Dual Quads....
 

okay, dual quads are pretty much on the insane side i know but would they really help at all if you just bolted them onto a stock 289?

obviously if your getting dual quads your going to be doing other things to the engine but im just wondering how much having dual quad carbs really helps and what it really does?

RE: Dual Quads....
 

well it would be totly point less a great wast of gass $$$$$[:'(] if the engin dosn't have cams or new pisonts or even a supercarger it would just wast gas.... so u would gain some horses but it would be pointless

RE: Dual Quads....
 

yeah i dont really ever plan to get dual quads on a car of mine but i was just wondering what the point of them was....ive heard too much carberator can lessen power so i was just wondering if dual quads actually would hurt the power more than help the power....

sure looks cool though.... :)


"My 4-speed, dual-quad, posi traction, 409..."

RE: Dual Quads....
 

I have an old 2x4 intake for a 289/302 bolted to my Cougars 289 right now. It doesnt run, but it was a surefire way to keep it from walking off. Just putting it on wont help much, they are a pain to set up and get running right. To run them sucessfully, you need airflow out of the engine, and compression and cam wont hurt either. I might keep it with some small Edelborck carbs just for the WOW OMG factor when I pop the hood, but that car wont get driven alot. The manifold was just lying around and I was leaving for the Air Force.

RE: Dual Quads....
 

I'm not a pro at carbs, but from what i've read, the most carb you'd need for a 289 is 600 cfm (here's a calculator i found online... i'm not sure how reliable it is though http://www.4secondsflat.com/Carb_CFM_Calculator.html )

Too big of carbs will lead to a drop in first, off the line acceleration (torque), and even bigger will drop your horsepower too (not enough vaccum to keep air velocity up)

RE: Dual Quads....
 

there were 2 65 gt350R's that shelby put dual quads on and ran in b production scca, they made about 400hp and to my knowledge were webers and were a pain in the ass to tune. I do know that both carbs must be tuned presisely or it will screw the low end power up[sm=gears.gif]

RE: Dual Quads....
 

For pure wow factor,dual quads can't be beat for that period look on a classic stang.And,if you have enough compression,cam,and headers,you will make power with them.But,its not usually in the power range needed for street use.As far as setup,when properly tuned they are as docile as a single 4 barrel.I think my next project will be a killer 289 with AFR aluminum heads and dual quads.Just my 2 cents. www.1969boss429.com

RE: Dual Quads....
 

Ok, if you look at that calculator, which i have bookmarked it, for awhile now, you will see, that a 289 will 100% air flow efficienty only needs around 450 to 500 CFM. I wouldn't put no more then 500-500 on my 289. Now my chevy 350, will run nice with a 600 CFM carb.

RE: Dual Quads....
 

You can continue to reference the charts and graphs,but,if you want to wake up your 289 go to a 715 cfm carb like Shelby used but be sure to do the other mods as well.The tables and charts were mostly for stock engines.

RE: Dual Quads....
 

Actually, no. I said 100% effiecienty, which is a VERY HEAVILY modified engine. A stock engine has around 83% efficienty and only needs around 380 CFM. So as i said before, 500 CFM would be plenty. Shelby must have really had an overkill carburator on those 289's back then, but they also had a supercharger.