Posted By: rtplumcrazy1
Dual feed 850 Holley vs Six Pack on a 440 - 09/11/11 06:37 AM
How does an 850 dual feed double pumper compare performance wise to a factory six pack set up. Consider that the 850 would have a good aluminum aftermarket intake. The 850's i have had in the past were trouble free and worked great when new. I have also had 2 diff six pack set ups-one worked/ran great, the other one ran so so. Do the 440 six pack carbs flow more air/fuel than the 340 carbs.
Posted By: 340SHORTY
Re: Dual feed 850 Holley vs Six Pack on a 440 - 09/11/11 08:23 AM
I believe the 6 pac will get better mileage when normally driven..
the 6 pac carbs are the same only jetted richer for the 440.
my 340-6 has gotten me better mileage than my 750s that I have ran on it..
Posted By: BIG-MIKE-500 ci
Re: Dual feed 850 Holley vs Six Pack on a 440 - 09/11/11 11:00 AM
One thing most don't realise is 2-barrells & 4-barrells are flowed on a different formula. The six-pac is the equal in flow to 960 cfm 4-barrell.
The main drawback with the six-pac is the manifold. It is quite restrictive so unless you get something like a Hughes Engines Ported one, I'd go with the 4-barrell.
Posted By: AndyF
Re: Dual feed 850 Holley vs Six Pack on a 440 - 09/11/11 05:35 PM
There isn't really an answer for that other than the standard "it depends".
The six pack setup is a great design that works well in certain applications. But once you get outside of its design capability then it doesn't work so great. Same thing with the 850 DP.