4-1 Exhaust Headers for M42 on Ebay

[futron.sim]

http://cgi.ebay.com/ebaymotors/BMW-E36-318is-318ti-92-99-Exhaust-Header-Headers_W0QQcmdZViewItemQQcategoryZ33631QQihZ017QQitemZ270235170589QQrdZ1QQsspagenameZWDVW

I seen these headers on ebay. Is anyone using them? Any noticeable increase in power compared to the stock headers?

Thanks!

[Ruger]

Ive seen these also. the design is near identical to stock except a 4-1 collector rather than 4-2-1. Even spoke to the engineer about it (good mate) and he reckons its a waste of time. All it will do is move your powerband up and make it a pig down low. If the primarys are larger also it will exxagerate that effect.
If building a fairly modded m42 (180ish hp) id consider it but otherwise it will probably do more harm than good. Power increase on a fairly stock engine? id say 5hp but youd want to be revving it to 7200rpm at least to get that 5hp out of it.

Another thing to consider since its from the states is will it fit a RHD car since the yanks dont have a steering column down there it might not fit our cars.

My 2c.

[peerless]

Have your header ceramic coated.

My customer just had his coated at a local company called Embee Coatings.

Here is a blurb about their header coating:

The Ceramic Exhaust Coatings are for headers and exhaust systems. They are available in seven colors (polished silver, matte silver, satin black, titanium, gray metallic, blue and white). Our exhaust coatings will increase the efficiency of your engine by increasing your exhaust velocity and improving airflow, resulting in reduced under hood temp- eratures. Guaranteed not to blue, stain or rust, our exhaust coatings provide superior protection for your new and used components.

We chose the 'Satin Black' for our 'Bumble Bee' color theme.

[mkodama]

Ahh, that seller, delubozparts, I've seen him around.  

He also sells headers for the E46 3 series and they make a pretty big difference on the E46.  The E46 came with a pretty crappy stamped exhaust manifold with built-in catalytic converters.  Switching to the tubular headers sold by delubozparts resulted in a 15hp gain on a 330i.  The headers sold by delubozparts reportedly fit well and were of good quality.  Only downside was that the large diameter piping created a loss of torque at low RPM's.

But stock headers on an M42 are already really nice as shown by the pictures Peerless posted.  My guess is that the difference would probably be pretty small.  But for the price, a great option if your OEM headers are damaged.

[Letsplayskatch]

I know i posted it before but:

http://www.cdfracing.co.uk/product_info.php?products_id=185&osCsid=018bfb759f63985a6256a851d4be4fb7

Im unsure of stock diameters versus these CDF ones, but they 'seem' decent, all TiG welded and mandrel bent. The runners look slightly larger then stock too, and the 2-1 collector is cleaner than stock.

[Cobra Jet]

As others have stated, the stock M42 factory designed tubular header is EXTREMELY NICE when comparing it to other vehicle header(s), as some other manufacturer's designs are restrictive and often "pinched" in the curves and not mandrel bent.

The M42 headers are really unobtrusive and is a VERY WELL designed piece that allows ample exhaust flow w/o any real restrictions.  IMO, I just think that spending $$$ on the aftermarket header for any M42 would be wasted when the $$$ can be put towards other more potential mods that would net better gains.