Do you need a wastegate or can you just have a blow off valve?

 

Depends how long you want your turbo to last..

Generally speaking they are called pop off valves when used in a way like this to limit boost.

Using a POV you will overrev your turbo very quickly, some racing teams in australia started using them instead of wastegates for a little while but then quickly decided to go back to using a wastegate.

 

Ok so i have a turbo a garret m24 that has a internal wastegate, what is this? i still dont exactyl udnerstand everything.

 

Well I certainly hope your not planning to put that turbo on a rotor, because its waaaaay too small, M24's are generally used on a around 2ltr piston motors, they usually have a T3 style 0.8 A/R ratio turbine housing. Too small.

Re: the internal wastegate bit, I don't exactly understand your question, an internal wastegate is a wastegate. just its internal to the turbine section of the turbo, not like an external wastegate, this is very common practice on turbos released in factory cars, and/or small turbos in general.

 

you need both. they are totaly different.

 

Dont ya mean you need a wastegate or a wastegate and a BOV

 

what is this gold thing?

 

it would kinda help if i posted the picture huh

 

You need a wastegate and a BOV. A wastegate "directs" the exhaust out of the turbo when it detects that there is enough...like it keeps the turbine from spinning too fast. A blow off valve releases boost pressure when u let off the gas. And I hope u don't plan on using that small of a turbo on ur RX7 (or anything with more than 2 pistons lol...maybe it would work good on grandma's geo metro ).

 

The wastgate vents exhaust gasses past the turbo so it doesn't over rev. Internal ones are built into the actual turbo housing, while external ones are on the exhaust manifold. Blow off valves are on the opposite side of the turbo, controlling/limiting your intake boost pressure.

 

speedfreak03--yer a faster type than I...lol

 

Your picture doesnt work..mainly because the link is to this thread..

Anyway, I dont feel that you really understand what a wastegate, or a BOV is. A wastegate is a device that is used to vent exhaust gases around the turbos exhaust wheel, so that it stops producing more boost. If a turbo did not have a wastegate, it would just boost uncontrolled, higher and higher. Wastegates on most stock cars are internal (inside the exhaust housing of the turbo) Once a certain boost level is achieved, it is opened up and exhaust gas is vented through it so that the turbo maintains that boost level.

A blow off valve is used to prevent backpressure from damaging the turbo. When you are on the gas , and the turbo is producing boost, it is pressurizing the intake stream. When you let off the gas, the throttle plates close shut, and all of that pressure builds up, and could press against the turbos compressor housing, causing damage. A blow off valve vents this compressed air, so that it doesnt happen.

In short, you need both. Hope that helped.

*edit*- you all type too fast..stop it

 

 

You don't need a BOV, many stock vehicles ran without a bov or bypass valve, you will just simply encure back pressure on the compressor shortening the life of the turbo. A wastegate you doo need however otherwise your turbo will spin like mad, and it will kill super fast!, also it will stil take time for your engine to wind down even with a POV open, compressed air still manages to getinto the intake.

 

That gold dome is the wastegate actuator. See the rod that is coming from the back of it, attaching to a little lever on the turbos exhaust housing? That lever connects to a little flapper door inside of the turbo. That is the wategate. When a certain amount of boost pressure is sent, that actuator pulls (or pushes, dont know exactly how that on is set up) the rod, opening the wategate, and venting exhaust pressure around the turbos exhaust wheel...limiting the boost that can be produced.

 

lol yes when i am typing something im interested in then i type fast otherwise im slow as molasses