six pack set up

[72rtchallenger]

Is a progressive linkage better than vacuum or  vacuum better,,any problems with a progressive that I am unaware as that is what I use,and so far like but have never used the vacuum 

[426HEMI]

The progressive is more responsive to me  I have used both   

[dodge freak 2]

I run dual carters and tried both ways..either way seems good. The 1 to 1 linkage gives a bit more power at tip in but running progressive it can take off just as quick just have to push down the go pedal a bit more.

I have a manual valve body on a "auto" trans and running progressive allows for softer shifts at part throttle so that is how I run it now.

Once the secondaries are tuned right--light springs or in my case lighting up the secondary weights--the secondaries kick in quick and seamless.

Not sure how a "6 pack" would be, with dual quads I get 4 little primary barrels any time I floor it, with 4 more secondary barrels ready to come on as needed but part throttle I have just two little barrels going.

Mopar should have put an "8 pack" on those cars IMO   

[Chryco Psycho]

I prefer the non vacuum system

[Changin Gears]

You can get by with the vacuum setup with an automatic, but with a stick you really want the linkage (unless you power shift all the time).

[Oldschool]

Progressive for me....      

[Roppa440]

I have a progressive manual linkage on my six pack with accelerator pumps on the outboards.

I fitted a 3" tall air filter that would flow more than enough for the carbs as the stock filter is too restrictive.

But! At WOT is my six pack now "too big" for my engine?

I fitted a MAP sensor to the intake to measure manifold vacuum and record it on my LM-1 meter (along with RPM and fuel mixture). On the track at WOT I am getting a reading of ZERO manifold vacuum.

I know that if I had like 2 inches of vacuum at WOT the carbs would probably be too small. But how to tell if they are really a bit too big?

I was thinking of backing off the opening of the outer carbs a little to a point where I JUST start seeing some manifold vacuum.
Do you think that is a good idea?

[Roppa440]

Ooops!

Forget everything I just said.

I messed up on the software. In fact i have 1.5 inches of vacuum at WOT. So that is probably perfect.

I was just being dumb as usual.

[moper]

I like the vacuum on anything but a full on drag car.

[340_6pak]

I fitted a MAP sensor to the intake to measure manifold vacuum and record it on my LM-1 meter (along with RPM and fuel mixture). On the track at WOT I am getting a reading of ZERO manifold vacuum.

Roppa440, where did you get that sensor? It looks like a cool addon.

[Strawdawg]

Roppa440, where did you get that sensor? It looks like a cool addon.

You can get one at your local parts store in most cases.  They are used on fuel injected cars.  A common one is used on the turbo Buicks....say an '86 Regal with the vin 7 turbo engine.  Those require a 5.0 volt power wire and a ground wire plus a connection to manifold vacuum.  The signal output will be between 0.0 volts and  ~1.6 v for vacuum.  This is for the three bar turbo Buick sensor at sea level.  1.6 v would be zero vacuum.

There are other "bar" versions and the voltage scale will be different for each version.  A google search should turn up the voltage vs vacuum/pressure for each.

I think the one bar Chrysler maps put out abou 4.5 volts at 0 vacuum and something like 0.2 v at 15" of vacuum. 

[Roppa440]

I think mine came off a GM truck. Sorry.

I made the 5v power supply myself and mounted it near the dash gauges just in case the originol one for the fuel gauge ever stops working.

You can make a power supply for a couple of dollars.