750 speed demon i have a 750 speed demon on my 455 mild build and it works perfect,excellent throttle response,looks great and was about 350.00 bucks,great gas mileage too,NOT,doesnt get mileage at all but what did you build your car for mileage or performace,i built mine for performance dont much care about the mileage,if i wanted mileage ill drive one of my other cars,great carbs,was going to go with a 750 holley but guy who built my motor said if you want a better carb than holley go with a demon,thats what i did and it works great.see yah Ray ________ MOTORCYCLE TIRES
I rebuilt the factory carb on my 69 Electra, at 100,000 on the odometer I took it to Flint Mich. and keeping it at a steady 90 mph most of the way back to Milwaukee I got 19.7 m.p.g. The car was getting 8 m.p.g. when I bought it from my dad. All I did was install new rings, bearings, a mild race cam, dual exhaust, ported the intake, and added a spacer. It had 2.75:1 rear end. My new car weighs 2,000 lbs less, will have a bigger engine and I will be running a Holley for power. I remember reading an article about 15 years ago where some guys took a completely stock 455 Stg 1 and bolted on a dominator (w/adaptor plate for the stock intake) and knocked .25 sec off their 1/4 mile time with no other modifications. Buicks just like big carbs.
I've always liked my Quadrajets with Carb Shop innards. Makes them very tuneable. I don't drag race, so I have little 'need' for a Holley. Even in the circle track car, we ran a Quad. No bog, no problem. Plus, I like to hear the bull**** start when I open the hood and hear the slang terms for it. It's usually easy to tell the guys who 'know' from the ones who don't. Still, I'd have to agree with most of the opinions here.
i hate the leaky well plugs in those damn q-jets. i have tried epoxy but that only lasts so long. i don't know what type of epoxy people use but if i do another one i may just dismantle it, let it dry out and just try to solder those damn plugs. i have always had good luck with new holleys. never had much luck with older ones that get rebuilt, possibly bad metering blocks and thats why the newer ones can be had with billet ones.
carbs I'd have to say that i like Holleys also. I have double pumper, mech sec, and the best feature is the annular boosters. It gives a real even spread of fuel into the venturi's. My .02 cents. Gary
Paul, I've been told by our carb guys here at Briggs that they've had very good luck with Hardman Double/Bubble Epoxy extra fast setting variety. -nate
I say to each there own. I love the sound of quadjet being kicked down. But I have had quadjets, holleys, carters, edelbrock, motercrafts. rebuilt them all an ran them all. Thermoquads look cool an are massive in size. But are a pain to rebuild. Damn plastic middle always warps sooner or later. I stick with Edelbrock. I think they are pretty close to perfect for me. Oh an they run real good, hold a great idle, even when you idle them down real low if you wanna. Not much on there squarebore design . I like spreadbores better. Double pumpers- who needs them anyway. I've seen a lot of em jus a puffing away. Every brand carb runs just as good as the man who knows what his moter will take an how to tune it. :beer
What type of carb is the Edelbrock? Is it a Quadrajet type, or Carter AFB type? How large do they make em, CFM wise? Thanks. Regards, John.
The edelbrock is more like a carter afb type carb. 500cfm to 800 cfm in sizes. Maybe higher but I haven't seen one. I prefer a vacuum secondary to manuals. The last one I purchased is a 750 Vacuum with electric choke. It is mounted to a 350 on a truck. Little big I know for a 350, but at time I bought it, I needed it now an the only other option they had in stock was a 600cfm. Oh well it works great. But Heads have been ported an edelbrock emission headers have helped the motor take it reasonably well.
Edelbrock Performer. Passed IM240 test for 1977 emissions, GREAT drivability, and better fuel economy than Holley/Demon carbs. Race Demon 850. Best ET's EVER! Dyno shop with wide band O2, said people would be envious with the A/F ratio results. It'll still start in the winter time without the choke. It's true Buick 455's love BIG carbs! Buick 455 ElectraJim
Just bought a brand new Edelbrock Thunder AVS carb 800 cfm electirc choke for my 455. Hope it runs great.:kodak:
I've had QJ's and Edelbrocks and I gotta say for ease of tuning and reliability,I like the Edelbrock.I've never had a problem with fuel slosh or leakage anywhere.Easy to rebuild and change jets and rods on.Mines just too small for what I have now.Guess I'll get a 750 Edelbrock next.I think alot of it is what youre preference is and what you're comfortable working with when it needs to be done.:3gears:
If you know how to tune a Q-Jet they are a great carb. Back in the 70's a friend of mine and I campained a 68 Camaro (before I found the Buick calling) on the NHRA cuircut. Small block with a q-jet was required for I/SS. We had this thing running high 10's. When I put together my 455 I didn't even consider changing out the q-jet. With a little treeking the thing runs like a scared rabbit. no bog ever and pulls really hard all the way though the rpm range. Wouldn't consider anything else.
Q-jets are good if you want to keep the stock and original look, Hollys look cool and perform like an aftermarket and performance carb should. You didn't see any Q-jets on 427 Vettes or Chevelles, or Z-28 Camaros did you.??? GM used Holleys for max performance!!:laugh:
You might want to read Cliff's post in this thread::laugh: :TU: http://www.v8buick.com/showthread.php?p=1576358#post1576358 BTW, Greg Gessler has gone 10's with a Q-jet. I'm sure that isn't a record though.
13.07 at 104 in my little 350 with a quadrajet that i got off a 69 430 and just rebuilt it! I had a holley q-jet replacement carb on there and it sucked ass.I think with its fumblin and stumblin I ran a 16.5 lol. But honestley I like both tbh.I like Q-jets they look simple and people alllways talk **** to you when you tell them they have one,but the holleys look good to the 850 4150 is a classic performance look,and the dominators look cool when there all dressed up. I reckon for a fully hopped up drag engine a holley seems to be the call but havent some guys ran 10's with a good quadrajet?Im not an expert im just a student with a few ASE's and thats my take on carbs.Take care Russ:beers2: :beers2: :beers2:
