I have a 355 with flat top pistons, roller rockers, vortec heads and intake, true dual exhaust with custom H pipes and flowmaster mufflers with turn downs. Runs great, however it's running super cold and wants to almost stall on take off. I think it could be the carb but I'm looking for suggestions. Right now I'm running a 650 holley. Any suggestions?

If it will take the gas pedal slowly, then check if your carb's accelerator pumps are working.

what is your fuel pressure? Floats stuck?

FiTech self-learning EFI:

http://fitechefi.com/

GD

Try TUNING the carb.

They're NEVER right if all you do is take it out of the box and just slap it on there.

Welcome aboard thirdgen.org.

Every time I see a "what's the best carb?" question, I kinda chuckle. Because there isn't any answer to that question. Because it's the wrong question. The question should be, "What's the best carb for _____________?"

What's the best carb for a car only used for drag racing? A Holley double pumper of appropriate size.

What's the best carb for street/performance? A factory CC q-jet (bar none - there is no better carb out there, factory or aftermarket, for that use - if your car has one on it now, that is).

What's the best carb for the wallet (non-recurring)? Edelbrock Performer (and that's about the only good thing about that carb).

What's the best carb to replace EFI? None.

What's the best carb to replace your Holley 650? Probably none.

Now, having said all that...

Try that.

There's a sticky thread in the top section of the Carburetor forum that explains how (guess who wrote it...).

Hey Five7kid - what's your objections to the Edelbrock Performer? I'm just curious.

I've used them for basically stock engines and had pretty good luck. Just used one on a family members 56 Buick 322 nailhead. Worked really good. Granted it's stock and has a dynaflow.... I find them much better at running out-of-the-box than the Holly in my experience. They share some design similarities with the Q jet, which I also like (non CCC versions).

GD

They do generally run okay out of the box on mild engines. And can be tuned if you're willing to figure out how. Often used to replace a factory q-jet, which doesn't make a lick of sense to me.

Mostly, though, there are a disproportionate number of threads on the Carburetor forum about problems with them (compared to q-jets and Holleys).

What problems are people normally having? I only ask for my own educational value as someone that maintains a few of these.

It seems like tuning them is fairly similar to a Q-Jet as far as the metering rod system, and similar to most other carbs with regards to idle speed and mixture.

I have referenced this article for adjustment:

http://www.fordmuscle.com/archives/2...ockCarburetor/

I have a wideband we use for tuning EFI but haven't felt a compelling reason to hook it up to the few Performer's I have running. Maybe I will do that next time I have an occasion to tune up my truck and see what the factory settings yielded on it's stock 350.

I rather like the metering rod system vs. the air bleed/emulsion tube system. It's a little easier to wrap my brain around. At least it seems that way to me. I've done a lot of work with Weber carbs on 4 and 6 cylinder engines and they always seem to have more progression issues off-idle that need to be tuned out. I have only minimal experience with Holley's but obviously they are quite popular.

I always liked the metering rod system of the Q-Jet and I really feel that the Q-Jet was the absolute height of carburetor technology - Rochester spent decades and tens if not hundreds of thousands of man-hours designing it. The Performer, at least it part, built on that design.

Could be that I'm not experienced enough with them though. Admittedly I build EFI race cars (mostly Imports) so I haven't as much experience as some here.

GD

Pretty much across the board: stumbling, bogging, running rich, running lean, etc., etc., etc. The Edelbrock instructions aren't bad, actually, but getting people to go through them and figure out what they need to do is like pulling hen's teeth. That's not the carb's fault, though.

The Performer is actually based on the old Carter AFB design, and the q-jet was a move up from it. There have been a few improvements to the Performer over the years, but the basic design is unchanged from the AFB.

Again, it's not so much that they're a bad carb, I just don't think they're the "best" choice in the majority of cases. If you have a factory q-jet on your 3rd gen, there isn't any reason (in my mind) to change it to a Performer. If you have EFI, I'd recommend you keep it rather than switch to carb (regardless of type).

Edelbrock bought design rights for the q-jet from Rochester about 20 years ago and worked with Weber to go through the design and try to improve it. I had a couple of their "updated" q-jets, wasn't particularly impressed with them over the factory Rochester units. And I still think the CC q-jet is superior in every fashion.

FWIW, I see a lot of different carbs out at the track. The vast majority of them are Holley or Holley style. There are some Performers on some of the street type cars, most of them mild (one guy had dual quad Performers on a '65 Impala 327 - the car was a dog). The only racer I know who has had any level of success with a Performer carb is a 15-sec '64 Fairlane with 289 (one of the ugliest cars you'll ever see - even uglier than my Berlinetta), multiple season championships in that thing. He also has a full-on race '64 Fairlane (tube chassis, fiberglass front end, 500+ cubes); guess what it has on it - a Dominator.

I've seen a lot of really messed up q-jets. The one that was on my truck was a Carter, licensed by Rochester unit - had a reman sticker from Holley on it, and I think came from a dodge truck originally. Then the guy before me tried to get it running with two plug wires swapped. I got it running decent but the choke never worked right - I put one of the electric retro-fit chokes on it but it didn't work for poo either. The manifold was butchered and I couldn't get the hot air port to seal up because they chowdered the bolt holes. So I got an Edelbrock carb and manifold used for $280.

I like that they work so well out of the box on stock applications and they are really reliable. All the cruise-in types seem to run them. Don't see them at the track but what we do see now is the carb guys constantly under the hood and the fuel injection (FiTech, Holley, etc) guys just standing around.

GD

There's ALOTTA those in the world.

What that really is/was, is that there was a serious fire in the Rochester plant wherever they were making Q-Jets, and to keep up with production, they hired Carter to make them for them. Not sure if it was just the castings or complete assembly or what. But for several years at least, all Q-Jets had that on them. Also not sure whether GM ever rebuilt that plant and resumed production, or, seeing the end of the carb days approaching, just left the "temporary" deal in place until the end.

Yeah I know what you mean about the carb vs FI situation... The really serious knowledgeable type guys are pretty much all swapping over to FI, slowly but surely. But the "old skool" "I hate all that electronic crap" "Ima yank out all those wires so it looks good" types, who basically are like that in the first place because they don't have 2 technically-inclined neurons they can rub together and get to fire at the same time, can't keep their stuff working right anyway, no matter what it is. Not least because they mostly just don't know what they're doing.

I'm glad that I am not the only one. A properly adjusted ThermoQuad (not plain AFB) might be in second place, but it is a definite second.