SRQLAW

I have been looking at variuos ECU/Pulley kits for my 55 and wanted some opinons. Are there significant differences between the various tuners? Has anyone had any particularly good (or bad) experiences with any specific tuner?

Thanks,
D-

BeltFedBob

I went with Kleemann and had great luck. That being said, keep it stock unless you are prepared to do the full Monte. Mods to the SL55 is like a crack pipe, you won't be able to put it down.

I started with a Resonator delete, then pully and ECU tune, then 80mm throttle body, then headers and hi-flow cats. Now i need a Wavetrack because the little yellow triangle keeps going on.

Good luck!

cal1

Having Renntech, EvoSport and VRP mods on my car, I think there are a number of reputable performance companies out there. What I believe to be of paramount importance is who does the install. The mods from all three companies worked as advertised. Getting them installed correctly was a whole other story.

By the way, I have only heard good things about Kleemann.

320 dreamer

we have a dyno tuning session going in atlanta on 12/12 by tony from eurocharged. a master ot tuning the s/c cars. if your in the area theres one opening left. check out the threads on here with members and how they liked his work. better than the big names and cheaper also

https://mbworld.org/forums/sl55-amg-...uning-day.html

SRQLAW

Thanks. The mods will be done by MB Sarasota. They are more than willing to do pretty much anything. Obviously, they want me to buy the parts thru them... but they will stand behind the mods. Also, my neighbor is actually one of the techs there and he and I have been talking pretty extensively about the mods. He has done a number of Renntech packages on both 55 and the 63 with really good results. Interestingly, he was not as excited about the additional mod options (headers, TB, etc - unless you do ALL of them...). It was his experience that the cost pr HP and the seat-of the pants dyno do not really justify it.

cal1

Having the dealer do the mods might cost a bit more, but to me is well worth it. Some MB dealers refuse to do mods like the one here in Indy. The funny thing is, they are willing to fix botched mod installs like I had when a supposedly knowledgeable local installer screwed up the Renntech Package Plus mod on my car.

It sounds like you are in good hands with your neighbor.

BeltFedBob

Here's something to think about. What goes in has to go out and the stock header/primary cats are a big block to the flow of exhaust. The most profound improvement will be starting on the bottom first. JMHO

U.S. Quarter used for size reference;
Header inlet


Header outlet


Cat inlet


Cat outlet

Nebster

eurocharged for sure. I've had tony tune my last car and he'll be def tuning my new car once i pick it up.

320 dreamer

if you had a n/a engine i would agree completely. but the f/i engines get less gains from exhaust mods due to not needing the scavenging effect of the exhaust.
most tuners will tell you to do the exhaust mods last after all tuning and add on mods are done. the especially applies to the s/c v-8 engines due to the high cost of the headers. res delete cat delete will increase sound but do little to inc. hp. shortys work well in conjunction with the deletes but longtubes are the only way to get any significant hp gains in exhaust work

BeltFedBob

Think of it this way:

If you have a stock log type exhaust manifold, with a close coupled cat, with a dual cat exhaust system, small exhaust tubing, and a couple of restrictive mufflers on your car then it is possible at peak power to have up to 10psi of back pressure.

If this is the case, first recommendation would be to upgrade to a high flow, low pressure exhaust system because of the potential power gains; however, where exhaust upgrades are not an option, then you must select your camshafts, and tune your cam timing to where you have ABSOLUTELY the minimum possible amount of overlap. If you have significant overlap, then the more you rise above about 4500 rpms the more your supercharger will suffer and the more power you will waste. If the supercharger is geared to 7psi of boost for example, then during overlap, the cylinder sees 7psi of boost on the intake side, and 10psi of back pressure on the exhaust side, the net result is that air will flow from the high pressure zone (the exhaust) to the lower pressure zone (the intake) and so your cylinder will start to fill with exhaust gases. As the rotation continues, the exhaust valve will close and overlap will end, and the intake valve will stay open for the remainder of the intake stroke (for the rest of the duration of your intake cam), and the rest of the cylinder will fill with fresh air.

What happens here is that we get a cylinder that filled for 30* of overlap with exhaust air, and then filled for another 210* (of the original 240* of duration for a typical street cam) with fresh air. The result is a cylinder that is only 85% filled with fresh air or an engine that is literally 15% smaller in displacement! On the other hand, if our supercharger is geared for 18psi for example, then during overlap we will have 18psi on the intake side and our exhaust back pressure of 10psi on the exhaust side, the net result of this overlap is that our supercharger is effectively only producing 8psi worth of differential pressure between the intake and the cylinder and so we are only going to get a power boost of 8psi during overlap. So, during those 30* of overlap the supercharger is only effectively producing 8psi of boost, and after that once the exhaust valve closes, the supercharger will be able to go back to operating at full boost for the other 210*. The net result is something like 16psi of boost so 2psi (or about 12%) of our power was wasted.

Sunir

Bob that's a very compelling and scientific explaination, however I've heard what guys say similar to what 320 dreamer is saying. I'm trying to learn more about how to setup the exhaust system on the 55K cars as well.. I've heard about how SC cars may not need the wider (like 3 or 3.5" tubing) on the exhaust because opening up that wide may hinder the torque curve...then on the other hand I've heard the arguement that opening up and free flow is always the best...so I'm subscribed to learn more about this...

IngenereAMG

You might want to take a look at our testimonials page. The SL55 (and the 55K) is particularly near and dear to our hearts!

http://www.veloceperformance.com/testimonial.htm

BeltFedBob

I think 320 has it backwards..

"if you had a n/a engine i would agree completely. but the f/i engines get less gains from exhaust mods due to not needing the scavenging effect of the exhaust.
most tuners will tell you to do the exhaust mods last after all tuning and add on mods are done. the especially applies to the s/c v-8 engines due to the high cost of the headers. res delete cat delete will increase sound but do little to inc. hp. shortys work well in conjunction with the deletes but longtubes are the only way to get any significant hp gains in exhaust work"

I have worked on many naturally aspirated engines and exhaust scavenging plays a big part in the performance and economy of that type engine. Just because it's louder doesn't mean it's faster.

Forced induction is another animal, be it turbo-normalized, turbo supercharged, mechanical supercharged and power recovery turbines. The later being the most fun to work on…adding turbochargers to a supercharged engine is a hoot. The key is to get rid of the exhaust pressure as economically and as ecologically friendly as possible. Look at all the big supercharged engines and you will find short stacks or very large diameter stacks to direct the exhaust flow up or out.

They say not much can be done to improve the stock SL55 exhaust system, I disagree. On the next SL55 you have the chance to experiment on it would be fun to dyno with the stock exhaust. Pull the front O2 sensor and check the exhaust backpressure. Next take the "H" pipe, fit hi-flow cats and replace the pipe from the flange with 3" tube back aft of where the pipe is flattened. Check the backpressure again. Finally swap out the stock headers with tube headers and try the same test again. I would love to see what numbers you get, bet each step would see lower backpressure and higher HP/TQ. I don't think going past 3" will gain much change.

On My SL55 I noticed a big difference between the stock exhaust, having the resonators removed then the headers w/ hi-flow cats with the pipe opened up from the flange of the headers to the point where the pipe becomes round again by the tranny.

320 dreamer

on the s/c engines headers will show a gain. the issue is at what cost? dont headers for your s/c v8 run approx 3500 to 5000$? for a gain of about 15 to 17 hp? the sl55 forum is full of guys who have res delete sec. cat deletes muffler deltes. none have shown any decent gains unless headers are added. its more of a sound level folks are looking for.
the same holds true for my 3.2 s/c v6. the srt-6 guys have tried every mod known for the exhaust and the results are minimal at best.
the consensus among most tuners are to do all your engine mods first tune then as alast attempt to get any more power to be had , exhaust.

did you perform any dyno tests on yours before and after or you using the butt dyno for the big difference?

BeltFedBob

320,
The headers are $1495 and cats were $380.
No dyno shops close to me so I didn't get any numbers. Butt dyno and a timer is about the best I can do. The yellow triangle did not come on like it does now with part throttle off the line ;-)

320 dreamer

i got the same results with my c3 pulley install. low end torque off the wall. but wont know the real numbers until i redyno.
you may be correct with your theory. im just going on what the guys that build the cool stuff for my engine and what is posted here seemed to find out.
call the pros at eurocharged. they are modding everything from a slk32 to the sl600 sl63 sl65 ,55 c 63's you name it. they can tell you more than i know. super guys very willing to chat

kamilclk430

I will be pulling the trigger really soon on doing major work for my SL55 including, heat exchanger, pulley, headers, cams, heads, 80mm tb, ecu tune, and so on. Eurocharged for sure is the tuner I will go with, and not because they are in the area but because they are great with customer service and never heard one negative about the quality of their work.

BeltFedBob

Good luck with the mods!
You will not believe how your car will perform after it's done.

kamilclk430

Do you have the same things done?

BeltFedBob

I have Kleemann headers, hi-flow cats and resonator delete on the bottom. 80mm throttle body, green filters, Kleemann pulley and ECU tune to move more air and fuel. Johnson pump to move the coolant. I live in a place that has 60F avg temps so heat soak is not as big of a problem as those in the south.

In my case the pulley and tune made a big change in how the car ran, the exhaust mods doubled the effect.

Not interested in going with cams or head work at this time, the power I have now is more than I can use right now.

Sunir

that's quite a list there Kamil...what kind of head work are you looking at? what kind of cams do you have? Is Eurocharged doing the heat exchanger for you; i;e trunk mounted remote reservoir setup? or simply the dual pass with the existing cooling circuit for the blower?

BeltFedBob

Looks like we have sun for the rest of the week. I'll say one thing for my SL55...it really loves the cold air today! Nothing like 21F for cold air induction ;-)

Heat soak, we got no stinking heat soak!!!!

320 dreamer

if only there was someway to get traction at the track with those temps!!!

SRQLAW

Thanks for all of the replies. I just got back from the dealer and spoke with my parts guy there that is pretty knowledgable. The issue is that despite there being a lot of great tuners out there - the dealer is pretty limited in who they will deal with and warranty the work i.e. Kleeman and Renntech are pretty much high on their list along with Brabus and Carlsson. So... with no disrespect to all the other guys - I pretty much need to stick with the usual suspects... b/c the warranty is very important to me and I have a 4 year 80k extended warranty which I want my dealer to continue to honor.

So, the next question is really RT vs. Kleeman. I have had a lot of good PMs with some peeps here but I would like a little more discussion. I am hearing that RT will provide more power primarily due to the increased torque vs. the Kleeman parts.

However, Kleeman has some great pricing these days in that I can get the ECU/Pulley AND headers for less than just the RT ECU/Pulley...

Thoughts????