I have the BR 440 kit. I was curious if it's possible to convert it to use an external wastegate? if so is ther an easy way to do it?

 

It's not pleasent to weld into a cast manifold.

And even if you can, you can have issues with cracking due to thermal expansion.
(A cast manifold will expand at a different rate then the flange/pipe welded to it)

If you do something like this, you might want to invest in a cryo-treatment. It's kind of like shot peening. The process heats or chills the metal to one extream, then another. When all is said and done, the metals should not break away from each other.

(expensive though) Come to think of it, it's probably cheaper to just go with a tubular manifold and repair it once in a while if that cracks.

 

Or.....

You could weld the external wastegate on to a custom O2 housing. Then you would just need to weld the wastegate door shut and standby for boost creep that is common with external wastegates.


Why are you wanting to do this, again?

Just curious.

 

too much work for too little benifit.

 

i thought external wastegates get rid of boost creep..

 

How would that work? You need to remove exhaust gasses before the turbo, not after....

 

I've had them on other cars and never liked them. They seem to flutter a bit more than internal wastegates. Of course, I might have just gotten a couple of bad ones. They never seemed to work right for me, be it with a T-25, a T28, or two 16G's. Who knows.

 

Then how does an internal wastegate work? The flapper valve is on the exit side of the turbo, just before the downpipe.

 

Like this....

 

doesnt the RNR turbo kit use a external wastegate

 

That looks like a sweet *** set up. Where did you find it??

In answer to your question, an interal wastegate bleeds off exhaust gases prior to the exhaust turbine (not after). The one in the picture is redirecting exhaust gas at the same point (port) as the internal using a divorced style set up.

 

I was just curious if it can be done and why the BR 440 kit didnt come with it like a lot of the other kits i see.Just trying to gain some more knowledge here.

 

Think about where the flapper door on an internal wastegate is. It's right there at the flange to the O2 housing. That flange is AFTER the exhaust wheel. The flapper isn't up near the exhaust manifold.

That O2 housing is from Victory Performance and is for a 1st Gen DSM.

The reason I said it was best to go on the O2 housing was because it's a pain in the *** to weld on cast parts, plus with it on the manifold, you have to worry about unequal pressure due to the WG being closer to one of the ports than the others.

Here:

http://www.dsmtuners.com/forums/showthread.php?t=134639

Read that. It pretty much sums it up.

Like I said, I had mine on the exhaust manifold and had a hell of a time trying to keep the thing stable, no matter what MBC or EBC I used, and no matter what turbo I used. I think it was just me "mixing and matching" parts that led to the demise. If I would have stuck to one tried and true upgrade path, I probably would have been alright. Also, I was trying to use an external wastegate with an atmospheric dump tube and a GReddy Type S BOV that was vented to atmosphere on a car that was still driven on the street. The more I think about it, the more I think that it was probably my errors along the way that caused things like the boost spike/creep that I had.

 

Cost savings. It isn't needed, so it isn't included. Dave Buschur is a no-nonsense tuner. That's why I have been partial to his stuff for quite some time.

 

Yeah. That is why I have all of his parts as well. THnx for all the info.