Vacuum Secondaries

furrystump said
For sgat ever reason 340’s like BIG carbs.

I can't really speak for 340's but my machinist has always told me big block mopars like big carbs because the restriction on the intake side is at the head, so it doesn't want one before that. I can say that on my dyno testing I've yet to find one of my 440's or other peoples that didn't like a bigger cfm carb and a bigger plenum. Currently I run a 950 proform on a performer RPm with a HVH super sucker reverse ball mill spacer. It is like cracking a whip as far as throttle response and it works well under load and WOT as well.

krazykuda said
Slanging match???

You were the one that called the 340 Dart with a 600 vac secondaries a slug...

We built one that will spin the tires as long as you can hold it steady...

Not everybody does quarter mile... Many of us drive our cars on the street and want throttle response and a little fuel economy to go with it...

Could it spin those tires like that with a real set of tires under it? Spinning tires doesn't equate to big power.

You don't tune throttle response by selecting a smaller carburetor. By no means do I think a 600 is too small for a small displacement V8. I make over 450hp with a 500cfm carb on my dirt track engine. Could it make more? Yes. Vacum secondaries don't give you better throttle response or less gas milage. If anything you get better milage as you can control if and when they open. YOu can literally feel the gas pedal when you get to the point they are going to open.

I am a huge proponent of building a car for the street, not he strip. People love to say their car is a street strip car. Even if you raced every weekend that car lives 86% of it's life on the street. This is why I hate overcamming an engine or wanting that radical idle so many think they want.