rbaker

How many people would be interested in headers and/or full custom exhaust for their C55's that doesn't cost a million bucks? I was at my local race parts fabricator today (he mostly does Porsche) & we started talking about the ridiculous prices for RENNtech headers & such, and he offerred to use my car as a guinea pig to build some custom headers & maybe a full exhaust if there was enough interest. Might even combine this with a canned dyno tune to optimize this setup.

His biggest questions are if there's enough interest to warrant development, and what customer preference would be for the setup:
1) Would people prefer a shorty header that bolts to the factory CAT for simplicity (like RENNtech does), or a med/long tube for max power? The difference is huge, but remember some have smog...
2) If a long tube header, consider that it would be pretty much mandatory to buy the rest of the exhaust, from custom CAT's, pipes & mufflers all the way to tips.
3) With a shorty, the header back (or cat back) part of the exhaust could be optional/separate.
4) 304 Stainless or ceramic coated mild steel headers?

Give me your input and if there's enough interest I can get him to cook something up. As for pricing, all I know so far is he thinks headers could run between $1500-2k depending on material, short/long, etc. This is much more affordable than what I've seen out there and would perform equal or better than what's out there now.

ProjectC55

#2

Eurocharged Rick

without proper tuning, long tubes and full exhaust would be a waste of money...you will actually lose power because the ECU cannot compensate for that much added flow...

even with shortys, you should still have the ECU retuned to take full advantage of the change...

Tump43

I'll go for shorty's if my renntech deal does not go through.

rbaker

That's why I said a canned dyno tune could be offerred based on the guinea pig car. It's mainly for the folks that don't have the resources or want to do their own dyno tune. And yes, with a long tube design its a must. On shorty headers like the RENNtech it's probably debatable how much change is needed as the factory tune already runs slightly rich on these cars.

It's all going to boil down to how much interest there is. If there's only 2-3 people wanting to do it, I'm not going to let my car be used as the guinea pig for weeks when it's doubtful the shop would want to touch it anyway to sell only a couple sets. Then they'd have to charge me a ton for all the development work to make anything...

jordanst2

If shorty's were also applicaple to w210 e55's i would be very interested, pending a reasonable price and a viable tuning solution.

ashura

id be interested in a set of shorty's

rbaker

Sorry, but the W210's use a different exhaust manifold.

Near as I can tell (by comparing MBZ P/N's), shorty exhaust manifolds/headers that fit a C55 should also fit the CLK55/500, SLK55, and may fit _some_ SL55's (I can find 2 different right side exh P/N's for the SL).

Of course the long tubes may be different, and the full exhaust would be C55 only.

rbaker

So looks like the current tally is:

1 vote for Long Tube Headers (and therefore a full exh)
2 votes for Shortys (that bolt to the stock exh)

Let's see if anyone else comes forward in the comin days/weeks as this isn't enough units to put in the development time.

I'm heading out on a business trip from the 3rd to 10th of Sept, so I'll tally votes when I return & talk to the shop then.
--
Roger

RawAMGpower

rbaker, the problem with long tube headers pure and simple is that you will not pass smog with them in CA. I see your in LA so that option you shouldn't even be considering. Yeah longs look cooler and add more power, but in CA they just won't fly. Unless you want to swap the setup out before you go in for smog.

Anyway, I already have the renntech headers, but if you make a full exhaust that can bolt on to them or a exhaust from the secondary CATs back I'd be interested in that.

Oh one last thing if you get shorty headers programing is a must. My ECU got reflashed one time at the dealership to factory stock with out me knowing and my car felt like it was running slower after I picked it. So I decided to have it dyno'd and sure enough it was running lean with the stock program and I was losing major hp. Once I got it flashed back with the renntech programing it was fine.

rbaker

1) Smog is obvious... but for some, smog is not an issue... the options remain open for those lucky people!

2) I have RENNtech's on now with a custom exhaust. They're not what I call super impressive, but do help some. I'll put your vote in for the header back exhaust.

3) Hmm, strange, my car seemed to run fine & be quicker up top even with the stock programming... I'll have to do some measurements to check it out, but my C55 definitely ran RICH stock!
--
Roger

spr

first off the ecu will adapt for the increased flow- that's why there are o2 sensors!

Second an equal length shorty style header in stainless steel is ideal with special attention to the collector design and how the finish of the primaries are melded together. A firecone design is very nice in this regard if welded correctly.

Once is jig is made they could be made and sold for a reasonble price of 500 I would guess and ceramic coated for a hundred or so more inclusive of R&D fab design. Anything over that is pie.

rbaker

Um, ya, obviously... At least within the limits programmed into the ECU's scalar adaptation tables. Although there are actually 4 o2 sensors, and the second ones after the CATs are just there for checking proper CAT function.


Yep, a true merge collector works much better than just a "pipe dump". I don't know if I'd call a shorty "ideal", but it can work pretty well. Especially if proper attention is paid to pipe diameter, length, and any resonant tubes to adjust the timing of the reflected sound waves. I have a couple ideas that could really help this, but unfortunately it wouldn't look stock at all, and I'd like to keep shorty headers looking rather stock.


Ya, but remember the cost of that jig and all the time testing, tuning etc., needs to be amortized back into how many units are sold! If only 3-4 units are sold... well you can guess the rest.

spr

good point on the issue of demand. Sounds like all the right things will be done. If you post some dyno numbers from the c32 stuff you did or better yet a dyno run off your prototype then you can get your demand estimates and fix a better price point to surpass even initial demand etc. Sounds good. Any pics of the c32 ones you did?

AMGSC

I am waiting for Vadim@GMG Racing to give me quote but am VERY interested in a header/exhaust kit along with throttle body/intake upgrade.

alroumi

I dont mind getting shorty headers as long as they fit my SLK, count me in.

RawAMGpower

A throttle body/intake upgrade would be something I'd be interested in too, but only if it adds at least 25hp to the wheels.

What pulleys do you have on your car?

ProjectC55

The C55 exh mani's would perhaps be more similar to the exh mani's on the C43 and W208 CLK55 which are pretty much the same exact parts. Everything else on these two older models exh wise would be entirely different to the C55.
The W209 Clk55 is similar to the C55 from the exh mani's up to only the cats. After that you have a single exh setup on the W209 CLK55 vs a dual exh setup on the C55.

c55asleep?

hello i am new and want to say greetings to everyone. i was just curious
if i have renntech ecu and airbox and were to add those shorty headers would
i have to reflash??thank you.

RawAMGpower

Well, yes because renntech's program is different if you have their headers, but it won't make that much of a difference if you don't reflash. However, renntech will do it for free.

c55asleep?

thank you for the info. i guess if they do make the shortys i'm in. i will have
to talk to Bob at renntech.

AMGSC

If you are interested in a compete throttle body/intake upgrade for a C55 then please PM me. I am about to purchase such a kit from who designed, tested and successfully mass produced these kits for our cars. He also designed a larger Heat Exchanger for the blown C55's and phenolic spacers.

Combined with the lightend crank shaft pully, smaller underdrive pulley, Kleemann Headers, Cams, Cats, ECU and Eiseman exhaust and the new Eaton TVS blower, I should finally have a completely proven and sound system by the end of October. I see the Johnson Pump CM30 is a very popular replacement for the Bosch intercooler pump but I plan on using the CM90 also.

E55 PWR

Shorty, Stainless headers are the best for simiplicity & fitment. You can still get good power out of the shorties, yes long tubes will technically make more power but at huge cost (both time & money, as well as headaches).

MRAMG1

QUOTE=E55 PWR;2413062]Shorty, Stainless headers are the best for simiplicity & fitment. You can still get good power out of the shorties, yes long tubes will technically make more power but at huge cost (both time & money, as well as headaches).[/QUOTE]

Here, Here

I made just alittle over 500hp out of 5.0 mustang with shorties. Long tubes would have required relocated 02's, and as you said, MONEY/TIME/HEADACHES

Shorties work great, and are easy on EVERYTHING

See yeah

rbaker

So looks like the new tally is:

1 vote for Long Tube Headers (and therefore a full exh)
4-5 votes for Shortys (that bolt to the stock exh or stock replacement)
And a couple votes for a cat back exh.

I talked to the shop & it seems that 5 commitments would be the minimum number that would get them interested in undertaking a custom header project. At this point, they suggested we consider building them from mild steel & do a ceramic coating but I'm not sure how many people would like the thought of a non-stainless header, even though with a good coating they'd last & have improved heat containment. How many of you guys that are interested have a preference in material?

I'm going to have to take another business trip (China this time) so I'll be out another week. I might drop my car off at the fabricator before I go, to finish up some mods to the CAT back. I'll talk to them about the project again.
--
Roger