The moral imperative of the Solex 40 P1 fraternity

[kenikh]

I'm going to stand on a soapbox for a moment, so indulge me if you please.

The Solex fraternity is a tiny collection of folks trying to "do it right" with these cars. Although a small group, it is growing. It is also becoming increasingly prohibitive to put a Solex car back right. I'll attest first hand, having just completed the effort myself. Refitting Solexes to one of these cars is an exercise in the irrational, where someone starting from scratch will likely exceed $10K in expenditures going from Webers to Solexes. The "new normal":

• ~$3500 to buy crusty and hopefully complete cores
• ~$3000 to rebuild those crusty cores - ball and pintle accelerator pumps can take weeks to unseize and repair
• ~$2500 in labor to install. Reinstalling these carbs was above my skill level, so I had an expert take a crack. My fully rebuilt Solexes had enough teething issues, that this is what it cost me at the "friend's" bill rate.
• ~$1000 in ancillary things like a fuel pump, linkages, fuel pipes, fuel pump rebuilding, etc.
• ~$500-$2000 for a complete airbox on Ebay (WTF?!?)

Now that I am done with my reinstall, here's my plea: as a community, please lend a helping hand to those committed to "doing it right". I'm walking the walk - I recently sold one of our fraternity (pretty much gave him ) my only two NOS Solex float bowls in the pursuit of getting his car back on the road. What would they have brought in on Ebay? Who knows, but NOS and Solex 40 P1 these days means all bets are off. But they were given to me years ago in kindness, and I've chosen to pay that kindness forward.

My plea to the community: if you've finished your project, put fraternity ahead of profit where you can. Some things you need to keep for the future, other things you don't. Help where you can.

Thanks for considering.

[E911]

Ahmen.....

[Per Schroeder]

Very cool. Did you document any of the issues online? That often helps get the ball rolling. I remember looking up a lot of MFI stuff when I had my 69E. Even the most basic primer site can really help.

[kenikh]

prices will only go up as more 64-66 get restored and put the webers back to solex as so many solex's were discarded. Supply and demand.Applaud your recommendation.I have two 65's being restored to concours even the fuel lines and all the other small bits that are unique $$$.The webers are pricey to set-up as well but there are much more webers than solexes.Wondering if the 356 guys with solexes can help.But your set-up does not sound out of line maybe even cheap.Really to properly sort and tune any mechanical system is constant maintenance even MFI.
raj

I won't contradict the notions of supply and demand - moreover, I think what I was trying to communicate supports this. The upshot of supply constraints driving prices is that there comes a tipping point when the aftermarket will step in to absorb demand. In some cases, like linkages and fuel lines, this is happening. This is also taking place in regard to the shops that can now expertly handle rebuilding these carbs. I can think of at least 4shops today that can do this, where 5 years ago Harry Bieker might have been the only one.

In the meantime until the PMO equivalent for Solexes comes online, my lofty goal is to simply drive awareness that we all need to stick together.

[kenikh]

well , you need to applaud the benefit of solex's over webers to really tip the scale.I love solex's when set up properly.So,you need to preach the benfits......come on share

I'll simply link to what I've said before:
http://www.early911sregistry.org/for...l=1#post459604

And to add a few more "hands on" observations:

• Solexes just feel smooth. The difference is tangible compared to Webers, but can't describe it in words.
• Solexes are prettier than Webers - this is of course qualitative, but there's art in their balance of simplicity and complexity.
• Complexity - just take a look at the number of linkages these carbs use!
• The flat spot in the transition circuit is real, but not a huge issue. Some tuners have figured out the secret sauce to addressing it.
• These carbs need isolator spacers - this solves one of the original issues of heat soak volatilizing the fuel in the float bowls.
• The over-rev dampening diaphragm sucks...remove it or disable it. It was only there for emissions purposes and can lead to annoying laziness on throttle return to idle
• Adjustability - Solexes are a collection of six, single barrel carburetors and you can tweak them like crazy
• Adjustment - As six individual carburetors, they can be a total PIA to adjust
• The Pierburg mechanical fuel pump is an Achilles heel - the action of the cam on the actuator rod plays havoc with stable adjustment. There's at least on solution I know of in development, but until then, be diligent in keep rod length in spec.
• Overflow fuel recirculation system is often referred to as a fire hazard, but has an added benefit in that you can fit a fuel cooler to the system pretty easily.
• The fittings on the fuel system are generally uncrimped. This is not generally an issue, but if the mechanical fuel pump starts pushing too much fuel to due adjustment creep, in extreme cases you can end up with fuel spewing on your motor. Not good.

Regardless, I find them to be a more elegant and purpose built solution to 911 fuel induction than Webers. And they are cool.

[304065]

Are you saying it's time to start hoarding Zeniths?

[kenikh]

Are you saying it's time to start hoarding Zeniths?

It's time to start hoarding everything with a 901 part number, apparently.

[kenikh]

well,even flat spots can be gotten rid off and can get 200hp.i believe them.I believe the FIA requires the solex's for racing

http://www.duel.nl/specializations

raj

Correct and you can get these issues addressed in the US, instead of The Netherlands now, as well. As far as the flat spot I was talking about - that isn't actually correct: it is more of a minor hesitation on the transition circuit. IIRC, modifying the emulsion tubes is the proper fix. For those who aren't familiar with what the function that an emulsion fulfills, here's a solid primer, borrowed from another site:

As the throttle plate is opened further the main circuit comes into play...

Fuel enters the bottom of the emulsion tube thru the main jet.....

Air enters thru the main air bleed jet in the front of the carb...

the air and fuel are mixed into an Emulsion in the emulsion tube before it passes up the tube past the needle jet and needle into the carb venturi and down the intake chasing after the idle circuit fuel....

the size, number and position of the holes in the emulsion tube affect the fuel delivery....

More holes = more air = leaner mixture
more holes at the top = leaner mixture at low speeds
More holes at the bottom = leaner mixture at hogh speeds

If you change emulsion tubes you need to put a matching needle in and it will also have an effect on the main jet size and quite often the pilot circuit thru the just off idle response

needles, needle jet, emulsion tube (size, position and amount of holes) main air bleed size and main jet are all closely linked......changing one can affect the others...and ALL have an affect on the fuel delivery to differing amount.

As you might imagine, altering the emulsion tube's design can easily adjust the fuel atomization and efficiency at different loads/RPM.

[304065]

It's time to start hoarding everything with a 901 part number, apparently.

Kenik, your impassioned plea resonates strongly with me, I think I am going to trade my overpriced Solex/Pierburg dual pump for some overpriced SWB toolkit bits.

[kenikh]

Kenik, your impassioned plea resonates strongly with me, I think I am going to trade my overpriced Solex/Pierburg dual pump for some overpriced SWB toolkit bits.

Indeed! I've been trying to leverage a barter economy on parts for a while now.