Smith-02

setting the spring a pound or two under your wg seems like it would be the best way without reducing ability of the flapper or choking your ---- up

HiProfile

Actually I didn't think of the backpressure opening the valve, but its not as bad as you might expect. When you do the math regarding the area the diphragm & valve each have, 2psi pushing the valve up requires 1psi on the diphragm to counteract it. You'd also only see 50-60psi in a newer volvo with stock where they use a GT17 on a 5-cyl or whatever the motor they use. A PR or 2:1 is more what you should expect - 10psi intake = 20psi exhaust. What all that means is your spring would probably open at 1.5x the rated spring, 2x at the most. Your little bit of air you tested with is not enough since you didn't used a regulated source with constant flow. That's how the engine provides it. If nothing else, cut the spring - they are sompressed by half their height inside. Just don't pinch the cheap CDM diaphragm when you reassemble it.

As far as concerns of gas flow not letting it open or pushing it open, butterfly valves behave in a way that negates that. Like a lever, one side wants to be pushed 'open' as much as the other side is pushed 'closed'. It also doesn't stop ALL exhaust flow (just half), and has a little pressure behind it. It will not be an issue.


To whoever said to use brass bushings, 2 issues. 1) Bronze melts just above the temps in question. Red-hot bronze isn't a great idea for a bushing. 2) bronze busings are what are used for cutouts, and even the dry graphite-infused ones are only good for 500F. He's dealing with ~1500F gas that's also pressurized. Its also powered pnumaticly, so there's no issues with burning out a motor.

CXyD

I beg to differ bronze with high levels Cu melts at above 1000deg F and at the foundry I work at we have to get well over 1500 deg F to get flowing as a liquid and some engineered bronzes have to pour above 2200 deg F.

I really do not think it will leak much if there is tight tolereances between valve shaft and cast turbine housing.

onlyflash944

in for updates

perpetu8

subscribed

TurboGuy

awesome

shoyass

Update?

repherence1

what happened to the pics?

redlinevtec

nice

chronic

Sorry, I haven't been around here for a long time. And a few months back I decided to finally organize some pics in photo bucket, thus ------- up links.

Here are the pics again. Plus a vid of it working.











The first bit and last part of this vid is just fluff since I needed to get in and out of my car to turn the camera on. Could have edited it out, but what ever. Just shows the valve open as it boosts.



I dont know if I wrote this in here or not, but the way I wound up controlling it was with no spring at all, and I relied solely on vac/boost pressure. What I used to adjust it was one of those bleeder style boost controllers you get off ebay

I have it backed almost right off, so that you can barely blow through the hose to open the valve. It makes the valve open smoother. With it adjusted so the valve opens quicker, you get a big jolt in power.


So, It has worked all year. I checked on it once a few months ago to see if its melted. But it was good, soon here when I park my car for winter I'll take the turbo off again and see if its still in decent condition or not. I am pretty happy with it.