g_ride

Im looking for some opinions on comperably flow rated and priced carbs, such as holley street avengers VS. Speed Demon's VS. Edlebrock performer VS. Any other carbs that are comperable(in the same price range, flow rating, and size)

The basis for comparison is cost, fuel efficiancy, tunability, and power increases, on say a mostly stock 350.

If anyone has an opinion on any of these things please feel free to post it (and if its backed up by some fact all the better)

Im asking for two reasons, one, because Im going to buy a new car, and second, because for my second year automotive project we need to do a comparison report, and Im looking for some feedback.

ANY HELP WOULD BE GREATLY APPRECIATED! So please if you gotta moment and opinion, reply! Thank you very much for your time and responses.

five7kid

iTrader: (14)

This is your chance to make your name in the automotive world.

Buy this new car, an A/F gauge, and a weather station. Buy a Speed Demon, Street Avenger, Performer, and Performer q-jet, all 750 CFM. Take the car out to the track, mount the q-jet, get the A/F tuned properly, make at least 2 runs after the tuning, noting the air density for each run. Then do the same for the Performer, Avenger, & Demon. Adjust the data for the ADR.

When you're all done, post the results here, write your report, and get an A for the project. Enjoy your 15 minutes of fame.

The magazines will never do it because they don't want to embarrass any of their advertisers.

g_ride

brilliant plan and all, but time constraints really limit my ability to go out and make enough money to do that. (I'd suggest common sense is a factor, but I dont have much of that so its null and void.)


Really all I wanted was an opinion on any given four barrel aftermarket carb. This does not require any level of objectivity or accuracy, just some base level of information.

Regardless, the deadline is today, and Im currently cutting class to finish my damn report - speaking of which its high time to take off.

88IROC350TPI

Heres how I see it...

Edelcrap: good out of the box for those who aren't much into tuning. You can bolt it down and drive off. I personally dont like them and would never run one but they can be pretty reliable easy carbs. (note: I'm not saying an Edelbrock is an idiots carb, some of you guys swear by them so whatever floats your boat)

Holley: A Holley is a Holley ...a proven performer. You probably wont be able to bolt 'er down and go like an Edelbrock. Probably have to do some tuning to get it feeling just right but the end result is well worth it.

Demon: Same cocept as a Holley, uses the same basic parts but is pretty much all together a different carb. I bet 90% of Demon haters hate them because they tried tuning them thinking they were fancy Holleys. In the end, I think Demons are the best. However, they are a little funny to get perfect ("overly sensitive" I guess would be the word)

Now for gas milage, tunability, and performance? I don't know, it all depends on your combination, driving style, and overall purpose. Personally I'll put a Demon or Holley on anything one will bolt onto.

twistydick

all im gonna say is dont overlook the quadrajet.for the street, if you can tune one, you cant beat the mileage or performance.ive even used quads on mopars.had a 12 second duster that got 16 mpg with a quad.holleys are great too .easier to tune, way easier.but as 88iroc said, it all depends on your purpose and driving style, etc.

MrDude_1

edelbrock... a mix of performance and street... easy to tune, and you can bolt it on and go... but it cant be tweeked to the same degree as the holley. i like them for street cars that get driven alot.

holley. holley makes more then one carb... but in general, they can be tuned to a higher level, and make more power, but they also get less fuel economy then the edelbrock.... but this is the general statement. with the wide range offered along with aftermarket parts, anything is possible.

quadrajet... GMs carb... the front two throttle valves are really small.. so when you're at part throttle around town, it sips gas... but when you floor it, the huge rear butterflys open and it flows really well. problem is tuning.... the large transision between small front and huge rear means that if it isnt tuned right, it bogs for a second... hence the nickname "quadrabog" and why they have a bad rap in the aftermarket.

demon... holly STYLE carb that takes care of some of its shortcomings.... overall, it can be considered a upgraded better carb.. but it shares alot with the holley too... think of it as the LT1 compared to the SBC.... look similar, do the same thing, share some parts, but other things are diffrent. each can be modded to be faster then the other.



thats it in a nutshell.

ljnowell

I think that most people are swayed by personal experience. I have seen nothing but problems out of many holleys and all good experiences with edelbrock. That's why I buy edelbrock and not Holley. I know a lot of people that say the exact opposite thing. NO one is right and no one is wrong. I would recommend an edelbrock, but man, there are a lot of carbs out there. It looks like you've already pinpointed your decision factors. I think that an edelbrock fits the bill for all of them except maybe tunability. BUT, you can tune an edelbrock too, and its not too hard. Go with the gut feeling man, and dont look back.

88Camaro350

I have a street avenger 670cfm. Decent carb but not worth the money over the regular holleys. I am getting ready to get a 650 or 700cfm Holley DP soon. I want mechanical secondaries and choke. If your building a mild street engine a regular holley 600cfm is probably fine. Just depends on what your doing.

g_ride

actually post my little bit of reserch today I was thinking that most likely I would end up with one of thems fancy demon units. The edelbrock seems as though it would be easy to set up, but strikes me as an evolution on the quadrajet, and not really a, " performance carb" or rather not as much as a holley or demon.

In end the findings of my report was that of a road demon, performer, and street avenger, the avenger was the best buy really, I think it's more specific on what you want it to do, so it was a pretty bad topic to choose... *shrugs* oh well. Lets just hope my instructor doesnt pick up on that.

midlifeman

I started out with a Q Jet on mine, it was bad, so after rebuilding the engine they put a rebuilt Q Jet on, which also turned out bad. But that's not uncommon from what I've heard from where the carb was rebuilt at. So the shop I was using stuck a Holley on. It ran pretty good for a couple of days, then started running crappy, took it back had it retuned (I'm a carb newbe so it's not something I knew how to do) and it ran pretty good for about a week. So I took it to a specialty high performance shop and they had it running great, for about 2 weeks. This winter, I pulled the Holley and replaced it with a Edelbrock 1406. Started on the third crank (that was after changing all the fuel lines too) and the car has never had more power or run better. I'm not brand loyal because I'm quite new at this, but that was my experience.

EvilCartman

iTrader: (1)

When I had the 305 still in my car, I went from the stock Q-jet to Holley 670 Street Avenger to my current Speed Demon 750. Out of all those, the Demon has been the best performer. Never checked mileage with the other 2 carbs but with the 750, I got 22 mpg highway going 60-65. That was with my current transmission too which had my RPM's up around 3,000.

ljnowell

I dont think i would call a edelbrock an evolutionized rochester. The performer carb is actually built off of the Carter AFB, which is a good carb too.

MrDude_1

yeap.. its just a carter clone... and if im not mistaken, its cast and made by weber....

weber makes good carbs too... just not for our cars.. i have a weber DGV on my triumph spitfire... i love it.

Stekman

Yes Edel. carbs are carter clones and their bodies are cast off Weber. The "W" Stamp can be seen on the side.

The best balance of the variables you listed would point at a Holley.

MrDude_1

that i listed?

funny... cause i love edelbrocks (carters) for the street... (and for dual quad manifolds)


i only like holleys on street/strip and race motors.



but im ditching all thoes for EFI anyway. :lala:

racindaelky78

i use holley's religiously i make my own basically modify them alot, presently i am running a 650 body,750 baseplate and 750 metering blocks and bowls,and the air horn is milled off. I will get a demon just because they are alot nicer and they flow better and are built with better Quality then a holley.
i dont recommend using a edelcrock, we used one on a 85 Z with a 383 and it took us over 10 hours to get that carb tuned in and it didnt last long staying tuned,besides youve got to buy new needle and spring kit to tune it.

Stekman

That the original poster had listed.

ljnowell

Man, Ive never heard of it taking 10 hours to tune an edelbrock, maybe you got a factory f***up? IT does happen, after all my camaro came with a 2.8, that had to be a mistake!

MrDude_1

not as big of a mistake as the 3500+lb iron duke 4cyl thirdgens.

ljnowell

Isnt that the truth, I look at it like this, by changing my engine I am simply correcting what the General did wrong. Just fixing a mistake.

racindaelky78

just tuning it in was the hard part we got the old 350 out of it and the new 383 in it within 2 hours the rest of the night till sun-up was tuning that carb,it was a severe pain in the ****,it could have been a factory fawkup but i could ahve tuned a holley on that motor in under 20 minutes.

ljnowell

no way can anyone tune a holley to perfection in 20 mins.

MrDude_1

i donno about you, but it takes my car about 10mins just to warm up.

so if you change one thing, you'll have to wait another 5mins to get back up to temp before you can even see your change... thats 15mins right there, not even counting the time it takes to drain the bowls and change whatever you're changing.

GoSlash27

My (admittedly somewhat extreme) take:
If the car is ever gonna be on the street, even just to drive to the track, it should have a quadrajet on it.
-It can do anything the others can do except run alcohol.
-It gets better mileage and better throttle response.
-How else are you gonna run a 900+ CFM carb on a street car? (more top end power)
-It's also the most cost-effective because either your car came with one or else you can get one cheap at the junkyard.
-If you're handy at all you can get 'em for free from your misguided friends who pull off their quadrajet looking for more power. I've got a dozen of them in the garage.
-You don't have to adapt stuff to make it work because your car was designed to run it.

Of course all of this depends on your ability to make it work. Or at least your willingness to learn and experiment.
Holleys are good performance carbs and AFBs are very reliable, but neither one does the job like a Q-jet.

yamahaguy91

i have always heard that a q-jet are really the best carbs . that is if you know what your doing to them. but for me iam more of a eld. man just like the looks of the carb better.

ljnowell

Amen to that. The edelbrock does look pretty under a hood. Not only that, they run better too. Thats the only similarity i see between Qjets and Edelbrock. They both have extremely nice street manners.