Stupid Holley question, but I'll ask anyway...

Is there a way do convert a 600 cfm holley into a 450 cfm? If not are any parts interchangeable?

 

No there isn't, only the bowls are the same.

 

While a 600cfm may seem too big for your application the vacuum secondary version can be made to work on smaller displacement engines at little easier than a mechanical secondary unit. Is this a carb you already have and what are planning on using it for?

 

Try a 9.5 or 10.5 power valve .I used that set up on a 307 and it stopped fouling plugs at idle.307 only came with a 2 barrel .Also post your application and motor size.

 

The power valve is set up by the amount of vacuum the motor pulls. You can jet it down to work on just about any situation.

 

Put a restrictor plate on the manifold.

 

Unhook the secondaries... now you got a 300 CFM....


alright that was a stupid holley answer.

 

Man knows his stuff. A plate is quick and non-permanent so if you do not get the results you want just take it out.

If might help us if we had more info on what you are trying to accomplish with your mod.

 

I have (1) 450 and (3) 600 carbs. I have a tunnel ram I want to run on a relatively stock 350 with a mild cam and a fresh rebuild in my coupe. I am trying to put this car together on a budget (nill) so I am trying to use what I have rather than buying another 450. Anyone want to trade a 600 for a 450????

 

how about the 2 600's set up w/o the secondarys?

 

Was concerned that might be too much fuel running the 600's.

 

YES, I did exactly that with my 2 600's. I couldn't afford the high zoot 390's but instead found some old 450 centers at a swap meet for 5 bucks each. I swapped over all the parts and have been running them on a dual quad without issue for years.

 

So I can use a 600 metering block with a 450?

 

I did. At first I noticed idle mixture was excessive - so I restricted the idle p***ages and never looked back. I used EVERYTHING off those 600's. Now don't get me wrong maybe I just lucked into a combination of Holley parts that would work. I dunno. But I still have the car with those carbs - I can get the numbers off the center sections if you'd like. I literally bought them for 5 bucks a piece - out of a pile of them at a swap meet.

 

Those numbers would be a great help, thanks in advance.

 

Anyone wanna trade a 450 for a 600?

 

Well...much to my SURPRISE when I popped off the aircleaner tonight I forgot I had milled off the air horns. ;-( See pic and keep reading...




....but luckily I found my notebook on the car and this is what my notes say:
One is a:
List 4473

the other:
List 4548s

As I said earlier - these centers were swapmeet specials - they "looked" identical and as I recall were factory Ford carbs that were both 450's.