On my E500 I had Eurocharged mid-lengths installed and have been very happy with the hp gains and modest noise increase. Lost my primary cats, but kept the secondaries and replaced the resonator with an x-pipe.

 

 

You have to use it and lose your primaries.

 

 

 

I know Renntech does but they're ridiculously expensive.
Why not just go mid-length and lose your primaries?

 

Shorties are a waste of time I am afraid. The goal is to eliminate the tiny header to cat connection of the stock setup. This is the real restriction. I don't know how it works in California but I would either stay stock or try and use eurocharged headers with an aftermarket cat welded underneath.

 

Here in wonderful California you have to have primary cats or you won't pass smog. It's also a very expensive fine if you get stopped by the police for not having cats.

There are no aftermarket cats that I know of that are CARB/EPA certified. Aftermarket cats are pretty much as illegal as not running any at all here. Just removing the cats can get you in a lot of trouble and most shops won't do it.

I hate this ****ing state and can't wait to get the **** out.

 

 

I would just leave it be. Headers aren't always problem free even in normal situations.

 

If I were you, I would get PLM headers (similar to renntech, if not an exact copy, but a lot cheaper). They are direct bolt on with no changes to the rest of the exhaust system (cats, etc). You can find them on ebay. I think the seller usually offers a significant discount compared to the listing price if you PM him and ask. They're not quite as good as long tubes, but several (supposedly un-biased) forum members have posted impressive dyno results (IIRC, something like 30-40 whp).

 

30-40whp would be longtube territory. You will increase torque but I wouldn't expect much on the top end.

Different engine but the C32 crowd would be lucky to get 5whp with shorties.

 

Move to Mississippi. Everything else here is $h1t but there is no such thing as DEQ. They don't even look at your car when you register. Just walk into the court house, pay some money, leave with tags. If you could find a way to power your vehicle with sulfuric acid no one would bat an eye.

And if we are keeping score:
Mississippi = 1 California = 2,894,235,102

 

I have Kleemann header and they are mid. Your ECU need to re-program so will not show check engine light (removing Primary CAT)
The only issue is visual inspection otherwise you should pass any Smog check. I have my header for 7 years and bring good power and sound.
Don't waste you money in shorties... they don't bring much power.... Renntech used to sell $2K for those shorties...

 

According to the dyno numbers posted by some forum members a few years ago, the gain is 30-40 with shorties, but it's entirely possible that the results are inaccurate or biased (both people claim to be unbiased, but I suppose everyone is at least a little biased when it comes to their car). I believe one person reported mid 30s and the other person reported just over 40. I don't remember specifics, but I think at least one of them was un-tuned (before and after) and at least some of his gains were from leaning out the afr. With a tune before and after, the gains probably would have been less.

I know everyone swears by long tubes, but has anyone actually done dyno testing to see what the difference actually is (not counting the claims of manufacturers)? Has anyone dyno'd shorties vs stock and not had good numbers?

You can't really compare with a C32, the manifolds are a lot more restrictive for the E55 (same design, but much higher power output in the E55 means the manifolds are holding it back more). The gains should be much more on an E55 than a C32.

No doubt long tubes are better, but if you can't have long tubes, I think shorties are well worth the money.

 

There are plenty of dynos from people running long tubes and those running mid length to get an overall impression of the differences. I'm not saying I'm correct by any means it just doesn't sound realistic for shorties.

The other way to think about the C32 comparison is that if the stock header to cat join was so restrictive that it didn't result in any increase in power.... the effect must be at least as bad on the E55 if not much worse.

Not many people are objective about their mods. Again not the E55 but when I got a tune for the CLK55 from eurocharged I would be surprised if it gave 4hp. It did give a whole heap of mid range torque but no one ever mentioned that, all the fixation was on trying to prove it gave an extra 20-30hp to the top end which it didn't. When someone finally did a back to back dyno you could hardly see the difference in the lines near redline.

 

I am pretty sure California switched over to just visual smog checks without the tail pipe test. As long as your OBDII isn't throwing codes you should be fine.

https://www.bar.ca.gov/Consumer/New_...heck_Test.html

 

I don't remember the last time I had a car go on the rollers here. If they see missing or non-OEM cats you may be ****ed.

 

Last few smog checks they don't even look under the car. Only in the engine bay.

 

We have one last set of midlenghts in stock