A few years back I asked for opinions on the 4 barrel carb. of choice for my '84 351W, Holley or Edelbrock. The consensus seemed to be Holley for tune-ability and Edelbrock for ease of use.

Well I am finally near the point of switching to a 4 barrel carb. after swapping the engine to another body, but now there seem to be some more choices, like Summit Street & Strip and Street Demon. Unlike the Edelbrock, they both come standard with the linkage hook-up for my C-6 transmission.

Anyone with experience with either or both of these carbs care to share their opinion? The engine is stock except for shorty headers, dual exhausts, DS-2 ignition and no EGR.

 

I run the Summit carb on my truck and drive it every day of the work week and sometimes on the weekends, 4 seasons of the year and it's great. I've converted mine to manual choke and went down a jet size and changed the secondary spring and accelerator pump nozzle size but that's just tuning it to be as close to perfect as I can make it. I'm super happy with the way mine runs, even out of the box it ran circles over my tuned to death Edelbroke 1406. I also wouldn't hesitate to give that street demon carb a try.

 

That is really good to hear as that is the cheaper option. Anyone tried the Street Demon?

 

The Street Demon is more of a performance/racing carburetor.

For a daily driver, go for the Summit carburetor. I have heard nothing but great things from people running it. And why not? The Summit carburetor is basically an updated Autolite 4100 - the best 4-barrel carburetor ever made.

 

Thanks guys! Any and all insight greatly appreciated.

 

I disagree about the Street Demon. It is a street carb, as its name implies. It has very small primaries and huge secondaries, and is known to give very crisp part-throttle response and good MPG. It is a 21st century carb designed by an ex-Carter engineer to encompass all of the good things from previous carbs, including an adjustable secondary opening rate. And, it is like a Carter/Edelbrock in that it holds gas in with metal (or phenolic on the top-end one), not gaskets. Plus, there's no power valve or diaphragm-style accelerator pump to fail and leak.

I have a 750 CFM Street Demon for Dad's engine, but haven't run it yet. However, Tim Meyer dyno'd an engine with my carb and it came in slightly behind a Holley and close to an Edelbrock. So it isn't a racing carb, although it has Demon-brand cousins that are based on the Holley design and are good for racing.

 

Sorry, I spoke too soon. I saw the word "Demon" and immediately thought of the Holley-style Speed Demon carburetors. I didn't realize the Street Demon was a totally different animal. I don't know *anything* about those, but they do look interesting...a very unique, clean design. I am not a big fan of the Edlelbrock shape, but the Street Demon seems to be a good design.

http://www.hotrod.com/how-to/engine/...on-carburetor/

With the the Summit (and Autolite 4100) carburetor, fuel is *not* held in with gaskets like a Holley carburetor. But you are correct in that they *do* have a power (economizer) valve and a diaphragm-style accelerator pump, like a Holley. But unlike a Holley, the power valve can easily be changed out without taking the whole carburetor apart and spilling gas everywhere. You can also change the jets without draining the fuel and/or removing the carburetor from the engine. Heck, you can even run these carburetors on the vehicle with the top off! Plus, the Summit (and Autolite 4100) has annular discharge boosters (a FORD design ), which atomizes fuel almost as well as fuel injection...much better than the traditional down-leg or straight-leg boosters found on most other carburetors.

The Street Demon "triple stack" booster design looks interesting, but I don't know how it compares to the annular booster design.

 

Gary I would also like more input on the Street Demon design details.

 

I'm not sure what you are looking for, but the Street Demon is like a cross between a Rochester Quadrajet and a Carter AVS, which is basically an Edelbrock Thunder Series. It has the very small primaries and huge secondaries of the QJet, which gives excellent part-throttle response and fuel economy due to the high velocity through the primaries. But, when the pedal goes to the metal the huge secondaries open, and there's plenty of flow for high RPM.

Other elements include the metering rods and accelerator pump of a Rochestor or Carter, and if you pop for the high-end one you get the phenolic bowl design of a Thermoquad and you don't get the hot fuel problems that other carbs give.