NellyRod

I wanted to share this with everyone and get opinions on the results. Before anything, let me say that I'm happy with the performance of the car after the mods and the OE tune.

The first run file is with the stage 1 ECU tune (no mods, just tune). The second run file is the stage 2 ECU tune, with all the mods listed in my signature. I don't have a stock baseline from this particular dyno, but I want to ask what you all thought about the gains from stage 1 to stage 2. This dyno runs low. My baseline on a different machine was 430 WHP stock, no tune. Clearly irrelevant, but just showing how much numbers will vary from different dynos. Opinions? Do you think the high flow cats are being too restrictive? Car runs smooth, with no CEL or hiccups, but I'm seeing huge number differences from other M156 with similar mods, and even though they're on different machines, the delta is much too large to say it's just the dyno. How are you guys getting 470 to 490 WHP SAE with similar mods?

solekeeper

god i dont care what your numbers are. just post pics of it, i love it so much.


and you don't have ADV.1 wheels on it, thank god.

Mort

I remember a post from a while ago and the owner wanted cali legal cats on his car. He had MBH headers and saw a 20 hp decrease with the cats installed. Gives you an idea of approximately how much the cats may be costing in terms of your results. The difference in results may in fact all be attributed to the dyno type, geographic location, weather conditions and how the operator has it set up to give feel good results and less upset customers. So 20 - 30 hp from the dyno set up and 20 - 25 for the cats and you have 473 - 488 at the wheels. Now go back to the machine you got your baseline results on and see what you get and add ~ 20 hp for the cats. I think you will be in the 470 - 490 range.

avery.whss

No idea...but you're numbers look a little low for a BS?? I thought BS was like 550hp?...the dyno I had my 09 on is known to run a tiny bit high but even after mine was corrected and all said and done I still put down just over 470whp with a tune...I do know that from reading all C63 engines are different...it seems like some run a little low and some run a little high...I know it sucks? I've seen guys dyno's at like 330ish stock and then another guy same dyno and all run closer to 400...IDK? Anyways sick car either way.

NellyRod

Your math makes sense. I did have the car dynoed on the same machine that gave me 430 WHP stock a few days later, and with all the mods it dynoed 450 WHP. So if I were to remove the high flow cats, it might have read ~470. Thank you for the explanation. I might get catless mids just to test this theory. I had catless mids on my last C63, and the fumes were intense.

NellyRod

Thanks! Here are pics from a photo shoot we did a little while back. Enjoy

https://mbworld.org/forums/c63-amg-w...rojects-4.html

NellyRod

Yeah, I thought the same thing, which is why I posted this thread. Like I said, the car feels strong and performs great. I was just curious if I was missing something because it seems that all the other M156 engines with headers and tune are running stronger. I'm not a huge fan of dynos to begin with, and I'm not chasing numbers either. I just didn't realize that high flow cats could be so restrictive, and possibly the cause of the small delta between my before and after. Thanks for the compliment. The car really does look sinister.

abcut973

Yeah numbers are kind of low but it doesn't matter. What you want is the gain over stock or baseline. You gain roughly 24whp with headers over a simple tune. You probably lost 20+whp with CATs. What we usually see is nearly 100whp gain over stock catless. Looks like you're right on the par

neoprufrok

Thanks for posting. Would have been nice to know exactly what the gains were. Any way you could get back to the other dyno?

Faris63

I was in the same situation as you my C63 dyno'd 399WHP on OE tune then I installed headers and got the tune updated for headers after that I dyno'd my car and gained only 40WHP when other cars with same combo with different tune put on the same dyno 480-490WHP. After I sold my car the buyer decided to put on other tune which added another 30WHP over the old tune.I don't care about dyno number either but I like to compare my mods on the same dyno to know if I gained anything from the mod

NellyRod

I did end up going to the original machine that I got my baseline stock dyno. Completely stock it dynod 430. Then after all the mods in my signature, it dynod 450. A very pricey 20 whp gain, but I'm also running high flow cats, and a "canned" tune. I'm sure if I use catless mids and take the car to OE for a custom tune, I would see an additional 20 whp or so.

johnnyblaze

Thats about right on target, my non-p31 dyno'd 445 with secondary cats in.

Jbizzy21

The BS seems to be a little bit finicky on the dyno. I know when we had mine on the dyno, things had to be adjusted several times because it was under performing ... I remember the first reading they got as well was only about 405whp stock...eventually after doing some research on the car(first time dynoing one for the company I used), it went up and ended around 430ish stock. Then when we did the headers and tune, originally it only came out to about 450, but I think as the computer started to adjust, the numbers went up, and by the end it was about 480whp. Ultimately, I payno aattention to the dyno number on this car; I had a legit 500whp E63 M6 for 6 years before I sold it this summer, and I know for a fact my CBS was faster than that car was by about a full second 60-130 on the same stretch of road in identical conditions.

NellyRod

Seems like the BS has a bit of an attitude problem when adjusting to ECU tunes. I figured it would be the same as any other C63, but I'm not a tuner.