weber DGEV 32/36 bogging with secondary openning

gearhead138

Active member
I put a weber 32/36 on my 63 Falcon w/ 144ci 6 years ago and it runs great but whenever I open the secondary it bogs down terribly. I've always just used the primary and it runs fine. This carb was origianally jetted for an MG midget. This year I started fooling with the jets to solve this problem. I upped the mains to 160's, primary idle up to 50 ( still to small) and the air corrections are 180 I believe. Still runs great but plug actually show a very lean mix, and still bogs big time with secondary. I know the idle jet is too lean because i'm at 2 1/2 turns on the mixture screw and I guess the air corrections are to big because now I have a lean mix that I didn't have before I started messing with it. The only thing I can figure is the custom intake adapter I built, it's about 6in. tall and tapers from the weber pattern down to the dinky stock intake port. This must be creating some mysterious forces that cause it to bog down. I have never tried any other adapters but I guess that is were I should go next. The carb was new when installed and has run consistently the same ever since. Any advice :?:
 
Sounds like the carb is too big for your engines needs, at least when you open up the secondary. Can you delay the secondary, with a cam, from opening, say open at 70% the primary instead of 60%.
Just my thoughts,
Ken
 
I'll check it out. It will still do 70+ on the freeway but when I try to get that extra bit of throttle it's bogging. It's never been a real factor until I am trying pull hard on a hill or merge to the freeway.
 
It just sounds like the engine is getting too much air and fuel at one time. Can you ease into the secondary side of the carb, does that make any difference?
 
Gearhead138,
According to The Ford Falcon Six Cylinder Performance Handbook, the 144 had a 1.00" venturi 1 7/16" throttle bore for 130cfm. I think the carb you have can achieve near 300cfm. If you want a progressive 2bbl, And who doesn't, I would look for a Holley/Weber 5200 off a 78 Ford 2300cc engine. The primary is 23mm and the secondary is 27mm and can achieve a 235cfm. These carbs are found on Pinto's, Mustang II's, Vega's. I hope this helps.
Good luck,
Ken
 
Has anyone else had this problem with this carb on a 144? The carb was for a 1275cc MG, I guess they must breathe alot better than a 144. I would like to try a 200 head on it, I know that would flow better. I will have to do some machining to get the CR back up.
 
The MG is rated at about the same horsepower than a 144, so yeah it breathes better.

The 200 head will help, but it is an incremental improvement. There just isn't enough displacement to do much with the log head's crappy flow characteristics. To make horsepower with the 144, you'll have to turn some RPMs. It's the only way.

I agree that the 5200 carb will be a better match.
 
This carb is NOT too big for this engine. There are plenty of 900 cc minis and fiat 600 with the same carb, not to mention sprites and midgets. You have a jetting problem.

The bogging on secondary opening is the most common problem with this carb and is due to not having a large enough main jet on the secondary circuit. I cannot recommend specific jets, but I would say that you should go up two jet sizes on your secondary main to begin with, and two more if that is not enough. Beyond that, refer to the sticky on jetting webers and see what jets others are using.

Some tips:
Bog off the line = idle jet too small
Bog on secondary opening = secondary main too small (& maybe primary main too small also?)
Air jets only affect high rpm function = if you get pinging or surging at high revs use smaller air jet.
 
My original post says what jets I am running now, they are much bigger than original and the bogging has always been there.
 
Here is another thought:
d= displacement (d x 2) - 15% = CFM
(144 x 2) - 15% = cfm
(288 x .15) = (288 - 43) = 244cfm
Ken
 
I don't think the carb is to big either, I just need to figure out why it's not breathing well. I have a clifford adaptor but it fits the 200 head so I have been using a custom intake that I believe might be causing a problem with the airflow.
 
Maybe now I understand the problem, and that is you are proving that a funnel will only allow so much product, air, gas, water or oil through it. The adapter is part of the problem. Your carb has a 32mm opening and a 36mm opening, and your manifold has a 25.4mm opening. It can only flow so much, and I think your 32mm is about it.
Even if you do a direct mount carb to manifold, I truly do not think your 144 will utilize that carburetor to it's potential. Unless you are spinning the engine in the 7000 to 8000 rpm range. But hey, that's just me!
Ken
 
I'm still running a stock distributor and I need to upgrade. I'm not losing power at high revs, I't just bogs when I introduce the secondary. I disconnected the secondary and it didn't bog.
 
gearhead138":aejdrt18 said:
I'm still running a stock distributor and I need to upgrade. I'm not losing power at high revs, I't just bogs when I introduce the secondary. I disconnected the secondary and it didn't bog.
Using a Load-O-Matic distributor without a Spark Control Valve on the carb (which a DGV won't have) means your spark advance isn't anywhere near it needs/wants to be.

Other than that, I'd think it's a jetting issue. We know that a stock 144 won't use all the cfm (adapter or not), but if jetted right it should work.
If not jetting, I'd look at the secondary fuel passages, make sure the secondary can/is moving fuel.

Do you know anybody with a wideband oxygen sensor / gauge? I found them to be extremely helpful in jetting my H/W 5200.
 
I want to affirm what jamyers said about an O2 sensor - I have yet to spring for a wide band O2 sensor (when I finally bite the bullet it will be for one that includes multi-channel data logging).

I have installed a narrow band 3-wire (heated) O2 sensor in both of my carb'ed vehicles ('61 Falcon w/ Autolite 1100 (DVG withing a few weeks) & '71 Triumph w/ triple DCOEs (3 duces)) for carb tuning. I tried to solve a *rich* bogging issue at part throttle in my Triumph for a couple of years until I added an O2 bung to the header collector and found out that I had a ***LEAN*** issue while transitioning between the idle jets and the mains.

One can do an amazing ammount of carb tuning even with a narrow band sensor (and a narrow band sensor only costs about $25 with another $35 for the gage). Actually I have never bought an O2 sensor for one of my carb'ed cars - I just reuse a high mileage one that I replaced in one of the newer cars! With a narrow band sensor the display will dance arround a lot so I do (visual) averaging to determine if things are rich or lean. With a lightly traveled road, you can play around with the RPMs to monitor what is happening (rich/lean) at a given engine speed.
 
DuraSpark with DSI cap if you want to keep your old plug wires, DSII cap and adapter if you want the newer style wires.
 
I'm not sure a newer dizzy will fit a '63 engine without some modding. iirc, you'll need to replace the oil pump driveshaft, and maybe reduce the diameter of the dizzy housing where it goes into the block.
 
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