(2)450 DP's vs (2)750 DP's

[MomsDuster]

Here's what i'm planning, I have my 71 Duster, 440 Dodge, 10.0 CR, Stealth as cast aluminum heads. 231/237 @ .050 110 lobe separation 106 ICL, Weiand 1987 Hi-Ram Tunnel Ram w/2 ProForm 750 DP, 3000 stall and 3.23 gears. I picked up a pair of Quick fuel HR 450 double pumper carbs. ( https://www.holley.com/products/discontinued_product/parts/HR-450 ) I'm going to swap them for the 750's to see the difference in performance. I'm curious if the smaller venturi's will have better low end velocity and give better low end performance. What does the FABO brain trust think?

 

[Newbomb Turk]

You’ll lose power.

A better option (IMO) would be to call Lightning Racing Carbs and order boosters from him.

Swapping to good booster will do way more for drivability, fuel distribution and the engines ability to RPM.

A smaller carb just kills power.

 

[rumblefish360]

I was always told the twin 450’s for milder street applications.
I’ve road in. 440 Charger with twin tunnel ram 450. I thought it was pretty darn good.

Likewise, twin 750’s for racing, unless it’s a super beast. Back then, a good 30 years ago, I couldn’t understand how a regular 440 could be happy with 1500 cfm worth of carb. It’s a good bit to fully make use of. But I didn’t know anything of this arena and of performance.

 

[66Valiant528]

I've got twin 450s on my 440. Ran the same mph as my 750 mighty demon on an M1 open plenum. 114 mph 3880 weight for my 68 Roadrunner

 

[RustyRatRod]

You HAVE the 450s, so try um. You may lose some all out power, but the response might be better too. Only one way to find out.