speed demon vs quick fuel
Thread Starter
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
speed demon vs quick fuel
I am curious as to which one everyone thinks is a better carb. i know both are based on holleys but which do you think has improved the design the best. I asked the techs at summit and got recommended each one a separate ocassions.
the speed demon with electic choke, vacuum secondaries and annular boosters
or the SS quick fuel
I have heard about metal shavings in the demons but supposedly those issues have been fixed. I see the quick fuel getting recommended every now and then.
i am going to buy two carbs this xmas, one for the 454 vette and one for the 289 mustang so this is going to be a substantial purchase. i dont want to get screwed. Chances are i will probably be ok with either one but i just wanted to see if anyone had an opinion either way.
the speed demon with electic choke, vacuum secondaries and annular boosters
or the SS quick fuel
I have heard about metal shavings in the demons but supposedly those issues have been fixed. I see the quick fuel getting recommended every now and then.
i am going to buy two carbs this xmas, one for the 454 vette and one for the 289 mustang so this is going to be a substantial purchase. i dont want to get screwed. Chances are i will probably be ok with either one but i just wanted to see if anyone had an opinion either way.
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
Do yourself a favor and stay away from All Barry Grant carbs. They are nothing but trouble. I was happy to get rid of mine. It was full of metal when i got it. and thier tech support is sad. I bought a Pro Systems from Patrick in Michigan. Awesome product great service.
Thread Starter
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
yeah i hear a lot about the infamous metal shavings and unless i see proof somewhere that it has been corrected i wont even consider it . i have never heard of pro systems but what does the made in china thing mean?
is quick fuel made in china?
is quick fuel made in china?
Melting Slicks
Joined: Mar 2008
Posts: 2,336
Likes: 1
From: North Bellmore Ny
St. Jude Donor '09
call barry grant tech support now, its like a whole new company. issues have been resolved go with the Barry Grant you will be Glad you did
Last edited by 400hp427vette; Dec 16, 2008 at 08:19 PM.
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
Baxsom. If your building a daily driver, and need nothing fancy? But an out of the box holley carb. There are lots of aftermarket guys out there building custome tailored carbs. I had one for my camaro race car, and it worked great. But for regular application you cant go wrong with an out of the box hoeely. Just check with your engine builder to determine the correct sizing.
Drifting
Joined: Jan 2001
Posts: 1,841
Likes: 3
From: Halifax, NS, Canada
I am running a Speed Demon 650 with mechanical secondaries on my ZZ4. I am very happen with it. Although I did not have any problems with filings, I did have a couple issues. I was not able to adjust the choke because the three screws holding the choke coil were seized and would not turn without twisting them off. I then realized I didn't even need the choke so I removed the whole mechanism and that resolved that issue. The other thing I discovered was that the throttle plates were not centered properly on the shafts and was causing isle problems. I agree that the technical support line was not very valuable to me either.
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Pro
Joined: Mar 2008
Posts: 716
Likes: 1
From: Albuquerque New Mexico
I would agree that you don't need anything more fancy than a holley for a street cruiser. Especially a 289 - assuming it's not all radical or anything. I've seen too many negative posts about the demons so even though they look fantastic I wouldn't personally buy one. Maybe if you provided a little more detail on your engine builds people could be better equipped to help you with the selection process.
Le Mans Master
Joined: May 2003
Posts: 8,876
Likes: 3,556
From: Fernandina Beach FL
2023 Restomod of the Year finalist
2020 C3 of the Year Winner - Modified
I've had not one problem w/ my Speed Demon 575 mech w/ electric choke on my C2 327/4 speed. Ran great out of the box-cleaned up my rich idle-and got about 2-3 MPG's more than the previous Holley thenks to the idle ease adjustment(adjustable air inlet at idle). Drove the car on two Hot Rod Power Tours and it preformed FLAWLESS.
OK...I did have ONE problem....When I was selling the car this past summer- I had just cleaned up the engine and accidentily disconnected the choke wire...The buyer was test driving it-ran like crap-no power-felt like it was getting no gas...Pulled over and found the problem. He still bought the car....
Richard
OK...I did have ONE problem....When I was selling the car this past summer- I had just cleaned up the engine and accidentily disconnected the choke wire...The buyer was test driving it-ran like crap-no power-felt like it was getting no gas...Pulled over and found the problem. He still bought the car....
Richard
Burning Brakes
Joined: May 2006
Posts: 893
Likes: 7
From: Hazerswoude-Rijndijk Zuid Holland
While on the subject. What to look for in a new carb? Not looking for a brand or particular model. What specs should a new carb have when I want to buy one for a 1972 454?
Thread Starter
Le Mans Master
Joined: Jun 2008
Posts: 5,284
Likes: 235
From: Rockledge FL
the 454 has the stock cam but 427 heads and long tube headers.
(the 289 on the other hand is built up pretty hot for a ford. its just awaiting carb)
i will probably just go with a street avenger. the only bad things i hear about them are that they need to be upjetted a bit.
id still like to know more about the quickfuel carbs though
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
every carb will need to be tuned to your application regardless of what you buy. Unless you have a custom carb built for your application. The carb i got from Pro Systems was fat 2 jet sizes. Changed them and the car was awesome.
I learned that you jet up or down for MPH, and the squirters and pump shot is for the launch. For a pro street car like i had it took a couple trips to the track to get it sorted out. You can tune out on the highway too to get it in the ballpark, thats the way i used to do it. Have someone stand by the side of the road on the launch to see how much black came out of the tailpipes. Tune one end at a time. Any BBC even a basic 454 should have at least 750-800 cfm minimum.
My Mild 427 that made 450 HP had a 780 vac secondary carb with dual metering blocks. with an electric choke. That carb was perfect for that application once i go it sorted out to what the car wanted .
I learned that you jet up or down for MPH, and the squirters and pump shot is for the launch. For a pro street car like i had it took a couple trips to the track to get it sorted out. You can tune out on the highway too to get it in the ballpark, thats the way i used to do it. Have someone stand by the side of the road on the launch to see how much black came out of the tailpipes. Tune one end at a time. Any BBC even a basic 454 should have at least 750-800 cfm minimum.
My Mild 427 that made 450 HP had a 780 vac secondary carb with dual metering blocks. with an electric choke. That carb was perfect for that application once i go it sorted out to what the car wanted .
Le Mans Master
Joined: Dec 2003
Posts: 5,727
Likes: 38
From: Fremont CA
My expirience with BG carbs is that they have a flaky fuel curve in them and are not on par with Holley carbs. The statemnt being said, I will tell you that I bought a Holley HP+ Ultra 750DP and disassebled it and found brass shavings in the metering blocks by the emulsion jets (I was NOT HAPPY about paying $700+ for a carb with such poor quality standards!) Quick Fuel is a bunch of ex-Holley guys who do a decent job of making their products and I think they do a decent job of building/engineering carbs.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I have a Mighty Demon 850DP on Ol' Red right now. as usual, I bought it and then read all the stuff about shavings. Ripped it apart and it looked better than the new Holley 750DP on the inside- no casting flash, no rough casting, nothing. Took a little more beer than normal to figure out the tuning with the idle air bleed in it, but I got it sorted out and it runs great. No experience with either the Quick Fuel or ProForm.
I was wandering around at Summit racing's showroom in Georgia today and found that the new Holley carbs have holes for idle air drilled in the primary throttle plates. We were doing that 30+ years ago.
I was wandering around at Summit racing's showroom in Georgia today and found that the new Holley carbs have holes for idle air drilled in the primary throttle plates. We were doing that 30+ years ago.
