NitrogenBalance

So I got the SS y-pipe, metal cats, and 3in stainless welded up last week. The car sounds great with the stock muffler and no resonator. The only issues to fix are that I still have the 2.5in muffler feeding off the 3in pipe which defeats the point of 3in pipe. I have a 3in SS magnaflow but didn't have it welded up because the shop couldn't do mandrel bends. It was only $25 more to have the entire rear section made 3in so I said go ahead with the crimp bends for now. I've ordered the mandrel bends separtly so once they get here I will have the rear bends welded up with the 3in muffler. With the 2.5in bottle neck and the crimp bends I really can't say the car is any more powerful. Once finished properly I think it will be noticable.

....also odered the sprint booster today. It should make the car funny to drive as its all low end grunt now anyway.

Ashkan's C43

by metal cats I would assume you mean the brand metal cats right? You did not see any gains from using metal cats vs stockies? Did you replace primary cats and get rid of secondary, or get rid of primary and replace secondary with the highflow metal cats? Did you get 200 cell each or 100 cell each? Did you get any codes? Any reason you went with a y pipe vs X or H? How does the sound compare with stock since cats have been changed?

NitrogenBalance

Wooww Nelly,

200cel metal cats, stainless. I the O2's feed off the primarys I believe therefore it doesn't effect sensors. Kept the primarys because prodjectC55's posts make me need headers. The headers will delete the primarys so I'll need to relocate O2's and keep secondaries. Y-pipe because the exhaust is a 2 into one design and trying to do custom duals all the way back isn't something I wanted to do as it would still be single exit and I'm not sure it's that much better than single 3in. Sound is great. Performance should be seen once I repalce the bends with mandrel and get the 3in muffler on. whpeeuuu that was alot.

MarcusF

Where did you buy the cats and what brand? Which supplier did you use for the mandrel bent tubing? Thanks

ProjectC55

You mean to tell me that you noticed no difference in the way the car now performs?

That short 2.75 inch section is not gonna make a very noticeable diff Nitr. Went to my high perf exhaust fabricator last Wed and these were actually his wrds as I wanted to chg that lil section as well. So I'm leaving it. It's also bigger than 2.5 inch almost 2.75 inches. However your system now looks exactly like my exhaust minus the headers and down pipe. ,good job.

You should have definitely noticed a difference bottom end,midrange and topend. If not,allow the ECU time to adjust and give the car some spirited runs. I had to do this with the header install where I was extremely dissappointed at first ,then after driving the car a few days I am completely in love with the headers now as the car has adjusted and really feels like a beast. I had some runs against Jody's modded W211 E55(SLR cams,pulleys,kleeman headers). He did kill me upstairs but he was amazed at how from a roll the car would be right there until it got to the higher rpm's in 2nd gear. After that it was all over for me. Rape-age!

Never the less my car runs very good. Let her adjust then come back to us and keepus posted. I had to take Speedy Benz's advice with this.

ProjectC55

can be found on E-bay(Mandrel bends). Google Metal-cats and you should get a link.

NitrogenBalance

I'm very pleased, especially because of the sound. I'm thinking that the wrinkle type bends are what negate the performance? I have to get 3in mandrel bends now anyway because my rear section is history. I mean I defenitly didn't loose any performance, I just couldn't tell you a +/- 5-10hp difference in my car at this point.

I'm looking foward to having the 3in mandrel and 3in SS exhaust welded up to see if it's really the crimp bends and AMG muffler.

ProjectC55

Doubt it but then again you have no clear pics of the whole system.

E55 PWR

Hi Nitrogen,

Not a bad first attempt but there are a few things you can improve upon. First off, mandrel bent is key but you already know that. One key thing I would have done different is use a Flowmaster Y-pipe versus the Magnaflow. The Flowmaster Y-pipe is much more free flowing than the magnaflow design. In order to properly design an exhaust system for the C36 you need to scrap the entire stock system. The stock muffler is extremely restrictive and is really only a 2.25" muffler so thats your biggest problem.

The best possible system is as follows...
- Do Y-pipe on the two header downtubes before it reaches the under body (use flowmaster dual 2.25>3.0" y-pipe. This will also make the entire system a single pipe 3.0" system which will also maximize weight reduction as well)
- Use 3.0" down tube w/ a mandrel S-bend to the center section.
- Run a 3.0" metalic high flow cat
- run a 3.0" 22" long magnaflow resonator for highest quality sound
- another set of 3.0" mandrel S-bends to rear section
- 14" 5x8 magnaflow muffler or if you want aggressive sound, get a 14" long 5" diameter 3.0" resonator and use it as a muffler (its a round body).
- Magnaflow makes a set of oversided AMG looking tips for the 3.0" diameters so you could get those (most of their tips are only 2.25" inlets).

Thats basically as free flowing as an exhaust system will ever be able to get for a C36. Ditch the stock system and sell it for $$$ and you can recoup most of the cost of the new system. hope that helps.

E55 PWR

Here are some pics to help you guys out...

Flowmaster - Y-pipe.......


Inside of the flowmaster Y........


Resonator...


Muffler...


Tips (3.0" inlet and very similar to AMG tips)...



Hope that helps anyone trying to design a super high flow system for the C36. If that doesn't make power on a C36 then nothing will (it should make good power if done properly). The whole system should cost under $750. hope that helps.

ProjectC55

Omey! He does not own a C36! You have a good idea there but the problem with the "flowmaster Y pipe" which I did purchase first is that it will rust because it is not stainless steel. That's why I went with the "Magnaflow Y". I personally would rather be consistent with what AMG has and keep the system stainless steel. That's my personnal taste because it's an MB.

I can tell you that it certainly has not hurt the performance of my car.

E55 PWR

I know just putting my input in . Are you sure the flow master is not stainless? if so then that could be an issue. I used it on my BMW racer and never had any issues with it and it performed great. I just don't think the magnaflow Y is the most free flowing but i guess its better than nothing. anyways my 2 cents .

ProjectC55

I'm 100% sure. That's why I sent it back even though it's design was somewhat better flow wise. The magnaflow Y pipe is not gonna have any major negative effect hp and flow wise.

E55 PWR

but the inlets are so far appart which is annoying. Oh well ya, either or whichever you prefer. I think a full single 3.0" pipe system is a much better route to go IF the exhaust shop will let you. some are **** about converting from dual cats to a single one so it may require some persuasion on your part. Weight wise its much better and its also much simpler. Downside is fewer components work with 3.0" setup (harder to find tips, you need larger outter diameter resonator and etc). you could probably shed a good 20-30 lbs out of the exhaust system depending on what setup you go. Anyway good points guys.

ProjectC55

Worked good for me because I was able to put the cats in thier original position without them hitting each other. Also since I have Kleemann headers and Kleeman downpipes,no primary cats so my system is light already! Your not gonna lose much weight making the exh 3" further up towads the front of the car. Where would you place the y pipe to lose a whole 20lbs?

NitrogenBalance

I also don't think you could weld up the metal cats to the flowmaster y-pipe nicely because they are too wide. Welded up to the magnaflow they only have about a couple mm between them. Burns stainless makes a nice Y pipe desigen which is proabably the best considering their reputation. I also thinks it's something silly like $90 or so....

Thanks for the thoughts Omey.

E55Cent

Great job, Wes!
Hey Carl I hope you are well, I would agree with Wes that he felt nothing but he most likely did gain power. The problem is his car and my car are running so much more TQ and HP than an N/A Benz that even when I added 35whp to my car with methanol/h20, I barely could feel it. The problem with power is the more you have, then the more you need to feel a little bit.
Mario

ProjectC55

Exactly!!

ProjectC55

I can understand that!

DarthCY

I like the idea of the water/methanol on an NA. Really want to do it to my 951 as well. How do you like it? Did you have problems tuning it. I've been considering doing this, but an Aquamist is like $500. The cooling mist looks more affordable. Don't need it, but steam cleaning the engine and bumping up the octane is cool.

Don't want to thread jack, sorry. Not really into modding the C43 now, but in a few years I'm thinking that a chip, UDP, plugs, filter and this exhaust mod would make for a nicely running car.

E55Cent

I'm not sure many people are using CoolingMist on an N/A motor. I'm not sure it will help that much becaue your car isn't running hot or do you have detenation problems. If you want to raise the octance I would just put in two gallons of race fuel for every tank of gas.
I have also done the UDP, plugs, filter, exhaust and Powerchip. All of it was crap and gave me nothing. The only things that make power are cams, headers, supercharger and cats. Once you have these then software can make a difference.
Mario

suicidal4life

I guess great minds think alike
I returned from a weeklong trip yesterday and discovered UPS had delivered two of these.

NitrogenBalance

Tryin' to figure out which mandrels I need now as far as angles go....

...and Carl, the car has seemed a tiny bit more responsive lately

ProjectC55

OT. MARIO!!! Whattup! What did you think bout the pullies when you were N/A? When do the headers and exh go on in your application?

PS I can't imagine you being 6ft 2" tall and driving a 400hp Mini!

ProjectC55

Give it some more driving time. you'll see as I'm finding out with my car and enjoying it more and more and more. Next is to go for some ne rear tires for the 1/4 mile.