A friend of mine has a dual quad set up he wants to sell me cheap for a 289/ 302 Ford. It has two Edelbrock 1404 500 cfm carbs on it and an offenhauser intake. I'm running an Edelbrock intake and 600 cfm Edelbrock carb right now. My truck run nice but would like to put the dual quads on. Anyone running duals on their vehicles? Pros and cons? Thanks.

 

A single 500cfm is enough to feed a 302 up to 6,000 rpm. Unless you're planning to regularly turn 7,000 rpm, have a big cam, and are running aftermarket heads it doesn't make any practical sense. I'm sure it'd be cool, but it won't run well on a near stock truck.

 

If one 500 cfm carburetor is sufficient for 6,000 rpm, then two of them are good for 12,000 rpm! Sounds pretty sweet!
Of course there might be significant air resistance in the ports at the air velocity required to run the motor at that speed, so maybe it would really have an rpm limit of only 10,000.

 

Thanks guys. I was really planning on throwing 13,000 rpm revs, so the dual quad might be a good idea. I understand the process but am wondering if dual carbs will really hurt my performance? I'm not out racing my truck all the time, but do attend car shows frequently and sure would be nice to pop the hood and see a couple of carbs sitting there. My concern is being overcarburatored. I don't want to spend $$$ on expensive aftermarket heads right now either. My 289 has a mild cam, head have been ported and I'm running headers with flowmasters. So talk me into getting this intake or talk me out! LOL...

 

I'm guessing the dual quad manifold is single plane which typically works better at high rpm when there's plenty of air flowing through the intake. At low rpm - especially if the carbs are progressively linked - the airflow is slow enough you're drawing less fuel/sir into the cylinder than with your current set up. You stand to lose power down low and wouldn't see any improvement below whichever rpm the engine has to turn before it's pulling enough air to open the secondaries.

And...tuning dual carbs is a PITA. Assuming your 600cfm is out of the box, a good tuner could probably wring another 10-20 hp out of your engine. Twice the carbs means twice the tuning and probably thrice the dyno time to get the linkage, rods, jets, and squirters in sync.

Buy it and put it on a shelf until you save enough money for new heads, an XE274 cam, and some 4.56 gears.

 

Thanks Baron, I'm pretty efficient when it comes to tuning carbs, especially the Edelbrocks. Tweaking mine just about everyway is something I can do well now. I'm running 3.50 in the rear now, but definitely need some aftermarket heads. Perhaps I should invest in the heads before putting cash out for a intake and extra carb that I don't need. I think my main reason for the dual quads is the recognition from people when you open the hood. My truck looks great, has a good stance, but definitely needs some Oomph under the hood. A big block would be nice, but I love the SBF's. I'll have to think about this one. He wants $400 for the entire setup including linkage and air cleaner. Hate to spend that on something that might sit on my shelf for a while.

 

If you want some car show attention build yourself an EFI setup for the motor, that will look different and perform better. The dual carb setup will certainly grab attention, but it'll perform awfull on a little V8.

 

^^ X2

Wanna see something REALLY cool? Inglese Ford Small Block Weber Performance
Now THAT will get you the attention you want.


Pete

 

That is a nice setup. I've always love the look of the single webers as well. Let's see, I can get the dual quads, Edelbrock aluminum heads, a cam, and a third member for the rearend, and still have money left over from the price of purchasing this intake / webers. LOL... But they are in the price range of a Supercharger??? These would definitely turn heads a show. Thanks for posting!