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Rolling_Thunder
12-05-2006, 08:01 AM
Well... I am curious... I built the engine in Chris Jacob's GTX.... 440 ci big block mopar with iron heads and a rather mild camshaft.... now my question is... am I loosing power by using a six pack set up ? I figure I am leaving some horsepower on the table by keeping this rather than going to a large 4bbl... but is there anyway to know for sure ?

Shaker455
12-05-2006, 04:05 PM
It depends on many things and you did not go into any details about your engine combo?

Headflow, CR, cam, ign, exhaust? etc

Rolling_Thunder
12-05-2006, 10:52 PM
headflow... good question... ported and polished 906 casting Mopar heads, 9:1 compression, Mopar Performance electronic ignition, TTI headers with 3" pipes to magnaflow mufflers.

Cam specs:
Advertised duration: 300*/308*
Duration at .050: 238*/246*
Lift: 0.480"/0.495"
Lobe separation angle: 110*
RPM range: 1,500-6,500

uses stock mopar rocker arms 1.5:1 rocker ratio

Shaker455
12-06-2006, 02:19 PM
Okay, exactly what carbs are you running and do you have any numbers?

Skip Fix
12-06-2006, 03:30 PM
The reason why tri powers loose some to a GOOD 4 bbl is fuel distribution 6 bbls feeding 8 cylinders. If you have vacuum opening on the end carbs I would think you're in a little better shape. A lot harder to get jetting down at WOT also.

But the WOW factor of multi carbs makes it worth it! And 440(or 340) has to have a 6 Pack! Like a Hemi or a 409 has to have dual quads.

Rolling_Thunder
12-07-2006, 12:19 AM
very true... the guy who tuned the carbs did an excellent job... from park to drive we get a 100RPM drop... cars ? Whatever the factory replacement holleys are for a 440+6 engine.... car made 466hp... keep in mind he was asking for around 450hp so we kept it a mild combo. I was just wondering if there is any way of knowing what kind of power is left on the table short of swapping to a 4bbl...

for another customer I had built a beast of a 440 - made 521hp before with a dual quad set up with 600cfm edelbrocks... swapped to a 1050 on a single plane and cleared 550hp... go figure.

kamaroman68
12-07-2006, 10:07 AM
Chris Jacobs from the tv show overhaulin????

Rolling_Thunder
12-07-2006, 11:30 AM
Chris Jacobs from the tv show overhaulin????


That would be correct

Tech @ BG
01-16-2007, 12:55 PM
Well... I am curious... I built the engine in Chris Jacob's GTX.... 440 ci big block mopar with iron heads and a rather mild camshaft.... now my question is... am I loosing power by using a six pack set up ? I figure I am leaving some horsepower on the table by keeping this rather than going to a large 4bbl... but is there anyway to know for sure ?

Usually the factory setups vs. a good aftermarket single 4bl intake and carburetor the aftermarket setups will be anywhere from 10 to 20 hp better depending on how radical of an engine, setup, tuning, etc. So it's a matter of what you are looking for.