Im looking to boost prep my 51ida weber (7-10psi max on stock s5 turbo). From what I read I need to do 2 things for sure.

1. Vent the fuel bowl into the carb hat so it sees the equal pressure. (Line from fuel bowl to carb hat area?)

2. Swap the brass float for a plastic float. Because the brass float will crush above 6psi. The plastic float ot good until 20psi.

Other things I have read are unclear. Its obvious that i need to seal any and all areas that can leak. But what areas do these include?

1. What else besides the "hat" needs to be a sealed?

2. Do I have to seal the throttle shaft?

3. Is there any other modifications to the weber that need to be addressed?


I have everything else ready to go. I just want to be sure I get my weber in order before setting it all up.

 

by what you said in your post i think you are good , the webber is a great carb to blow through , I think you should be more worried about your timing ( weld the advance ) , so you don't advance under boost

 

i bought an engine with a blow through weber setup already on it. i noticed something cool in the float bowl that you may be interested in.

the bowl was embiggened by cutting one wall out and using the dead space near the throttle bores. i can take a pic if youre interested. basically just means there is more reserve fuel for those super soaker moments.

 

Thats already done on my Weber. I believe all the 51ida Webers come this way. Since most are used on full PP motors and need the extra fuel reserves.

I wouldnt mind if you posted a picture though. To compare...

 

does it have the 3.3 needle valve? neoprene top gasket? what carb had do you have for it?

 

Yes and yes. And I made my own hat.

 

perfect, your good to go then, I was reading the float bowl is enlarged on it too, very nice..
now, get a Mallory 4309 fpr and a walbro 340lph, or a bosch 044 fuel pump and your fuel system is done

 

I have the Mallory 4309 regulator and Mallory series 140 competition fuel pump.

So no need to seal the throttle shaft? This is the part i'm mainly concerned about.


And venting the fuel bowl into the carb hat so it sees the equal pressure is as easy as putting a line from fuel bowl to carb hat area?