Packard Forum Index » Modification Discussion

Dear All,

Has anyone ever heard of a Packard Six (prewar) being modified by putting on dual carbs? With such a long stroke, low rpm engine does this make any sense?

A dumb idea?

Cheers,

Tom

Quote:

You can't name an engine someone hasn't already hot-rodded many years ago, because it's not always about horsepower. I build obsolete engines and many times it's about the customer wanting something different than a belly-button SBC. Often different costs three times the money for half the horsepower.

It would be relatively easy to make a two, three or four carb intake for the Packard six. Wouldn't make that much more horsepower, but would be an attention-getter at shows. That's the goal for most.

jack vines

Some years ago when I was living in the San Francisco Bay area I saw a '40 or '41 6-cylinder Packard coupe with three carburetors. The hood side panel had to be modified with a hole to accommodate the rear carb and allow the hood on that side to close. Interesting to see, I did not hear it run.

It was displayed at the California Mille show in front of the Fremont Hotel on a lovely Sunday on top of Nob Hill. Ah, memories...

(o{}o)

It is a fairly common thing to do on the early 50's Chevy's with the 216/235 OHV six. Don't know if it helped much, but like you said "cool". Plus you can buy the manifold for the Chevy for not much money.

Edmunds made manifolds, aluminum heads and other accessories for Packard including prewar sixes.

His motto was "Modernize Your Motor". He was not selling to racers or hot rodders, but to ordinary motorists who wanted something extra in performance, without sacrificing the practical qualities.

If you do a search you will find several threads on Edmunds Packard accessories. There is even a brochure or catalog in the photo section.

The consensus appears to be that multiple carbs have been adapted to the six, but the benefit is looks, not performance.

Are there additional modifications to the engine that would increase the performance benefit of multiple carbs?

Thanks,

Tom

Tom, as Stroker McGirt used to say: "The only subsitute for cubic inches is more cubic inches." That said, why not go for a 327 cu. in. 150/180 h.p. engine and an R-11 overdrive? It would be a totally stock Packard drive train and have none of the visible trappings of dual carbs and dual exhaust. This could make you pxxx in your pants. Easy to do and I am sure you guys could figure out how to keep the cane shift with the later trans and od.

I'll try and get the hot rod by the shop tomorrow. I have been there twice, but you were absent.

It's not Global Warming, it's Roadster Weather.

(o{}o)

Roadsta.

As Rusty suggests in post #5 above u'll have to do some research on the multi-carb modification. So Edmunds (or maybe other hotrod equipment companies) may have offered dual carb manifolds but what OTHER parts were also offered/suggested/needed to accomodate the extra carbs.

Perhaps the multi-carb conversions were offered as a package with cam, carb jets and maybe even pistons and heads.

Bottom line, rarely is extra horse power for ANY engine a simple matter of R&R some external engine confetii.

For more power out of ANY engine usualy requires a "street grind" cam change along with some OEM carb jetting and or venturi changes and minor distributor advance changes to the oem distributor. But there in lies the problem: WHAT ARE THE SPECS for a street grind cam????? What did Edmunds et-all offer in a cam?????? At this point noone knows.

Even with all of those questions answered then any extra power obtained will probably be marginal. Maybe only 15% increase in HP at best.

Now if u want to spend months and many thousands of dollars on stroker billet crank shafts, special designed high compression pistons/combustion chamber reshaping, and cam grind experimenting which would require about two dozen cam variations then u can get significant power increase.

Looking for simple sunday after noon bolt on hotrod equipment won't get u much and in some cases NOTHING to less.


Quite ofen we will see "high performance" mods made to engines. Those mods may have been made for any variety of reasons NOT related to performance. I've changed to different carbs on a few engines that were "bigger' carbs but only because i couldn't get the OEM carb and had some misc junk laying around here i could modify slightly just to get the car running.

I think you might get some useful insight into possible performance improvements of dual carburetion on a flathead 6 by chatting with some owners of early to mid 50s Hudson Hornets and Wasps. The standard carburetion on the 308 Hornet was a a single Carter 2-bbl for I think 145 hp. The Twin H option was two single barrels, Carter WA-1s IIRC, with 160(?) hp. Not that you can put a lot of faith in factory hp figures but without doubt the Twin-H was a significantly better performer. How much of the improvement was simple carburetion and how much was enhanced distribution is a good question. Many of those Hudson guys are very performance-oriented and certainly would be a good source of info on dual-carbureted sixes. And I seem to recall that the Twin-H was also offered on the 262, 232 and 202 cubic inch flathead sixes.

The intake manifold is blocked internally between #3 and #4 cylinders so each set of 3 cylinders is isolated from the others except for the vacuum ballast tube that you can see on the far outside of the manifold. In the 7D and 7H versions for 1954 there was also a hotter cam, #311040 if I recall correctly, which gave an alleged hp of about 200. Jack Clifford was the maven of these hot Hornets and offered the cam, higher CR cylinder heads, and a split exhaust manifold which I think was also available on the 7H version. If any of his disciples are around, I'd think they'd be a great source of advice on getting more performance from a flathead Six.

I had some happy times drag racing in stock class years back in a 1954 Hornet Special with Twin H, we had the stock 4-speed Hydramatic reworked by B&M, and also used a DynaPlate dual point ignition system - otherwise stock. On a really good day our best terminal speed in the 1/4 was about 84 mph IIRC.

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