I am currently running a 3x2 intake setup and want to go with a single 4 barrel. I am looking at the edelbrock performer carb with manual choke. Is this a direct swap onto the original intake manifold. Any kind of modifications I may need to do
I have heard that the Edelbrock carb will run on the lean side at about 3000 rpm I would check more reviews on here before making a decision on this. I ran a Carter AFB and I thought it ran well with this carb but do not know if it would do the same thing at the midrange rpm. If it was me I would get a Holley or a equivalent carb. most do not like the vac secondary carbs so I would run a double pumper. Don't forget you can get this in a 650 cfm. I run a 750 and it works great.
There's also an emissions calibrated 750 Edel carb. It's set up really lean in the midrange. The Edel's will 'run OK'. I happen to like double pumpers and modifying Qjets, as I'm comfortable working with those and I tend to ask for more than what an OOTB offers.
Kind of hard to answer your question without more information. Wasn't there one year Nailhead that got a Q-jet? The rest used a Carter AFB. The Edelbrock carburetors are square bore, like the Carter AFB and Holley. The Q-jet is Spread bore. What carburetor came on your intake?
I feel like I was told that the Nailhead 4-jet manifold has a different square bore from the AFB/Edelbrock pattern. Not sure if this is true but probably worth checking. I got a deal on the Qjet intake manifold from early 66 and the Quadrajet is much better for me than the 4jet. There used to be photos somewhere online of a procedure that cut a 4jet manifold to run a Quadrajet, I think.
Edelbrock will bolt to the stock AFB manifold. That's the setup I'm running. I have a 650, but if I had it to do over again, I'd get a 750. Nailheads like a lot of carburetion. You can rejet or change the metering rods if you're not happy with the mixture.
A Holley 3310 style 750 CFM carb would work great with one of these added; https://www.summitracing.com/parts/qft-63-1/overview/ The stupid spring and diaphragm kits suck, the stupid diaphragm tears every other time the stupid spring is changed!!! The part in the link eliminates that, with a simple turn of a screw for the secondary adjustment. The 3310 Holley on my Nailhead runs great. GL Derek
I guess it all depends what you want to do. If you want to race, Doc has a Holley set up that is pretty impressive. If you want just drive it, then go dead stock. An Edelbrock doesn't give you much unless you know exactly what to do with it. IMHO, it's not a performance enhancing carb, especially not straight out of the box. I've got a refurbished Nailhead Q-Jet manifold and matching carb for sale right now. I wasn't very happy with it, possibly because the Q-jet was sloppily rebuilt. It works, but it needs the touch of a professional Q-jet guy. It does need a new needle and seat, the fuel pump I put on overpowered it and shot gas everywhere. So I took it off and put the original stock AFB and manifold the car originally came with. The point is, the late-67 Q-jet was a far better carb than the original 66 version. So if a Q-jet is what you're looking for, then that would be my choice if I did it over again. The problem is I only have one, and it's currently on the Wildcat. The car is much happier now and so am I. The original carb works beautifully and there are no issues. Sure, it uses a bit more gas and 4 barrel response isn't as raw as with the Q-Jet. But I'm not running races anymore either. Most people that I've talked to have a love-hate relationship with the Edelbrock. It's tuned to run a SBC, whereas the Nailhead needs a lot more carburation at higher RPM. I would try and find an original cast and rebuild it. Or, if you're feeling gutsy and want a challenge, buy the Q-jet manifold and carb from me and give it a shot. But a fair warning, I'm in Canada, and shipping from here is as expensive as shipping from Russia. Comes complete with the proper air-cleaner. It's originally off of a 66 Wildcat 425. It's going to need a kit though. But, there's nothing wrong with the original AFB; - it was a good carb, and it's easy to service. The Rochester 4GC, which fits the same manifold, yeah, that's a bear, and I haven't had too much success in rebuilding them. They have the finickiest float set up going; - you have to be exact and by the book when redoing one of those.
Marc, I hate to admit it, but I use the Edelbrock because I'm lazy. The AFB is just fine, but finding a good one is difficult. The Edelbrock is readily available and is ridiculously easy to adjust/repair/rebuild. IMHO the Holley has too many little gaskets and seals. We used to use them on our oval-track cars due to the side-hung floats, but on a street vehicle I'll stick to the Edelbrocks.
You mentioned the key words; - adjust/repair/rebuild, and you've got a ton of experience with them. And I would agree with you, I've made Edelbrocks work on Nailheads too. A lot of fiddling, but I got one to run just about as well as the AFB did. I must have missed something though, the top end wasn't quite there, but all the same, when there is nothing else, a modified Edelbrock will work. But a half decent AFB off the proper application usually works right out of the box with no screwing around. It's just that a guy would have to know what to do, and there aren't many around who do anymore.
That's the problem with the Eddy carbs is that they run rich from idle to cruise and then go lean at WOT and very challenging to say the least to tune that out. Tuning one gets easier with an air/fuel gauge though. But if you use an A/F gauge on a Holley vs an A/F gauge set Eddy, the Eddy would still hit the trash can with extreme prejudice after experiencing how much better the Holley ran. Derek
Not to hijack the thread, but I priced an #8059 throttle solenoid for my Edelbrock carb today. $165! Does anybody know of a much less expensive alternative? Wow!!
Will this work? Buick dash pot Russ Martin, Centerville auto http://nailheadbuick.com/intake https://lh3.googleusercontent.com/-...4VOHQAq9VwtJwCHM/s640/2004-01-01+00.00.19.jpg
Russ Martin Centerville Calif http://nailheadbuick.com/intake Scroll down to near the bottom of the page $35
there's a cheaper quick fuel version of that also . just not red n pretty . I made up a quickee "tool" for installing the vac sec diaphrams on the holleys - i'll try and find my pics n post a couple . easy enough to make - I used an old dish drainer silverware holder cut down , drilled a few holes , added screws , mounted on a little piece of wood . works fine and keeps the rubber from getting weird as you add spring pressure . the last pic is with spring pressure applied .
Regarding Dashpot (which should be posted elsewhere i guess) Russell Martin sells the GOOD genuine/proper parts, but since NOS supplies are limited there is an Echlin substitute available just in case. About the same price but not all steel or period correct. But Please support your Buick Guru's whenever possible as they do this for the love of the Car!!
