Replacing a twin choke Solex 40 PAAI with a 3 choke Solex C35-P3 carb

[FERGTS246]

Hi, I'm thinking about replacing the factory fitted twin choke Solex 40 PAAI with a 3 choke Solex C35-P3 carb on my 823.00 engine.
I just want a bit more oomph!. Does anyone know if the 3B models of Flaminia had a different camshaft to the twin choke Solex models?
Any other advice/thoughts would be welcomed.
Thanks in advance
Chris

[Richard Fridd]

I would like to know too. 'Triple carbs don't work with the associated camshaft' was a previous reply to my 'flaminia'  thread. Not sure if this applies to Webers or Solex or both. Looking forward to any posts on the subject of your proposed conversion. Do you have the parts to proceed? Richard

[FERGTS246]

Richard, I haven't got the parts yet but an Italian friend may be a supplier. Before I commit to buying the parts I want to fully understand what's involved to get the benefit of the Solex C35-P3 carb.
Chris

[willoroe]

Chris,
Sounds like an interesting project.
Wim Oude Weernink has got an appedix with model specifications in the new Flaminia book.
He doesn't show any cam timing difference between the 823.01 engine and the 823.02/03 (3B) engines, so it looks like it is a bolt on change once you have the right manifold.
The increase in power is 9bhp, 128@5800rpm instead of 119@5100rpm. He shows a drop in torque though from 19kgfm to 18.7kgfm both at 3500rpm.
So it might not feel like there is much of a change following the conversion. It should be more free revving, I suppose, and might sound more exciting! I would be really interested to know how it turns out.
Willo

[Richard Fridd]

I haven't got the book yet Willo. How many different cam profiles/ timings does the appendix mention? Just wondering how to identify which goes with which carburettor selection. Bolt on conversion sounds good, so any improvement or otherwise could be experienced same day, with easy reversal I suppose.  Richard

[chriswgawne]

There is no doubt that the triple carb set up looks nicer that the single one but for such a modest potential power increase ( 9bhp) have you considered simply gas flowing the heads and changing the carb to a modified Weber 40DC type with larger chokes, jets  etc? ( I believe its slightly easier to mod a Weber than a Solex 40PAAI). Just a thought.
Chris

[Richard Fridd]

That's interesting Chris, do you,or anyone else, have details of what is involved regarding the Weber DC? This is something I would be interested in trying. Richard

 Having read this again, could this involve a single DCNL 35 or DCN40 on the existing Solex manifold? Richard

[Charles Frodsham]

What about one of these……Nardi inlet manifold for Flaminia…

https://www.ebay.com/itm/164107431480?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20200818143230%26meid%3D8190ea4ab0d8428c9e63e53afcff5653%26pid%3D101224%26rk%3D2%26rkt%3D5%26sd%3D163680574213%26itm%3D164107431480%26pmt%3D0%26noa%3D1%26pg%3D2047675%26algv%3DDefaultOrganicWeb&_trksid=p2047675.c101224.m-1

Shame about the price!

[GG]

From the manual; best place to look about possible camshaft changes would be in the parts book. It appears in this version of the manual, there were only single 2 barrel Solexes (berlina) and three two barrel Webers (GT/Sport). Triple barrel Solex doesn't seem to be listed.

[Kaha]

The partsbook lists 4 different camshafts:
One for the very first berlinas (813.00) first berlinas, one for early berlinas (813.10), one for the 3C and another for the rest (later berlinas, single carb Touring and Zagato and all PF coupes (both two and three barrel Solex))

There might also be a clearance issue. The 3C had both different distributor and termostat housing to clear the bigger carbs, I don't know if that is the case with 3B?

[Richard Fridd]

I think it's the air filter housing which requires the clearance, and I am wondering how to identify which camshaft is which? I have one in the car, one in the spare engine and one in the store. Also, the manual includes camshaft replacement in the operations with 'engine in the car' section. Richard

[FERGTS246]

Chris, a modified Weber 40DC type with larger chokes, jets  etc sounds like a good idea. I'll look into that.

When you write "with larger chokes, jets etc" - do mean the Weber 40DC has larger chokes and jets than the Solex 40 PAAI as standard, or that I'd have to put them in?

With the 3B carb, I'd have to find some throttle linkages and water thermostat housing.
Thanks for this info

Chris

[FERGTS246]

Willo,

Your points about the slight torque reduction and minimal power increase does make a conversion a bit of a waste of time and money.
I'm not into the look and sound without a noticeable bit more oomph.
I'll look into changing the carb to a modified Weber 40DC type with larger chokes, jets etc.
Richard Fridd mentions a single bodied Weber DCNL 35 or DCN40 possibly fitting on to standard Solex C.40 PAAI manifold. Do you know if either would with a bit of tweaking?

Thanks
Chris

[Richard Fridd]

Does anyone else here have experience of this Weber fuel injection system? Single body replacement for downdraught carburettors. I just saw it in C+SC today.  Richard

[lancialulu]

Is that Jenvey technology? I am familiar with the Jenvey version of a Weber twin choke form factor injection unit. Works well with the right ecu and mapping. Something outside the scope of a diy solution unless you have a rolling road in you garage.