E30 Racing Dynamics Headers

[nando]

yes, see the pic above. mine are from an E34, but either will fit, the E34 just require some "massaging" of the firewall. E30 specific RD headers are pretty hard to find, though.

[ForcedFirebird]

well.. no. they aren't truely equal length. I measured - they're within about 6" (24-30") of each other. But it turns out equal length isn't as important as overall system length, the diameter of the pipes, and finally the design of the collectors and final merge, which are pretty important. from 6" to 1" difference, you won't notice an improvement (people who've actually built & tuned headers will tell you the same thing).

Packaging becomes a serious problem when you try to build truely equal length headers, with no real benefit, and probably drawbacks as you have to introduce extra bends and welds to make it fit. And having some difference may broaden the powerband out a bit. Chasing that 1" difference is not worth it.

the benefit comes from their tuned length, diameter, and decent collectors (pyramid in the middle - no dead spot like ebay headers) as well as overall build quality which is way over anything from China.

The collectors could be improved on (true merges), but to get headers of this build quality with merges like that would cost $2k. And they make them, they're called BTB headers from the UK. ;)

Using the sound waves that reflect off the collector, timing it just right to help evacuate the next pulse is the idea behind tuning the length. Most fabricators try to pick up the third pulse which happens to be about 30" with our bore size.

How did you measure them? I build near-equal-mid length headers for GM 60 degree v6's and the only way you can truly see how close they are is by measuring the volume of the primaries, you will never even get close by measuring them with a tape.

I will be building some long tubes for my m20 e30 soon, using three true merge 2-1 collectors just so see how much can be gained before I build some turbo manifolds.

[MC Hammered]

So what gains are expected from using these headers?

[e30driver]

So what gains are expected from using these headers?

I won't throw out any hp numbers, because I can't back them up with proof. As others have said, the sound is awesome and the look is outstanding. I can say that they are guaranteed to increase the badassedness of your e30 by at least 300 to 400%.

[xwill112x]

nice engine bay sharpie

[ForcedFirebird]

A decent set of headers will usually net about 10% gain, a really good design will gain closer to 15%.

[e30driver]

I found a couple of spare Mahle OC 25 oil filters that I had on the shelf for use with these headers. Same filter as E30 M3. Since they area little shorter, oil changes are easier, and the filter block does not need to be rotated. I'll toss them in the box.

Thanks,
Carl

[nando]

or turn the filter housing 180 degrees, and use the stock M20 filters. :p

[e30driver]

I saw in your pic that it was flipped around. I haven't looked over any ix's very closely, so I thought all of them were like that. Ha ha.

or turn the filter housing 180 degrees, and use the stock M20 filters. :p

[Dagamus(NM)]

Sold to me. I can't wait to get these coated inside and out an put on my white car.