Which is better PMO or Weber

[Dpmulvan]

Wondering what’s the better option for a 3.0 build heard both sides of the argument.
Like to hear what those who have used both have to say..

[Henry Schmidt]

Originally Posted by Dpmulvan

Wondering what’s the better option for a 3.0 build heard both sides of the argument.
Like to hear what those who have used both have to say..

Better?
There are many things to consider.
First 40 or 46mm?
New (Spanish) Webers or old originals? At this point I would say avoid the new Webers.
The PMO carburetors are a more modern design and seem to accelerate better. They can be challenging to run if you're trying to run larger header pipes.
For period correct applications, I like the Webers but if you need 46mm, be prepared to step up. They are getting crazy expensive.

[stownsen914]

Of course there is an originality aspect to consider re: Webers. But I've never heard anyone say that Webers perform better than PMOs.

[Jeff Alton]

PMO are difficult to get these days.... Ask me how we know lol... They are suffering some supply chain issues and other issues... Great products, and Richard is a great guy mind you.

Cheers

[lvporschepilot]

PMO are fabulous, no contest. Weber are pot metal things best saved for those going for originality.

[Jeff Alton]

Although we love the PMO product, and Weber that is in proper spec works very well....

Cheers

[Henry Schmidt]

Originally Posted by lvporschepilot

PMO are fabulous, no contest. Weber are pot metal things best saved for those going for originality.

Have you ever tried to run PMO's on a 2.5 with 1 5/8 headers?
Trying the run a short stroke, 2.5 performance engine that transitions well enough for street use with 46 PMO's and larger headers is a struggle. 46 Webers, not so much.
That sounds rather specific but it's not the only configuration that experiences this phenomenon. PMO's tend to prefer smaller headers than some engines would desire.
"Which is better" is always a question of what you're trying to accomplish.

[BURN-BROS]

Weber’s are absolutely fabulous up to a point. Versatile for many displacements. But they do not flow the air like the PMO. PMO can have transitional issues with exhaust size, but ultimately are the only carbs that can yield 110hp/liter.

[lvporschepilot]

Originally Posted by Henry Schmidt

Have you ever tried to run PMO's on a 2.5 with 1 5/8 headers?
Trying the run a short stroke, 2.5 performance engine that transitions well enough for street use with 46 PMO's and larger headers is a struggle. 46 Webers, not so much.
That sounds rather specific but it's not the only configuration that experiences this phenomenon. PMO's tend to prefer smaller headers than some engines would desire.
"Which is better" is always a question of what you're trying to accomplish.

I had a challenging set up recently re PMO transition yeah. Indeed a 2.5L with ge80 cam. So, what fixed it was F2 emulsion tubes with an additional hole drilled at the center of the tube which leaned out transition to its happy place. Took a while to get there, playing with several emulsion tubes, but it’s there

[lvporschepilot]

Adding to this, anyone else notice F16 tubes totally suck with really big cams? F11s F7s won’t work either

[911 SLANT]

I run 46mm PMOs on my 2.8 with Mod S cams , RSR headers and 997 GT3 muffler. Took a few trys with Richards help, but we got the transition dialed in. I run the F16 emulsion tubes.

[lvporschepilot]

Originally Posted by 911 SLANT

I run 46mm PMOs on my 2.8 with Mod S cams , RSR headers and 997 GT3 muffler. Took a few trys with Richards help, but we got the transition dialed in. I run the F16 emulsion tubes.

What was your final setup? By really huge cams, I mean like DC70 and above etc.

[911 SLANT]

38 Venturis
155 Main jets
55 Idle Air Jets
175 Main Air Correctors
110 Idle Air Jets
F16 Emulsion tubes

[911 SLANT]

Still have to get Dyno done to really dial it in. It drives and pulls nice though while I break in motor.