also, should have been 6,700 feet. I'm not in Leadville. :)

Looks like this Quick Fuel would fall into what you're recommending:


I was looking at this carb when I was building my car, but the price scared me off. By the time I bought the fuel inlet, I was getting to $1,000 territory. I don't have all the other things going on now, so maybe that would be doable.

Can you tell me about the 4-corner idle? I've never had a carb with that feature. (???)
 

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Discussion Starter · #19 ·
Every modern Holley I’ve used ran better with the floats lowered to less than the factory recommended height. Much better response off-idle.

I especially like the 650 cfm Street HP series

thats my only observation

Z
Thanks. Looks like there's a new version of that carb, but it doesn't have annular boosters. Good to know about the float settings.
 

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1970 Ford Mustang, Windsor 302 V8, C4 Automatic Transmission, Holley 4150C Carburetor
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I hope that this helps, but I run a Holley 4150C. I use it on a mid 80s 302 V8 that was swapped into the car by a previous owner. It does really well and doesn't need to be adjusted much.
 
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