Here is a set up for a 351c on ebay # 8028038794. That would be kick a$$ on the street.

 

Webbers are great carbs... when wide open. They are not much fun at part throttle or (chuckle) "idle." Now they might suit a Mustang driven only on weekends.

 

How about on a 434 in a 4x4 for the mud bogges?

 

Probably came off of a motor which siezed up due to an excessive amount of silicone sealer which squeezed out from the end seals during the manifold installation and entered the crankcase.

In general any properly functioning and even many not so properly functioning carbs are fine at WOT. At WOT a carb is just a big air hole in the top of the engine that fuel is being pumped into. The trick is getting a carb to function properly from idle to WOT. After all how many street vehicles actually see WOT for extended lengths of time?

Weber carbs are very reliable when properly tuned and that's the real trick. If you look closely at that item you'll notice that each intake runner is individual, there's no mixing between them. The Webers are designed the same way, it's basically 8 individual carbs, 4 of which just happen to be stuck together. When properly tuned a set up like that will outperform 2 4V carbs hands down even though they technically have the same number of "barrels".

That set up will provide massive mid range torque as well as run up to redline in a big hurry. If the reserve on that item is less than $2000 I'd be extremely surprised and if someone gets it for that they're getting a real bargain. Brand new that set up should run almost $3500.

Speed costs money...how fast ya wanna go?