NCBob

You are absolutely correct. The Magnuson-Moss act stopped auto companies from voiding the entire car warranty for after-market bolt ons. MB would be hard pressed to prove that headers, air boxes, or other bolt ons actually caused an engine failure.
Merc63...not sure where you got your info, but it is inaccurate.

ShaneN.

Problem is you're probably running a tune if you've got bolt-ons, and I'm sure it's not as hard to void warranty on something going wrong with that done. I've read on here they can't tell it's been tuned if you load the factory warranty but I'm not sure how accurate that is, I'm pretty sure they could see that it was flashed like a couple days before you made a warranty?

Merc63

Ummm no I am not wrong. I took my car into the local dealer (Canada). Lifters were extremely noisy on startup. They wouldn't touch the lifters. Took a video of the car and pics and sent into mb Canada.

They said the car was setup for racing and modified to that extent.

Tune, lowering springs, light weight battery, kn filters, headers with no cats, after market wheels. All these items were logged and I assume the warranty attached to anything modded was void.

You put headers on good luck getting anything done on your engine or tranny. Abother dealer here just got a call fom mb head office for doing warranty work on modified cars and turning a blind eye to the mods. They got in huge poo poo.

You mod your car, you deal with the consequences.

Merc63

They can 100 percent see a tune if they are looking for it and dig.

Merc63

Sorry I should have been more clear.

Of course if you have headers and your nav screen blows up they will probably help you out.

But you put headers and a tune on. Your power train, engine, tranny, exhaust, engine mounts, cooling system, and maybe a few others are void. They will point the finger at the mods as a source or contributing factor and wash their hands of you.

luke22:36

Merc63, Thank you very much! (And everyone else)

I got my long tubes in yesterday, but now I'm not sure whether or not to wait until my warranty expires before I install them.

I know many of you may disagree with my reasoning, but I mainly wanted to get the maximum potential out of my stock engine by letting it breath as best as possible and to make it sound more aggressive without voiding the engine or drivetrain warranty. (Once the warranty expires, all bets are off.)

The first step was to be the exhaust. I wanted to go with the Brabus or Meisterschaft Titanium valve exhausts, but ended up with Brabus non-valve. Next was going to be the air boxes and filters, but after seeing the G55's stock exhaust manifolds, I decided that headers with high flow cats was next step. I was concerned with some comments, that a tune was necessary with headers or a lean condition would occur. I searched elsewhere and found others' experiences and comments that were somewhat what I surmised; That spent gases were spent gases. The headers and high flow exhaust would only facilitate the exiting process with less back pressure and more efficiency and that the computer would automatically adjust for the correct air/fuel ratio. If anything, their engines ran richer, which is fine with me.

The next step would be the intake. Man those CF air boxes are pricey. I know Fabtech has gotten some bad reviews here, but there seem to be an equal amount of good reviews, if not more. There was one 03 SL55 on this site that claimed the ONLY modification he did was the FTP intake; and though the before and after numbers may seem questionable, you cannot deny the difference in what his engine/vehicle sounds like before and after (If what he says is true about that being it's only modification). And it is very reasonably priced. Again, I believe the the factory computer should make the air/fuel ratio adjustments. From my personal experience and aquaitances' (on different brand vehicles) a K&N intake system made the biggest difference on EFI engine mods, more so than any exhaust mod. The only thing that worries me about the FTP intake, is the heat and it possibly voiding the MB warranty.

My other half asked me why do I spend so much on my vehicles, especially the induction and exhaust. I grabbed a straw and started breating through it. I then grabbed a much bigger straw and showed her the difference and told her to imagine being the engine. She then immediately understood when I told her, it's to help the engine breathe easier, in and out.

That's mainly what I'm trying to do right now with an upgraded exhaust, intake and headers with high flow cats, without a tune. I think it should be okay and I think it would be tough for the dealer to prove that these mods caused any engine/drivetrain damage. But I am still uncommitted. If there's anyone that has done these mods before without a tune, I really would like to hear about your results, dealings with the dealership, etc.

Though pulleys will probably make the difference in power, I do not want to change them right now, as this will change the boost pressure and engine dynamics. It will spin other things faster, wear bearings faster and almost certainly void warranties. As for upgrading the throttle body, injectors and fuel rails, maybe after the warranties expire.

Regarding a tune, I'm on the fence. I really would like to do it, as I know it will make a difference, but I'm also sure it could be grounds for voiding warranties. Is it really hideable from the dealer? Some say theirs are, some say the techs will see it. I would definitely want to get a system that can flash back to stock.

I'm a newbie here, but I've been around performance cars and trucks since points were the only type of ignition systems in use, fuel injection systems were mechanical only and Mickey Thompsons Super Scabs were the only scavenger headers on the market.

Any comments, help or criticisms would be greatly appreciated. Thank you in advance.

NCBob

Merc63, you are correct. I did not realize that you live in Canada where the Magnuson-Moss act probably has no influence.

When I bought my C63, I asked the dealer about how they treat tunes. Their response was not to do it unless I wanted a voided engine warranty. Now I am guessing that if I install headers without a tune, I'll never reach the full performance potential of headers.

What I plan on doing is asking if the dealer does engine tunes. I bought my C63 from Rick Hendrick of NASCAR fame. He also owns a Porsche dealer where I had my 996 TT Evo tuned and the warranty remained in full force. If his MB dealer will do the tune, I'm hoping to be covered like my Porsche was.

nrgy

Just thought I'd chime in as I'm running 200 cel cats with my LT headers. I posted a lot about this in the past, along with comparisons with other local C63s running catless setups, and unfortunatley if you are expecting a reduction in sound with the 200 cel cats, you're not going to get much. About all it does is take perhaps some of the rasp out under full throttle...I'd say just a tad more refined. But it's so loud anyway, it's hard to compare.

And yeah, you lose up to 10 hp, but it's really negligible imo. Our trap speeds were all very similar. If I recall we all topped out at the same trap on that day. My ETs sucked though being on street tires.

skaarlaj

Thanks for the info nrgy.

whoadude

hmm if thats the case is there really a point in doing 200 cell cats?

NCBob

The point is being emissions legal. They really frown on tampering with cats here in North Carolina.

whoadude

Can't be worse than in CA. Even with high flow cats we're not emissions legal with the removal of the primaries, which is what I meant by there's really no point.

nrgy

Well, put it this way, after doing some side by side sound comparisons with catless cars at the dyno AND at the track, I went ahead and bought some catless mid pipes. I never did get around to installing them however, and at this stage of the game I don't plan to...but at that time I didn't think the sound reduction from the high flow cats was enough to warrant the hp loss.

One member on here brought a db meter with him to the dyno day, and essentially all our cars were off the charts and out of the range that the meter could measure. Basically when you get to those db levels, I think the human ear has trouble discerning super super loud from super super duper loud lol.

whoadude

nrgy thanks that's great info!

4ramin

Look at the pics on this link , my 3rd pic

https://mbworld.org/forums/c63-amg-w...lling-c63.html

Cats are v banded and take 5 min to change in and out

I use a set of random tech 200 HFC cats for the street ...

Pm me with any questions

CoolBDPhenom03

That's like the setup I had Vivid create for me. It's 5 minutes if everything's fits perfectly. Could be an hour if you have to wrestle with it. The clamps can be a little tricky to get into position so that the threaded end doesn't stick out.

4ramin

That's great, I also added a xpipe that helped with TQ and loudness.

ShaneN.

I'd think so. I asked the same question when warranty was brought up in another thread regarding warranty and a tune and some of the tuners said it can't be detected.