the secondaries should not open/crack open or anything with movement of the center carb throttle shaft. this will really screw up idle/low rpm run. look for a burr or something were the carb linkage screw rides in the throttle arm slot. jimmy jack Studebaker may have put a screw in there at sometime to get the carbs to open sooner and boogered the slot. those connecting rods should never be tight but have a little up and down movement at closed throttle.

Engine UP to 195

opened center

Front outboard stays closed , rear outboard opens just a hair ( promax baseplate ) I wonder if any relation..

no movement whastosever on outboards with engine running ..
only with Engine OFF

What rear gear? Being that it's a 4 speed, I'd imagine even with 3.55s it would be pretty short and lots of tire spin. I'm guessing it's load related

My 6 pack blows through first so quickly I doubt the vacuum is held long enough to open the secondaries before I shift to 2nd.

If you suck on the pod vacuum hose then close the hose off with your tongue while holding the kill bleed closed with your finger the throttle blade should stay open. If it does and doesn’t bleed down you don’t have a leak.

As a quick test, place a strip of duct tape into the throttle bore and cover the kill bleed hole on both front and rear carbs.

Take it for a ride.

no movement with the engine running is correct.

Maybeee spot on , thats why im wonderin if i should adjust the rev limiter to 7k
But not sure — 354’s now

Itll do wheelies with 4:10’s .. lol

Some interesting reading here

The rest of the story

This

Andy, I can tell that I never liked the Promax Baseplates. While the throttle bores are the correct size it's the blades that aren't shaped correctly. I'll say those bases came and went in popularity. Everybody I know that bought one currently has it on a shelf. The problem with them was... In a drag race you couldn't rely on your carbs to open.


If it were me I would swap the Promax base out with a stock one and I would also measure the size of the kill bleeds. Take off the vacuum pods and shove a wire gauge or get out your 60 to 80 drills and make sure Dr. Drillbigger hasn't been in there working his art. If they are jacked up you just fill them with JB Weld and drill them to the proper size. I would love to find the article that must have been written back in the day instructing six pack owners to drill that passage. Like to see who wrote it... And strangle them


My money is on the baseplate though.

Yep
Nothing like chasing your tail . Youre right

The promax baseplates were a good idea

But these i had milled for me work much better ..

I always Seem to revert back to factory stock engineering

and its most consistent .

, it was an elephant in the room.

seems that folks who get 6paks think that gadgetizing them is the cure for not understanding them or how to tune. I think the most important thing to keep in mind with a 6pak is they are not a race induction system. they are at their best as the premier street and strip induction system. if one needs maximum race performance then use a race intake/carb combo. this isn't to say you can't use a 6pak in a pure race combo but just keep it's limitations in perspective and don't try to make it what it's not.

And these were very discrete and cool
..

Thanks for all the replies
Never hurts to post data to refresh
memory from cars sitting all winter .

Back to factory baseplate

lol .. next post , stay tuned .. how do I get the duct tape out from between the planes of intake ..

I think it would be cool to try. Ive never done that . , it sounds like I can for a day temporarily be John Force after a duct tape mod. .

This all helps to more understand how it all works in unison ..

Tom , or others .. do you swap / have different kill bleed carbs for polyglas racing vs regular fat tire racing ? or rely on springs only ..

The tape trick is temporary. If it works then you know you don’t have a leak but a “combination” issue.

Combination of spring rate, kill bleed size, vacuum, etc.

There are guys running SS 6BBL cars going deep in the 9’s, no apparent issues with the carbs.

I realize the tape is temp .

Glad that you stated that the carbs are used on 9 second cars .
Ive seen and read in other places . But unfortunately
not commonly seen , everyone swears by 4 barrels .
I prefer to do it the hard way .

I guess ill know im good if I can run 10’s on slicks and cruise
On the street reliably .. have to be faster than hellcats .
Tough with a stick ..

The particular quirks with particular carbs are new to me , but tuning the carbs not.
The big cams always complicate it for most .
And an aftermarket or mechanical glitch will drive u nuts .

In response to getting the tape out between the planes of the manifold - make that piece of tape long enough to cover the kill bleed then come up over the air horn of the carb and past the air cleaner gasket flange. The air cleaner lid will hold the tape from being sucked in the engine.

My car in Stock Elimator back in the late 70’s ran 11.50’s in NHRA trim.

9” tire, auto, factory lift hydraulic cam, blueprinted short block and heads using STOCK internals, factory pan, factory intake - race weight was 3725 lbs. on the starting line. I can’t drive it on the street without any problems today.

Using all the stuff available now, cams, more ratio, ported heads with bigger valves, etc. you should have no problem running tens.

Piece of cake.