[Tom Vaught]

Originally Posted by Craig Hendrickson

Even though the wastegate is a little more expensive, that's what I would recommend. As a matter of fact, the earlier versions of the TurboForce pressure hat had a pad cast in the side which could be machined for mounting a blow-off valve. The final and best version of the pressure hat had eliminated that pad.

Craig

I remember that Pad.

Tom Vaught

[Craig Hendrickson]

Originally Posted by Tom Vaught

I remember that Pad.

Here ya go, Tom:



On my 1978 Turbo Macho T/A with 1972 455 engine (not the W72 engine), I had both a wastegate and a blow-off valve. I had the last generation pressure hat specially modified by Kern in order to fit the blow-off valve. It was on the other side of the hat than shown in the above picture. It was a belt & suspenders kind of solution to boost control.

[Joe37]

What this car has must be the waste gate, its mounted down under the engine on the exhaust system. I only looked at for a minute or two. It has a small hose running to it, right dead center of the top. I assume the boost pressure opens this at a set point. Is it adjustable? The whole top seemed to rotate but it could just be loose or defective.

So if I understand this right, the waste gate controls the exhaust going to the turbo. As boost comes up the waste gate opens at a pre set pressure thus dumping excess exhaust away from the turbo. This seems like a good choice as the turbo would not need to work any harder then needed.

A blow off valve is on the clean side of the turbo and acts like a pre set pop off valve. Once it opens, the turbo can still wind up due to the excess exhaust build up in the system thus over speeding the turbo shaft. Does the turbo know the blow off is open? or does it continue building boost only to have the blow off dumping the excess away? I can see how it would limit the amount to the engine, but it seems a funny way of doing it.

Thanks for the lessons,

Joe

[twov8sandat4]

Originally Posted by Joe37

What this car has must be the waste gate, its mounted down under the engine on the exhaust system. I only looked at for a minute or two. It has a small hose running to it, right dead center of the top. I assume the boost pressure opens this at a set point. Is it adjustable? The whole top seemed to rotate but it could just be loose or defective.

So if I understand this right, the waste gate controls the exhaust going to the turbo. As boost comes up the waste gate opens at a pre set pressure thus dumping excess exhaust away from the turbo. This seems like a good choice as the turbo would not need to work any harder then needed.

A blow off valve is on the clean side of the turbo and acts like a pre set pop off valve. Once it opens, the turbo can still wind up due to the excess exhaust build up in the system thus over speeding the turbo shaft. Does the turbo know the blow off is open? or does it continue building boost only to have the blow off dumping the excess away? I can see how it would limit the amount to the engine, but it seems a funny way of doing it.

Thanks for the lessons,

Joe

From Tial's website:

Plumbing wastegates with manual boost controller to set boost:
http://www.tialmedia.com/documents/w..._wginstall.pdf

Plumbing Blowoff valves:
http://www.tialmedia.com/documents/w...bovinstall.pdf

Should give you some more ideas.

This is how my AWD Talon is setup, except I run a pair of wastegates instead of one.