Carburetor Technical Information

[Wolverine]

Was reading this article, thought it had some good points regarding:

1. Smaller or larger carb.

2. Vacuum or mechanical secondaries.

3. Blonde or brunette.

http://www.stangtv.com/tech-stories/engine/race-vs-street-carbs-picking-the-right-carb-for-your-motor/

 

[Don65Stang]

1.) I like a just right size.

2.) vacuum.

3.) brunette(s).

 

[goodnigh]

Good article. Unless you are an all out street racer vacuum is fine, with a light spring.

Despite the math calling for a 574 cfm carb on my 351 it is a Cleveland and needs the

770 I have now. Started with a 600 Carter then to a 670 Holley. When I got the rebuilt

long block with a "mild" cam we went with the 770 Holley. Getting around 50% better

gas mileage with the bigger carb. Go figure. Alas, it is a quench Cleveland and all the

usual rules get tossed. You can stick a tennis ball into the intake port on a Cleveland head.

I am a leg man myself.

mike

 

[Don65Stang]

Good article. Unless you are an all out street racer vacuum is fine, with a light spring.

Despite the math calling for a 574 cfm carb on my 351 it is a Cleveland and needs the

770 I have now. Started with a 600 Carter then to a 670 Holley. When I got the rebuilt

long block with a "mild" cam we went with the 770 Holley. Getting around 50% better

gas mileage with the bigger carb. Go figure. Alas, it is a quench Cleveland and all the

usual rules get tossed. You can stick a tennis ball into the intake port on a Cleveland head.

I am a leg man myself.

mike

That's very interesting Mike. What mpg are you now getting? What is your initial and total timing? Did you adjust the timing around the same time as the new carb install? What distributor/ignition are you running? Did you change anything when the new carb was installed?

 

[goodnigh]

That's very interesting Mike. What mpg are you now getting? What is your initial and total timing? Did you adjust the timing around the same time as the new carb install? What distributor/ignition are you running? Did you change anything when the new carb was installed?

I am judging the gas mileage by how much it took to fill the tank

between stops as compared to what it took last year during the

same road trip. It may be due to the new engine or the proper

size carb for a Cleveland, with a cam. The new engine was installed

and due to the presence of a cam we decided to use a bigger carb.

The new engine acted like it wanted more air. No easy way to

explain that. After the four idle screws were set, by ear, we set the

timing, again by ear. When measured with a gauge the timing was

16 before and the manifold vacuum was 16 in. Have not measured

total timing. I call it 16 squared and the engine likes it.

mike

 

[woodsnake]

Along the lines of carb stuff, have you ever been over here?

http://www.carbdford.com/portal.php

 

[Wolverine]

Never enough info.

 

[TommyK]

I don't understand the philosophy which deems it unnecessary for a high performance (race) carburetor to work well below 4500 rpm. That was the story with my 950 hp until I got done molesting it with pin drills and taps. It doesn't need to be that way.