Its my understanding that the composite carb helps prevent vapor lock by not acting like a heat sink.

But, it still appears that your high-end engines are running aluminum carbs. I was also told that composite carbs are less expensive to create, which keeps the engine selling price down.

What are your experiences between the two?

I prefer aluminum. Composite carbs are prone to leaks and I have not found them to really help with vapor lock. Even if the carb does stay cooler, the crank and case still get hot enough to boil off the fuel and will still vapor lock. Of course, proper tuning and cooling will avoid the problem either way.

I too prefer aluminum.But cheap aluminum carbs are just as bad as cheap plastic carbs.

A good composite carb like Sirio's .12 carb beats an aluminium carb by far.

I really think the aluminum carb with heat insulator has the best of both worlds... Its aluminum, and prevents the vapor lock....

Just my opinion.

In my experience the composite carbs are more prone to leaks and problems but they do seem to help a lot with vapor lock.

Sirio did swap to aluminium with their .21 carbs and did solve some issues. Isn't it just that today a milling machine and a piece of aluminium is much cheaper than a plastic molding machine?

The most crappy carb I have ever seen was the old Mega P5 carb, it had always trouble finding the right adjustment without hick-ups or jiggering. Most people did seal anything off with a kit or special sealing paste but finally the needle was the cause, you had to shorten it. I think there are many other things on a carburator making a carburator good or bad.....

I doubt I am good enough to even notice the difference

Thanks guys.

+1

You'll notice it when you have flamed out and your car won't start because it was a bit too hot...

Or when it wont tune right at all because it's leaking at a seem.