I've got an Edelbrock 4bbl 500cfm but it just doesn't run right. I've been told QJs would be a better fit on my 265. Any thoughts?
If your Edelbrock 500 is an AFB style carburetor, a quadrajet won't fit your intake without an adapter. It would have to be a wild 265 to require more than 500cfm on the street.
Have you tried "tuneing" the EDE ? If not, spend the $ on the "strip kit" from Ede, read the book and tune it, then forget it. Edelbrocks are very easy to tune and veryreliable once adjusted for your combo. QJs are very good carbs, but much more intricate.
I have the edelbrock q jet and wouldn't use anything else.They work great on my hot rods and my 4x4's. Secondaries the size of frisbees are cool.
what GreenMtnBoy said... they don't always work right out of the box, and even when they do, they can be improved. Tune it...
The Edelbrock can be tuned to work right. Qjets work on everyhting because they only open to give you as much air as the motor can use wide open. AFBs are less trouble, my opinion only. Theres is a web site on tuning them, search Edelbrock
If you buy a carb you get a DVD video. It's rather basic, but shows how to change the jets and metering rods. Don't know what you mean by "right" but it could be just a quick adjustment away.
I'm thinking you need to be more specific when you say "it just doesn't run right" what the hell does that mean?
I agree with RatBone, a Q-jet is a damn good fuel mixer. We ran one on a 302 bracket racer for a long time and it always worked well.
I've always loved my edelbrocks.... but i'm not a carb guy so never "tuned" them, just had good luck outta the box.
If you can tune a Q-jet, you can build a spaceship to the moon. Overly complicated, and VERY tempermental. Get the tuning kit for the Edelbrock, and run it. Beats changing the manifiold.
I've got an Offy 360 intake. The motor falls on it's face to the point it will die if you punch it from a stop. Anything above 3K RPMs seems to run fine, but think it could be better. Anything below 3K and it just doesn't go, sluggish. Hot starts are killer, sometimes have to start it WOT. I've thought about tunning it. Eddie has a DVD?, that I didn't know or didn't get it last year when I bought the carb.
you have problems not related to the size and make of your carb. it could be a vapor lock thing, or a vacum leak, a bad accelerater pump in the carb, plugged jets or other things. I would also look at your distributor. you might have timing advance problems or the timing set wrong. if you have vacum advance you need to see that it works and be sure you have it sourced to full vacum at idle for best street ability. its hard to diagnose things over the internet but that should get you started. for what its worth i would favor the qjet on a motor like yours.
The distributer has a Crane XRi. Accelerator pump pumps, I just think the carb isn't set right. Manual choke, doesn't seem to help. Hard cold starts too if it sits.
It also has two connections for vacuum advance (left side and right side at the front), try the other side and see how it works.
Let's see; you're running an Offenhauser 360, which is basically an open pit, on a 265 cubic inch engine that's a little short on torque anyway, and it feels flat below 3000rpm? I think the problem is more what the carburetor's bolted to than the carburetor itself.
I don't know that much about carbs, but I was thinking the same thing. Big single plane and a small engine..... Glad I wasn't the only one thinking it.
This what my offy 360 looks like. No open pit single plane. I plan on running a 500 cfm manual choke edelbrock 1404 with an adapter plate on my 283 bored .040 with a mild "RV" camshaft. I had a qjet on it and bogged down. I think quadrajets are great but maybe a little too big for a 283 or 265.
A Qjet is a great carb, but will usually bog the hell out of a 305 or smaller unless it's in a lightweight car with low gears. The secondary opening rate is adjustable, but when you get to the point they won't bog most little engines on the shift, the 4bbls don't open til 4000 rpm WOT. So I guess my answer is that the Qjet could be a great choice if you've got a fairly agressive rear gear, otherwise stick to your eddy and use the "strip kit" advice mentioned previously. From your description of it's performance, I'd vote for big vacuum leak being the root of your problem. Ever had that 35 year old manifold checked for trueness? Good Luck!
I installed a 4 barrel intake, an Edelbrock 500 and adapter plate on my 264 Nailhead. Ran great outa the box then I tuned as per the instructions and it got better. One of the best starting AND running engines I own. Makes the ol 55 Special step right out when ya hammer the pedal and I'm averaging 12.4 mpg. Go to edelbrock.com and click on "tech support". You can download the installation instructions AND videos of "how to" stuff like tuning and troubleshooting. Absolutley killer and should be exactly what you are looking for right now. Good luck!
With that said above, what intake should I start looking for, that will work with my eddie? I also have a tripple duece intake, but no carbs, I'd really like to go that route, but I don't know anything about doing a tripple deuce set up.
Any aftermarket dual plane intake that will accept a square bore carb like yours will give your 265 more grunt where it needs it.
If you are having problems with a single four you don't need to look at trips. Even a 500 Edelbrock might be too rich for a 265 and you need to look at a manifold similar to the Edelbrock Performer series. Single plane manifolds are more top end (higher RPM) than your 265 likes unless you are racing all the time. Look for a stock Chevy four barrel intake, there are quite few of them still floating around the swapmeets decently priced. I took the Offy and trips off my son's 283 because he was driving between Oklahoma and Colorado Springs. For him the tuning effort was too much trouble so we put an Edelbrock Performer and Edelbrock 1405 (600 CFM) on it at the Summit tech's recommendation and found we had to order the tuning kit and jet down quite a bit to get the best performance out of it. I wish I had bought the 500 CFM model.
Get rid of the open manifold and put a dual plane on it,insure you have 8 initial and about 34 total all in at 2800,Any vacuum ports that are plugged with vacuum hose and a screw must be done right with actual vacuum caps,Insure float level is correct,Make sure when ya bolt up the aluminum intake you DO NOT use the FelPro blue permatorque gaskets! Use Edelbrocks with the RTV oring built into it. Just a few hints....
C/56, What cylinder heads are you running? Stock 265" heads,even power packs have very small intake ports and the size difference in the head/manifold junction will be considerable.The mis-match in sizes will really upset flow.I am running a 283" top on my 265",meaning heads and a stock C.I. 4 bbl. manifold,Rochester 4 jet carb..Runs well and will buzz over 7000 if needed.Yup i'm running hard lifters! Good luck with the 265" glider. My thoughts on carb/manifold? If you have stock heads run an early stock manifold and a wcfb or rochester 4 jet.Small engine/small ports,runners= hi air speed and a happy mini-mouse!
Hi '56, I don't wanna' be a dick (sometimes I just can't help it...) but to make 3 deuces work is going to be harder than dialing in an AFB. Those AFB's (Eddies or originals) are about as simple as it gets. Switching to 6bbls would look cooler, but if you think this is a "learning experience" now... you'd be asking for an advanced course. I'm a fan of 'run whatcha' brung. I'd try tuning the carb you've got on the manifold you've got. Chrysler put a single plane 4bbl set up on their 273's; they drove real nice. Like other guys have said, check timing related issues. Make sure advance (vac & mechanical) is working. I've chased jet/mixture problems, to have 'em go away once I brought out the timing light and got the spark curve right. I have the old Carter strip kit. It's similar to the edelbrock ones, except they had a lot more stuff in one box, instead of smaller 'mini kits' tailored for specific carbs. Here's the eddie page with the kits. If you look at the metering rods, they're marked with the sizes (.068 x .052, etc.) instead of the old (gay-tarded) Carter system of having to look up what size a given part number is. The larger size is the end of the rod that you'll be using at off-idle and part throttle, once you start to get on the main circuit. The smaller size is the 'power tip', which is what will determine your mixture when you're on the throttle, and the vacuum drops off. One question is: what do you do to make the motor bog? Is it whenever you mash the pedal fast - but not if you roll it on slow? Does it bog even if you roll it on, but not until you get the pedal down to the floor a bit? Or does it go soft as soon as you go past 1/4 throttle, but kind of pick up as you step harder, even before you hear the secondaries kick in? Because the way it acts would change where to look to change jetting (assuming the timing is correct and there are no vacuum leaks). If it goes good all the way to the floor as long as I don't tromp on it, I'd try adjusting the accel pump so that it gets the biggest shot. See if it helps or not. It's an iterative process like getting a glasses prescription. You know, "is A better or worse.... A or B, A or B..." Lemme' see 'em again, doc. It takes time. I think it's kinda fun, myself. Don't get pissed if a change makes the car run worse - that's cool. Then you know to go the other way! Just don't get 'tricky' and make 2-3 changes at once and get all confused. Don't ask how I learned that... For weak off-idle that can't really be cured by changing idle mix, I'd try looking at the larger step (aka the 'cruise' portion) of the metering rod. If I were starting with a .065 x .052, then I'd try an .062 x .052. Try changing just one thing at a time - power tip or cruise. Run it a while and see what it does. If it doesn't like what you did, try going the other way. Once you've got the off-idle and part throttle dialed (or if it ain't solving your problem), go for changing the power tip. From .065 x .052, to .065 x .047 or .065 x .037. And you can try changing the springs under the metering rod pistons, too. Stiffer springs bring on the richer 'WOT' calibration, and softer springs roll the extra fuel on more slowly. Notice that I haven't even recommended lifting the lid on the carb yet. All this tuning is done by throwing the air cleaner on the bench, and just turning 2 screws (don't drop 'em in the carb - or get a skinny magnet-on-a-stick if you do) on top of the air horn. To make global changes, unhook the accel pump linkage, and the fuel line (unless you've got several inches of hose that allows you to flop the lid over w/o disconnecting the line) and change the primary jets. That'll change mixture on the primaries from part throttle to WOT. Be sure to use a real good condition screwdriver that fits the jets well. Don't ask how I learned that... If the bog only happens when the secondaries open, then it's time for secondary jets. But I'd still make a run at metering rods to get the primary side close before I changed secondaries - because if it's already a little off on the primaries, and I jet the secondaries in a way that masks it, my mixture still isn't right until all 4 open. Bottom line, remember the jets aren't welded in (although they can be tighter than fuck the first time you pull 'em out) - you can always change 'em in ten minutes if you don't like what they do. Have plenty of coffee or sodas around and enjoy yourself. Once you've got your own car dialed in, you'll be pretty comfortable working on this stuff, and a lot better prepared to handle a 3X2 setup. -bill
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