Karl Buchka

My brother and I spent a few days on and off making this thing. Finished it last night.

It's made from two Stromberg float bowl covers. Broken down:


The top of the upper cover has been turned down and threaded:


The inside has also been turned down to hold a spring:


Bottom cover has been mostly hacked apart and also has some slits along the perimeter (I love the indexing table):


The tube has a snap ring that places it flush with the face of the bottom cover:


Rubber membrane with a spring perch/50mm disc:


Tube goes inside the bottom cover, membrane goes on top:


Then with the spring on the membrane's perch followed by the top cover and the threaded bushing, you end up with this:


Weld the tube to your charge pipe and run a vac signal to the threaded bushing and you've got yourself a blow off valve.

c5R

not to bad good job on the diy

srmofo

interesting....do you have any idea what the spring rate is?
how many hours involved?
cost on materials? did you buy the float bowls new or just have them laying around?

good job looks nice, let us know how it works out

Karl Buchka

Thanks. This is a proven design, so the only thing that should need tweaking is the spring.

No clue on the spring rate. I've never made one before and I'm still a rookie with the mill and lathe, but it cant have been more than 20 hours of labor.

It hasn't cost me anything. Materials were dug out of the junk bin and the float bowl covers were free (came off a couple of old carbed volvos).

-RedneckDave-

That is awesome fabrication. I would love to see how well this works out.

HiProfile

Just make sure you polish/round off the ends of the metal 'seat' the diaphragm sits on - you don't want it rubbing a hole in it. Ideally it would be shaped like a velocity stack's inlet. Less chance for cutting the rubber, and more seat area to seal against.

Very cool, almost as cool as your brick project!

irishflame27

pretty neat!

srmofo

what this brick project hiprofile speaks of?

scartail

Very inspiring!

Reminds me of St. Basil's Cathedral in the Kremlin.

weiRtech

cool. i don't think that spring will be strong enough though. i made my own bov once and the spring i used was a larger wire than that and it leaked below 8psi.

Karl Buchka

Thanks!

I'll definitely make sure the edges are rounded off like you suggested. Glad you like the valve and the car.

Linked in my signature. http://forums.turbobricks.com/showthread.php?t=162845

Thanks. I might try to have some heavier springs on hand when I get around to testing it. It doesn't seem like it would leak though, considering there's a net downward force acting on the diaphragm.

weiRtech

i imagine as long as it takes some effort to open the valve by hand it should be ok.

Tony the Tiger

For a project like this, I REALLY want to see videos of this BOV in action!

levelzero

Yeah I'm in on the off chance of seeing this work. Great bit of DIY though.

Karl Buchka

Well, it's not like a diaphragm valve is something I just invented. Thanks.

092eg6

i'd rock that **** !!!!!!!

Smokinsax

you need to get that thing anodized purple.