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Discussion Starter · #1 ·
Here is a brief synopsis of pu

Here is a brief synopsis of putting 40 DCNF Webers on a 3.2 for anyone that is interested. My reasons for doing this stem from a lifelong love and association with these magnificently elegant carbs on Alfas, improved long term reliability, the elegantly simple DIY repair requiring no special tools with the improvement in power, throttle response and sheer personality from retrofitting the classic Ferrari OEM induction. This is not an original idea of mine, as the Porsche 911 community has been retrofitting Webers to Bosch K-jet cars (2.7 and 3.0 liter) with great success for years.

The key parts are four beautifully cast manifolds that fit the 3.0qv/328 head from Frank Capo of Modena Engineering in Australia. I know both Carobu and Durable1 both do business with him, but I found my manifolds at Blackhorse. Be sure to trim and match the stock gaskets to the intake ports. Only a small vacuum tap was needed for the ventilation control system, as the Mondial’s ABS brakes do not require a vacuum line in this application. Everything actually just bolts up like it was original.

Four new commonly available Weber 40DCNF-12s were purchased as well as the large Facet fuel pump used as a replacement for the Ferrari Corona unit. I will make a VERY VERY long development story short by saying one right answer is setting up the Webers with 34mm venturis, 135 main jets, F24 emulsion tubes, 190 air correctors and 53 idles. It of course depends as well on what cams, air filter and exhaust you have. Stock K-jet cams were used, as well as a stock early 308 airbox, which bolted right up (Frank Capo is a genius), and a custom free flow exhaust was fabricated using a Dynomax muffler and four Ferrari Daytona resonated chrome tips. The last bugaboo, the linkage, was fabricated with parts from Pierce manifolds and original 308 carb arms.

Best chassis dyno numbers obtained (although with 36mm venturis) was about 242 rear wheel hp, which with common 17% loss correction places it at about 290 flywheel hp (Factory rating of 260). The sound of the 3.2 liter 4 valve engine with Webers is simply not comparable to the original Bosch K-jet injected version. It is a magnificent awe-inspiring sound.

This is a very easy retrofit to do for an amateur, requires no special tools, and really adds to my enjoyment of the car


Discussion Starter · #2 ·
Very nice synopsis Russ &

Very nice synopsis Russ & excelent photos!!!


Discussion Starter · #3 ·
OBTW Details -
The fuel pump

OBTW Details -
The fuel pump relay will have to be wired around so that the pump comes on as soon as the key is turned to the on position

In a Mondial, if you use a 308 airbox, the metal fins on the inside of the engine bonnet must come off.

As we said in another thread, late stock 308 air boxes can be made to flow much better by removing the meshed insulation.

Did try it using four separate carb air filters, but the stock cool air system is superior I now feel due to hot engine bay air issues with the separates. What a snarl, though!

The facet pump does not need a regulator in an open circuit application. Holley regulators are asking for trouble at low pressures - don't ask me how I know.

Not sure you can tell, but the engine bay now has a lot less 'stuff' and great deal more room to work.

A Weber conversion and the single Unilite distributor shown elsewhere in this section are a DIY guy's dream come true.

best to all
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