[Nick325xiT 5spd]

I'm building off of the OBX headers for mine. (Essentially a they are a build kit on the driver's side.) The Ergens are a fair amount of money but have a lot of compromises.

 

[Nick325xiT 5spd]

I will agree and second the fact that the headers pictured are not optimal. But then again, our stock headers are FAR from optimal... so its hard to say it would be a downgrade.

On the assumption that you NEED to get headers for fitment reasons, I see no problems with the ones pictured mounted. If you dont NEED headers, I think the gains will be minimal to non-existent and you would be better off just using the stock bits.

Basically, if you are paying someone to fab an exhaust, the Ergen headers are probably the cheapest solution and they are decent and easy. The modified X5 headers that some folks use for V8 E30 swaps look more like plugs than exhaust manifolds.

If you are prepared to do some serious fab work yourself, there are other options. The Ergen kit is, so far as I am aware, the ONLY off the shelf option that isn't utter garbage.

 

[Nick325xiT 5spd]

Those headers are not ideal. Use the stock header from the S62 if you cant do Evolve or Supersprint.

Stock is not even in the vicinity of an option. They do not fit at all.

 

[Nick325xiT 5spd]

I see 2 different sets of headers in these pics. No? I am not an exhaust guru, but based on what I know and pick up, the set laying on the floor don't look like a great design looking at it from a equal length perspective. I know some applications just can't have equal length tubes due to space, but what is pictured there is drastically different. I think there could be driveability issues with that set up, or at least a power differential between cylinders. The first set, that are bolted on an engine, look like they will work fine. I can't comment on how well they would flow, but certainly don't look restrictive. They are probably better than the OE manifolds anyway. :dunno:

Ergen makes LHD and RHD versions. The major problem is clearing the steering shaft, with less major problems including the subframe, frame rails, and floor pans. Symmetrical headers aren't really an option, short of deliberately crimping the passenger side.

 

[Nick325xiT 5spd]

The next best option would be 4.4i/4.6is headers. They're shorties.

I'm assuming its a chassis fitment problem with stock/SS/Evolve

Have you seen the 4.4i driver's side header? It doesn't flow well in the beginning, but by the time you are done clearancing it to fit, it flows even worse.

I'm going the semi-custom route myself. I've got a set of OBX headers that I'm basically using as a build kit. The passenger side will clear with minimal modifications. The driver's side will require massive reworking. Supposedly, the OBXes are better than than the stock pieces, although by the time I'm done with the driver's side, it'll be VERY different.

Edit: don't forget that the S62 is quite a bit wider at the heads than an E30's frame rails. It is a very tight fit.

 

[Nick325xiT 5spd]

Yes. Many many times. It's more or less the same as the stock S62 header, but angled differently for the E53 as it has rack and pinion/awd in the way vs a steering box. The custom headers in the pics before will flow no better. OBX everything is junk in my experience.

Let me rephrase: have you seen an E53 header brutalized to the point where it fits an E30?

And I agree that the OBX pieces are junky. Like all ebay pieces, they need a lot of cleaning up. They are, however, a very inexpensive build kit and have been shown to make power on an M60. The key is that I could not buy the flanges and the tubing for less than they cost.

 

[Nick325xiT 5spd]

AFAIK, you shouldnt have to do as much brutalizing. They're already shaped for extra clearance for the E53's steering column/rack. Esp compared to the ones on the 540i (pre-TU) and M5. They're shorties and have no precats (the cats are mounted in the Y pipe).

The M60, nor M62 really do compare. Knives to an assault rifle fight.

The answer you were looking for was "no." You have to partially crush them.

And, I'm sorry, but why would the S62 be less restricted than an M60 by the same headers?

 

[Nick325xiT 5spd]

That's what I meant. You cant compare them working on an M60 to them working on an S62.

Why the hell not? The M60 comes stock with the same headers. Or to rephrase, the S62 has M60 headers!

 

[Nick325xiT 5spd]

You think these headers work? Changing them out gives you 25WHP on the low end. That's called COST CUTTING. FYI, only one car with the M60 got those headers. The 740i.

No, I think that the S62 is massively exhaust limited. I'm not claiming that ANY header listed in this thread is a good option! What I find bizarre is that you think that the modified X5 header is better than either the Ergen or modified OBX!

E30 V8 fitment is about choosing less bad options, you don't get to choose from good.

And yes, I know that the 740 was the one that got these headers. The OBXes only fit the 740 without modification, which is where my comparison data comes from.

 

[Nick325xiT 5spd]

OBX is crap, I think pretty much anything is better than their stuff. Even smooshed up OEM headers.

Ergen look like they'd create standing waves at high rpm from how everything merges.

So, again, we know that all varieties of stock headers are a) massively restrictive, and b) not specifically designed for the S62. I'm still waiting for you to provide some kind of reasonable theory or evidence that the S62 is so different from the M60 that headers that provide gains on an M60 will not provide gains on an S62.

In this case, why will the OBXes, which make power on an M60 be worse than the same headers on an S62?

Because really, I'm genuinely interested. If I crushed X5 headers would actually flow better, I'd save a lot of time and effort.

Mind you, I rather fail to see how crushed X5 headers would magically not create standing waves, while, say, the Ergens do. And why not simply say that the Ergens are kind of a lazy design and could have been done better? It's absolutely true that they are not as good as they could be, both from the crush bend, as well as the cheesy merge perspective. The fact of the matter is that the stock headers have a rather oddball design as well that is virtually guaranteed to create flow issues.

 

[Nick325xiT 5spd]

1) The question is how are these worse than OEM?

2) They made power in direct swap outs on the M60 740s that they were designed for. You know, the ones that came with the same manifold as the S62.

3) Here are some nice pictures of crushed X5 headers:
R3VLimited Forums - View Single Post - Exhaust manifold work

In my opinion, that's unacceptable.

 

[Nick325xiT 5spd]

Actually, upon further looking, that appears to be Genuine BMW OEM crushing. They just come that way.

 

[Nick325xiT 5spd]

The ones on my 4.6is didnt have that dent there when I pulled the exhaust that I recall.

eBay suggests that it's factory.
00 01 02 03 BMW x5 Left Driver Side Exhaust Manifold Pipe Assembly 4 4L 11305 | eBay

Seems to be consistent across all of them that I can find.