PMOs on a 3.0L
 

Perhaps the brain trust can help.
It’s a 3.0L with Solex cams and about 11:1 compression. MSD ignition system.
AND 46 PMOs supposedly jetted for a 3.0L
It runs very rich and generally fouls the plugs within a few miles
It then becomes undriveable

Anyone have a similar setup, what jets work for you?

What else might be missing in this puzzle?
I believe it is improperly setup, when compared to a similar Weber carb setup as documented in the Performance Oriented tech pages, none of the jets / emulsion tubes / venturis match. Theses are PMOs not Weber’s but you would believe them to be close.

I’m asking for a friend who is at the end of his wits at solving this problem

Thanks in advance

Does the car run well if you can get past the start-up phase?

Was the idle mixture properly adjusted? Are the carbs well sync'd across all 6 throats?

What is the jetting in there now? Hard to say if they are too large or too small...

Is the engine twin plugged? Both sets of plugs working? What plugs are installed? Heat range?

It is typical to go to a slighter hotter plug range with carbs compared to CIS/Motronic.

No, it apparently does run well very long past start up. Accelerates well and supposedly lots of power at high throttle settings but fouls out at more normal driving power settings
Idle mixture set and synchronized across all six throats
Not twin plugged.
Plugs have been changed to higher heat range and tried Iridiums too. I’ll will get the hear range
Jets installed by PMO for this engine setup. I don’t have the numbers. I’ll will get them.
But as I noted, they don’t match Abbott’s jetting chart in his tech pages.

I didn’t state clearly. It does not run very well once past start up especially at lower rpms

79 Row 3.0 heads (large ports)
JE 9.5 Compression Ratio pistons
Solex cams
46 PMOs
36 Venturi
145 Mains
55 Idles
130 Idle Air
190 Airs
F111 Emulsion tubes
SSIs with stock exhaust
Clewett Wires and MSD
Recurved Distributor

I earlier statement about 11:1 compression was incorrect.

I'm running 46mm PMOs
2.8, J&E 9:5.1 pistons, Mod S cams, 40mm ports,RSR headers, 997 GT3 muffler. MSD Ignition, Clewett wires,NGK BPR7ES plugs on Single plug heads
38mm Venturis
155 main jets
175 main airs
55 Idles
110 Idle airs
F16 emulsion tubes
Car runs good, pulls smooth all the way to 6500
Big help from Mr. Parr.

Check fuel pressure, might be to high and the bowls are filling up. Also check the floats and make sure they are closing and adjusted properly.

Yes, float levels are correct and fuel pressure is correct per PMO

It could also be dirty jets. You can pull them and clean them.