I could do it easily (I think). If I have to I was thinking of plugging the choke shaft holes on the outside then drill small holes from the float area into that shaft hole for reference. I'm thinking that would be perfect. Any opinions on that? It's an Edelbrock 800 1412 carb. Thanks.

Brad...

 

Absolutly, yes they do. How to do that with an Edelcrap I'm not sure, but my advice is to get a Holley. Holleys are much easier to adapt and Edelbrocks aren't tunable enough.

 

The best way for normal carbs to handle blow through supercharging is some type of pressure box like the vortech igloo. The problem you'll have when you pressurise your float bowls to prevent fuel from spouting out is that now your next problem will be sealing the throttle shafts

Marck

 

Sealing the throttle shafts shouldn't be a problem for the newer carbs according to this site.

http://www.vs57.com/carb.htm
So I should be good to go. I may or may not boost reference the fuel bowls. I'll see what happens first. Thanks.

Brad...

 

If you don't boost refrence them then the boost will force the fuel out of the passeges... you'll basicaly end up with less fuel the more boost you run.

There's a few people out there that have had good success with the edelbrocks in blowthrough apps... I'd stick with it until you decide you need to go injected.

 

From what I have read on the internet and the Hugh McGuinnis book is that you would boost reference your fuel pump its self and not the bowls. On a mechanical pump you would boost reference the diaphram side on a return stye pump , if your running a electric pump you can use a 1:1 boost reference return regulator. That way every pound of boost increases fuel pressure by a pound. I dont know if this can be done at the fuel bowl on the carb or not but I always understood as a boost referencing the return line. Far as the carb goes you plug the choke hole and boost reference the throttle shafts which seals them because they are below the ventures. Just stuff I have read I probably dont know what the hell im even talking about. Damnit when is going to warm up again so I can start to beat on my car again. Come on spring time where you at! Drive it like you stole it!!!!

 

You aren’t boost referencing the throttle shaft, you’re forcing air at the boost pressure without fuel in there to replace the boosted air + fuel that would normally get in there and get forced out the shaft, causing a potentially dangerous situation.

To get a carb to work you really need to maintain the same pressure in the fuel bowls as in the throttle bore so that the vacuum created in the venturi’s can actually suck the fuel out, in other words, boost referenced. On most carbs, this doesn’t really involve doing anything since the bowls should be vented to the area above the throttle bores, effectively keeping them at the same pressure (of course, I have rarely touched a carb in my life so in no way do I guarantee that this is the case with all carbs).

 

The float bowl is boost referenced once you install the carb bonnet. The bowl vents are pressurized by being within
the 5 1/8" circle that the bonnet seals.

Your throttle shafts and idle mixture screw may or may not leak.

The top side vent of a mechanical fuel pump needs to be connected to the carb bonnet so the fuel pressure is boost referenced.

 

Where is the float bowl vent on an Edelbrock? I couldn't find it. I figure I'll probably find it when I take the top off to replace the jets. I've never worked on a carb, but from what I've heard and read it's not to hard to change the jets in these. I'll find out soon enough. Thanks.

Brad...