Rod and Custom April 54 article wanted

TerryOH

TerryOH

Well-known member
I would like to get a copy of Barney Novarro article Re: multiple carbs and their modification from April 1954 Rod and Custom. Could someone send me a scan or a copy to trboich@yahoo.com
 
I found a copy...this one is about duals, in particular Strombergs. BN points out that when doubling carbs, the only circuit that actually causes enrichment over a single is the pump circuit. The mod he recommends is to cut pump output 50% by drilling a hole equal in size to metering orifice in power valve through the pump check valve, which is the little ball valve living under the center front plug in carb body. Hole is to go from flange of said valve through its body to below the ball seat. Thassit!
I have no way to scan the article...surely someone on here who is technoliterate has a copy.
 
Is he recomending doing this mod to both carbs? Sure would like to see the article. Thanks Bruce! The check valve is very small.
 
I remember reading that article with check valve in hand...you might need to hire a good Neurosurgeon to get that hole through in the right place! Definitely at least a Starrett pin vise and brand new tiny drill set...I'd probably start with a shallow bigger hole pointed the right way, then start spinning the pin vise and probably swearing a lot.
 
I think there is a reason this has not surfaced in 56 years. Screwing up the check valve seems to me a very bad idea.
If you want less acc. pump you could modify the linkage by lengthing the pump lever.
 
No...bypass is an excellent way to do this. Note that if you can drill as shown, you do not kill the valve, you just allow partial bypass of the pump shot. The alternatives...shortening stroke to less than the Ford range or shrinking the orifice in the jet below pump both would screw up power valve function, either bringing it in too late or reducing its flow and either way leaning out the full throttle mixture.
Note how much stuff in a 97 the pump and the PV share...see the how-it-works bulletins on that!

I think there are some other factors in the problem of adapting to duals...slight leaning of jetting commonly improves things, I would guess because each carb is closer to cylinders and need less compensation for distant cylinders, though major changes from stock are I think misdirections. Duals will also of course have less airflow each and so carbs presumably run into a higher level on the idle and off-idle circuits before venturis come into play...Stromberg was thinking about that too, I believe, with the mods on the last 97's.
 
Your correct, getting a hole as large as .037 past the seat of the check ball would be a trick. about the only way it could be done with any volume is with CNC. Even then I am not sure the hole would not cut through the OD threads of the valve. Beside if you bypass the check valve with a hole, why not just replace the check valve with a orifice with the proper size, since the drilled hole would make the check valve useless anyway, unless the ball in the valve was able to seal the new hole, when it is in one direction as well as the old hole, when it is in the other direction, but that is not how the picture in the article shows the hole.
 
I think that if the drilling doesn't go through the seat, the check should still seal against the backflow except of course what goes through the new hole...I believe the new hole is small enough that there will still be a good push on the valve ball.
There might well be other places a bypass could be placed, if you study the casing... if a good place is found through bowl floor, a hole could be drilled and tapped for a removable jet or plug drilled as desired. Don'y have a Stromberg here in office to scrutinize...
The appeal of Barney's way is that it only affects a cheap and common part, and all is readily accessible to tinker with. Check valves don't really wear out, and you get one with each kit...I might just attack one with the olde pin vise and see if that hole can be accomplished as shown. There sure is more metal in the drawing than in the part!!

Bypass would seem only way to tinker with this circuit, as shared tubes and orifice make it impossible to tinker the squirt side without hurting power enrichment...
 
PS...anyone have the later Navarro article on mods for multiple carbs, I think in an early issue of Popular Hot Rod?? I think that would be circa '62...I think BN ended that article with something like "personally, I'd prefer a late four-barrel..." :)

That later article was from the latter part of the historical period in which people with big displacement OHV engines were putting whole armies of Strombergs on log manifolds...392's frequently got 8! Imagine the pump shot then!
 
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