Thread: Any interest in divorced wastegate O2 housing/downpipe combos?

I agree. I mean how large is the typical exhaust wheel us smaller turbo guys have anyway? I am sure a nice flowing 2.5-3in piece would dwarf the exhaust outlet on the turbo. Its gonna flow a heck of alot better than the stock one anyway. I will def. be down for the one piece unit. Just my .02.

Thanks,Jon

One thing to consider is that when you're really on it hard the wastegate is going to be open and all that gas volume that would normally be flowing through the stock elbow is eliminated from the stream. That advantage coupled with the smooth pipe and larger opening makes me think 2.5 for the elbow is going to be sufficient and not cause it to be too restrictive.

I agree, 2.5" is fine.

One request though, mind putting two O2 bungs in for wideband users, or making it a request option?

Thanks,
John

im cool with 2.5", also i was gonna suggest a 2nd o2 when im ready to purchase too.

the wideband thing is a good idea for the 1 piece. 2.5 to 3" would be ideal for those of us with 3" mandrel bends ready to be made into a downpipe...

I remember reading somewhere that if you put the wideband O2 sensors too close to the turbo they have a significantly shortened lifespan due to the extreme heat.

As for the 1 piece, since that is what I am interested in, I doesn't bother me about being 2.5" by the flange since it will flow better but as long as it gets to 3" I'll be fine with that.

Well, like I said, the O2 housings I think will have to be 2.5". The one piece dp's though, I can do a flare and run them 3" all the way back. What restricts the O2 housings from being 3" is the fact they have to go back into the dp flange which is right at 2.5". The benefits of making it 3" just aren't there.

Like Matt said above, not only are the open wastegate o2 housings going to benefit from much lower backpressure at the turbine, but overall flow of a mandrel bent o2 is going to open the system up. Even the housings that recirculate are going to create gains just from a larger internal volume and cleaner internal surface.

I think it's the best option. 2.5" for the elbows, and 3" if you want to go with a full dp. I can even vband the dp's at the o2/dp connection point to essentially make it two piece if that's a benefit. The vband will add a little cost, but if it helps with install or workability I can do it.

I can live with a 2.5" o2 housing, without a doubt. Especially knowing how restrictive the stock unit is a 2.25".

After looking a bit, titting that cylindrical block off in this housing would seem that it would have to be 2.5" right there... any bigger and it wouldn't fit in the housing.

Again, 2.5" should be plenty big enough.... Look at the exducer of the turbine wheel... This is on a t25, but EVEN on a t28 it only measures around 48mm... which is less than 2", even the big part of the wheel is just over 2". So if its seperated... it will be fine.


Anything.... i mean anything will flow better than hot air going through this...


And, here is where it gets all chalked up... so, there you have it.