Packard Forum Index » Modification Discussion

Hello ,I was wondering if perusing a dual 2bbl intake would make much difference to a stock 327 if the cam is a stock one? It would look cool .i heard there is better mixture flow than the one 4bbl .Thats the first " mod"did andI was happy with a 53 intake and ,and 4 bbl intake conversion of the 52 2bbl original , I saw some folks that have edmunds 2 2bbl intakes for sale I still have my original 2bbl carb in the garage

It sounds like that might more power improvement than perusing the illusive aluminum head

Has anyone ever tried making a custom dual 2 barrel intake manifold? TIG welding some aluminum tubing to make a custom manifold shouldn't be too hard. I know the hot rod guys do that a lot, and it would probably be less expensive than trying to find an old Edmonds manifold.

Other than the "cool and different" factor, the 2x2bbls would be no real performance benefit over the single 4bbl.

jack vines

My thought was that the dual 2 barrels would even out the fuel distribution more than one center mounted four barrel. Maybe wrong there, as I never studied air flow dynamics etc.

David, I think you may be on to something.

If you have noticed, the new thing for hot rodders is the dual and four pattern cams. These cams are designed to optimize valve events based on intake runner length, due to the conventional V8 intake center carb layout. These new cams compensate for the different runner lengths by phasing the opening and closing of the outermost cylinders thereby increasing both torque and horsepower across the rpm spectrum. NASCAR has been utilizing this for years.

A dual carb manifold on a straight eight should definitely help. Even better would be to have a custom grind using this four pattern technology. I would think that if we consulted Comp Cams they would be able to engineer it.

It is a much simpler solution than variable cam timing, and with less moving parts. Should be an easy mod for the Packard eight!

Quote:
Yes, no, maybe.

Yes, that's why all modern engines have one injector per cylinder; sometimes actually in the cylinder. That insures perfectly even distribution.

No, at the lazy RPMs the Packard eights turn, fuel distribution is not really a critical issue.

Maybe, define your goals:

1. Just want an interesting project?
2. Just want some bling under the hood at a show?
3. Want the highest horsepower possible from the I8? If so, why stop at two carbs; go all the way to one injector per intake port.

BTW, joey is just trying to stir up trouble. The dyno time necessary to measure the varying intake flow and develope a computer program to calculate the ideal custom cam timing for each cylinder is a hundred-thousand dollar project.

jack vines

More carbs alone will do no good without other modifications like hot cam, exhaust headers etc. The engine works as a total package, extra carbs are something the stock engine can't use.

Rusty, I agree, an extra carburetor that is the same size as the original one would be too much for a stock engine. However, two carburetors of smaller size could provide better performance than a single large one. It all depends upon the size, jetting, and set-up of the carburetors. Just slapping on an extra carburetor would result in poor low speed performance.

(o{}o)

Jack Vines advice in post #6 above is sound realistic reasoning and applies to nearly all engines of the streight 8 era. JV's post pretty much says it all.

Touchy subject this one. Ill this depends on how far you want to go. The early 4bbl carbs are in the area of 300cfm a new Stromburg carb (the 3 bolt 97 reproduction ones)are according to the Stromburg site 165cfm so 165+165=330cfm so it would only be 30cfm more flow over the stock style 4bbl carb not enough to really feel in the seat of the pants (not saying bigger is always better). With a custom aluminum intake you will be shedding a decent amount of weight off the engine the cast iron intake is quite heavy that will help slightly with acceleration but again would you be able to tell? probably not. With modifying the L8 Packard engines you have to go back to basics in your tactics. Custom grind cam port work 288 head swap (for higher compression) 288 rods (longer so better rod stroke ratio doesn't help much at the RPM these things run at but anything helps)pistons to match the longer rod electronic ignition a well thought out intake setup and good breathing exhaust. If you can compare a Ford V8 flathead to the Packard look at the power gains they get with similar tricks. 80-100hp stock on a V8 Ford to 230-250ish with a decently hot one. If memory serves the 327 Packard puts out around 180hp so 200hp would be easily attainable possibly more if you spend time tuning it in. If you are going for max performance its going to cost if you just want something unique for the car show you can do anything you want.