exhaust.... definition of OEM and OEM equivalent?

#1

I cannot run the spec exhaust. I’m not competing anyway but I want to avoid making a decision that keeps me from making the switch.

The current rule reads:

9.3.4.2. Any Spec E30 car that is driven on public highways, to a competition event, must use either the Spec E30 spec exhaust or a fully functioning OEM or OEM equivalent exhaust system that may not be modified in any way.

The exhaust on my car now is rotting and has kept me from passing my local inspection. My question is, what is an “OEM or OEM equivalent exhaust system” as written?

Is it original BMW parts? Is it BavAuto’s el cheapo cat back? Is it IE’s bling bling stainless cat back? Is is whatever 2 in, 2 out system Cooter cobbles together for me at the corner Meineke? eBay special? :stuck_out_tongue:

Seriously though, I need to know. :slight_smile:

#2

I’d interpret that rule to mean that any commercial off the shelf, street legal, OE equivalent, exhaust is okay. That implies that the tubing size, routing, and muffler placement are equivalent to the OE configuration. That also implies that forward section of the exhaust (containing the catalytic converters) is OE or equal and that neither can be modified. So any of the commercial exhausts should be okay, but one made up by the local muffler shop would be questionable.

#3

…duh

3.3. “Original” and “stock” mean “as originally fitted for the chassis, model and year of the car.”

I suppose that means all of the options above may fit the definition except Cooter’s handiwork. Is that a safe interpretation of 9.3.4.2?

If so, I will probably go with one of the boxed packages for some nice long life and a little future resale value.

#4

This rule is really designed to allow those who are driving to the track (very few) an opportunity to legally drive the car on public highways and also race in Spec E30 competition.

The “spirit of the rule” would expect this exhaust to follow the original configuration (bends, number of tubes, size of tubes, functioning cat and muffler, both of the same basic size and shape as stock) of the stock exhaust.

This is also supposed to be a temporary setup until the car becomes a trailered car and thus will need the spec exhaust.

I don’t see there being strict enforcement…unless it becomes a problem, which I doubt will happen.

Clearly, we have seen that exhaust design can have a significant effect (affect?) on performance so we want to see Spec E30 race cars have the spec exhaust as soon as possible.

Carter

#5

Thanks for that clarification, Carter. I really appreciate it. :slight_smile:

And my apologies for the delayed thanks; I had a little surgery last week as part of my whole cancer gauntlet and am just getting back online. Building this car and getting it on track has been a big motivating factor!