Beware of CXRacing (ebay) headers

[Mossman]

I'd grind the mount

[rcfanatic]

I'd have to remove the eta exhaust manifolds (for a third time) to get the header in there and take the pics. I wouldn't mind as much but I'm trying to clean up my hands before my interview on Friday (sounds silly, but whatever). I can shoot a pic of the motor mount though and circle the area where it strikes, if that helps.

[bataangpinoy]

take pictures please.

[StereoInstaller1]

Although I guess with long tubes the pressure wave that bounces back from the collector will take more time to reach the cylinder head, which would match better for torque at low engine speeds. Hmm.

No, the reflective pressure wave is nowhere near the point, nowhere near as much effect as resonant frequency is. Longer tubes, lower Fs, better low end, period.

Actually it isn't even so much as "better torque" as it is that the powerband shifts down towards the bottom end.

[KennyT]

You could make your own motor mount out of steel that would clear.

[rcfanatic]

Although I guess with long tubes the pressure wave that bounces back from the collector will take more time to reach the cylinder head, which would match better for torque at low engine speeds. Hmm.

[MaksV]

A few weeks ago I purchased headers from CXRacing (cxracing.com) off of ebay for $158 shipped. I had to spend $106 when I first got them to have the flange that mates to the cylinder head planed at a local machine shop. It was warped pretty bad.

So I finally finished my 327i project, get the new head installed and go to put on the headers, only to find out they don't clear the engine mount (supporting bracket). OK. I've read about fitment issues before. I take them to the most reputable exhaust shop in town and I'm told that because they are so far out of spec, it would ruin the headers to try and modify them to fit.

Call CXRacing.com and am told that I can send them back, but they won't pay for my shipping costs, which were $55 to receive the headers and probably the same to send them back. They would only refund the $103 which is what they were listed as on ebay.

So it appears I'm out $264. As the saying goes, you pay for what you get.

How horrible of an idea is it to take some material out of the motor mount bracket? It looks to be pretty strong and I think I would only need to remove about a quarter of an inch in a small area.


Edit: The part I'm talking about modifying is PN 11811128496

grinding motor mounts is ALWAYS a bad idea. They are integral - they hold up your engine.

[rcfanatic]

err, you have it backwards - longer tubes give you more bottom end torque, not less. the shorter the primaries, the higher up in the RPM band the torque curve moves.

Really? It always made sense to me that longer tubes would facilitate higher velocity/higher rpm torque

[nando]

err, you have it backwards - longer tubes give you more bottom end torque, not less. the shorter the primaries, the higher up in the RPM band the torque curve moves.

[rcfanatic]

Yeah it's hard to say. I could fabricate some kind of heat shield, or a heat sink to attach to the header, but who knows how long that could take.

I really liked these headers because of their medium length. I feel like the long tubes will eat up my bottom end torque and possible hang too low.

[nando]

the thing is if it's that close to the motor mount, the motor mount is going to get hot. It's not going to last nearly as long as it should.

[StereoInstaller1]

1/4" off a motor mount might be nothing...I don't know if I would be OK doing it though.

Pics of issue?

[rcfanatic]

LOL.. well it's a dog-eat-dog world.

[nando]

I meant sell them to somebody else with a 325i. They're going to buy them anyway (despite the warnings), why not get a set that will sit flush to the head?

basically let somebody else hack up their motor mount.

[rcfanatic]

I knew they weren't high quality, and I knew about the fitment issues, but I just hadn't heard of a case where they couldn't be made to fit *at all*

How could I flip them? What other straight 6 might they fit on?