[DeTomaso] IDA Webers

[JDeRyke at aol.com]

In a message dated 7/23/07 4:50:18 PM, wkooiman at earthlink.net writes:

<< Yes, I have been considering Webers.  I love the way my car runs right 
now, but a single 4 barrel is boring.  Fuel injection with TWM Induction throttle 
bodies would be a challenge, but a little too modern for my taste.  Webers 
would be just right. >>

Didn't mean to imply that Webers don't work, Will. Its just that they're 
expensive, fussy to tune, difficult to keep in tune once you find a setting that 
works, and expensive/time-consuming to achieve both good power and decent 
mileage. Drilling jets during initial tuning only works to find the jet size you 
need at each point, then you buy the factory jet that matches the hole you 
drilled. If you overshoot the desired size, brazing the hole up and re-drilling 
also works, temporarily. And to run air cleaners, you really need to look for 
paper filters. The common foam ones soak up fuel from the very powerful reversion 
pulses that keep a cloud of fuel/air hanging over the itop of the carb. This 
happens whether there's an air cleaner or not- all carbs meter fuel into an 
airstream regardless of the direction of the air flow. Then, a minor backfire- 
very common when not thoroughly warmed up since there are no chokes, only an 
enrichment circuit on one barrel that pours even more fuel in that hole- will 
ignite the soaked foam. The flame usually melts the small aux venturis that 
protrude up, since they're zinc, not aluminum. Melted zinc then drips down the 
very short intakes past an open valve, freezes and cracks a piston on the next 
revolution of the engine. I've done all this multiple times, and piston 
replacement due to a minor backfire is no fun.  Weber equipped cars need a Halon 
extinguisher aboard even more than Panteras normally do! 
Finally, most Weber- equipped cars also need a vacuum reservoir and check 
valve system for power brakes & distributor advance, since the total volume of a 
single carb barrel is so small the vacuum signal is close to non-existent for 
each stroke. Ganging all the barrels on one side together for 'total vacuum' 
doesn't work either, because the reversion pulses tend to cancel each other out 
so your total vacuum is about zero. 
Bottom line- find a local tuner with a good record with street-tuned  Webers 
first, then go looking for a set. $2500 is a fair price these days for 4 
carbs, an intake and sorted-out throttle linkage. All else will likely be extra. 
Good luck- J DeRyke<BR><BR><BR>**************************************<BR> Get a 
sneak peek of the all-new AOL at http://discover.aol.com/memed/aolcom30tour
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