Actually intake vacuum drops or decrease as you open the throttle blades then equalizes as the rpms catch up.

Vacuum should be highest at idle out of gear and under deceleration.

That is why I asked what your vacuum is at idle. It should read 18-19" or more. On deceleration I notice it shoots way up over 20" which is normal.

Time to re-connect the hoses and take it for another test drive......

Once corrected then reurving the distributor will make sense.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Well maybe we found the problem,,mine is just the opposite of what you saying Ted..well where do I hook the vacuum line up to..I guess I have to find an opposite source for the vacuum,,man that don't sound right to me. I always though is was the other way around..maybe I have vacuum Dyslexia...LOL.. Now do I have to start all over with the curving?

_________________
Brian Long

Yes, your reading what the vacuum pod should be seeing.
Try the blue capped vacuum fitting under the fuel bowl.
At least the plot points with the vacuum advance plugged in. That column will change.

Hang in there....you will get it dialed in.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

WELL tomorrow's another day..I'll see what happens..I really appreciate your time, and experience. I been scratching my head for weeks-weeks on this thing. hope this gets me up and running right.

Let me see if I'm understanding you correctly..to do the test for the recurve to see what the vacuum readings are, I have to have it plugged in to a full time vacuum source..(blue plug)

To run the car after the recurve is been done and decided, I plug the hose in where I have it now? Or do I relocate the hose to the full time vacuum source (blue plug) and leave it there. Do I leave it where i have it now.

_________________
Brian Long

Yes, the gauge needs full time vacuum for general driving and any testing.
No! Plug your distributor into the ported vacuum fitting.


Yes! leave a vacuum gauge plugged in there. I am hoping that is full time vacuum on your carb. Test it. Like I said it should read over 18" out of gear at idle.
No!

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

ok Ted,,did another run with the vacuum line hooked up to the other port on the carb..check it out..see what you think..I'm not getting 18hg vacuum on that port..somewhere around 12hg.


http://youtu.be/A4kCofAXP5w

_________________
Brian Long

Excellent! now the gauge is working correctly.

That must be a fairly aggressive cam....which one is it?

I still think you need one step stiffer spring on the back barrels.

It is not too far off right now and gets up to speed quick!

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

yeah well,,,it seems to be better..although I put the stock spring back in the secondairies, it still has the cough when you crusie at 60 and nail it,,and even at low speeds as well..say around 20mph and gently give it gas, it coughs. I have the 280/270 erson and I degreed it 3*. It makes alot of power on the bottom,,its real torqueee on bottom,,,with the 3200 stall. The power range on the cam starts around 3000-6000, its fun to drive, and it gets around 18 miles per gallon on premium, as long as I drive it normal..it doesn't like regular,,pings its ass off. It will smoke the 26" tall tire on it, with the 8.75/ 3:23's (peg leg) , It needs a posi in it. I'm looking for one, if you know anybody that has one, let me know.

If you have any other ideas on the bogging problem, let me know. I really would like to get that aggravating cough out..Maybe some Ny-Quill will help..Thanks for all your help.

_________________
Brian Long

Brian,

Map your timing so we can see what is happening. That is next.....for an effective recurve. You need to have a baseline documented.

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Brian,
I gave this thread a quick reread wondering what jetting you are currently using.

Back on page three: Is 52 jetting on primary’s sitll correct?

My cam and setup looks to be very close to yours, except my vacuum readings are not as high as yours, and my in park idle is 1000 to 1100 rpm. Also we are both close to sea level. Recently I installed an o2 sensor to aid carburetor tuning that you can read about here.

Long story short; for some time I have been running stock metering block in secondary circuit, and 57 jets on the primary side in the old Holley 390. This combo produced no stumbles, or flat spots just good response every time the gas peddle moved. I suspected that this set-up was a bit rich as fuel consumption sat around 17 mpg.

With the o2 sensor and gage I was able to see that the mixture was a bit rich. Second jetting test I tried was back to 51 jets that were originally in carburetor when I got the car. The 51 jets caused an instant upset in drivability with flat spots, and bogs galore. Than I installed 54 jets, drivability came back, mixture gage shows lean during light throttle opening, idle, and just into the rich zone during cruse, and WOT. I followed the Holley tec tip to move three jet sizes each time a new jetting was to be tried.

Give 55’s a try, I think you are still a little on the lean side, probably wouldn’t hurt to grab a pair of 58’s while you are at it to save on shipping if shopping on line

Bill

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Yeah Bill
Not sure what the correct jets are..whats the biggest CFM 4 bbl carb that can be used is another question with this setup? I have some bigger jets on hand I can use to see if this makes a difference. I had 54's in the primaries, before I installed the secondary metering block with the 54's, and it seemed to be rich.,,BUT that was before all the distributor recurving started. I had the light springs with the 54's and a softer spring on the secondary vacuum pod. MAYBE if I step the jets up a bit, it may have some improvement. I'll try that next.

_________________
Brian Long

I think CFM wise you are right on with a 390 4V. Some of the guys are running 500 & 600 cfm 4V carbs report good results, but unless you are more racing and less street that is probably too much carburetor for a 225.

One has to consider the air pumping abilities of an engine the size of a 225. It can only move so much air, any excess capacity of a carburetor over that physical limit is not used. Also because of larger throttle plates low to mid rpm air flow through the carburetor is slowed which can compromise response, and drivability.

Here is a web page by a Holley head that may be of interest to you. It is where I got the idea to install an o2 sensor after three years of trial & error tuning, and a bucket full of PV’s, springs, and jets. LOL

_________________
67' Dart GT Convertible; the old Chrysler Corp.
82' LeBaron Convertible; the new Chrysler Corp
07' 300 C AWD; Now by Fiat, the old new Chrysler LLC

Well guys,,,I am still tinkering, and more focused on the carb now, by changing jets, and timing. I put the 58's in the primaries, and it seems to be running rich, putting some black smoke out the tailpipes. Went from 52-58's and jumped back down to 53's. However//when i had the 58's in it the hesitation went away, but felt boggy on the bottom, so I took them out and went to 53's and now the hesitation is back..well I ran out of jets inbetween what may be what I need, could be 55's is what i'm looking for. What do you think about this: I was thinking, I'm using E-3 spark plugs for a stock build, which I am not,,do you think I need a hotter plug for the increased compression (9.7-1) I have now. Maybe this could be the answer?? What do you think I should be running in it, as far as plugs? Maybe my plugs are to cold.

_________________
Brian Long

Brian,

I would order some more jets from Summit so you can fine tune your primaries....

Sounds like your pretty close.

On the plugs I would stick with NGK's. I have had excellent results with them.

Which head are you running? The old style that uses the spark plug tubes? or the new style head that uses tapered seat plugs?

_________________
Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

I"m running the old style with the tubes. What number plug you suggest I run? I'm going to get some jets from summit, and try the 54's through 57. I think the jets are going to do the trick. Now I have a steady timing mark, its not jumping around anymore,,reason being, or maybe not, but I discoverd a mysterious part on the work bench the other day , picked it up, and it was the plastic spacer , I forgot to put on the shaft on top the weights. I done took this distributor apart 10xs already and never noticed it not there, so that coulda been my jumping timing mark problem, maybe it was hanging up .??

_________________
Brian Long