Exhaust Manifold Modifications

Just want a few thoughts on what I'm doing here. Not seen anyone changing flanges on manifolds often. Probably because you can buy them how you want. But I can't spend £1k on a pretty manifold, plus GE manifolds aren't common place - unless it's a cheap 4 bolt design (that's twisted and won't even fit anyway).

Looking to move my waste gate position.

NA-t manifolds typically have a 4 bolt flange bottomside as shown;

I want to cut the 4 bolt and go v band, easy enough hopefully;

Benefits include (hopeful) reliability, ease of spring change and larger diameter flow.

I've currently got a 4 bolt adapter to vband. However, I had issues on the last dyno for 417hp and ran 18psi, was on a 7psi spring and no controller. Boost creep happened visible on dyno. Due to reduced flow, I didn't get much power. Area diameter of allowable port on wastegate was what Austec said at the time.

Haven't measured it recently, but though I'd just go a better waste gate anyway PLUS wanting to move the location to topside, instead of bottomside. Anyone changing wastegate spring will know the pains. Due to the location of the bottomside wastegate it's a serious pain in the a** doing work on it from under the car. Commonly, wastegate issues mean downpipe, turbo and manifold removal. Even more of a pain for those NA-t setups still running overhead intake as that'll mean most your piping and TB in this area. PAIN!!!

Though I've got a front facing intake, I want a topside v band waste gate position;

http://www.garagewhifbitz.co.uk/media/catalog/product/cache/1/image/500x500/9df78eab33525d08d6e5fb8d27136e95/w/h/whifbitz2jzmanifold_singlewastegate.jpg

While doing this, I'm hoping to also add a few braces;

Considering the twin waste gate output too, but so many people do it, is it worth it??

Obviously it won't look at pretty as these artwork style Whifbitz manifolds.

The final item to review is to port the manifold. Now, I won't be removing much material due to it being tubular I'll just weaken weld zone's or port right through the side of the tube. I'll be trying to smooth the insides, attend to any weld zones but was going to weld any branch areas with little material and create split lines. IF I can get in there that is. Thought's on any changes like this? Minimal I know, but the intake side has had loads of work, this needs flange adaption so thought I'd tinker with it anyway.

Every little counts. Even gasket matching and some clean surfaces right.

Is your manifold twin scroll?

You'd have thought XS power would just go V-band like nearly every other manifold on the market!