wlelandj

Hello everyone! So excited to be a new (to me) owner of an '05 SL65. So much great information on the site! I've been trying to search out all of the answers to my questions and ideas so as not to be a total One question I haven't been able to find the answer to is, seeing as the M275 is an updated/strengthened design loosely based on the M137, what parts (if any) interchange? I'm specifically interested in the intake manifold. I know we're forced induction, but the design of the stock manifold really sets off my OCD, lol. Just spit balling here (drunk on the dreams of future modifications), but a cut down M137 with laminova intercoolers and dual TB's has been rolling around my head. I know there probably wouldn't be much of a difference between that design and just using the Speedriven units, but it'd be something unique/different. Thanks.
-Leland

NEMES1S

I would think with enough fabrication work it could be possible. You would have to move a boat load of the crap that is on top of the engine though, and I'm not sure what kind of clearance you would need to get it all up and functional. I like the idea though and vote you should give it a shot!

wlelandj

Thanks, NEMES1S. So, involved enough that one might as well have a full sheet metal one fabbed up? Curse my lack of skills

NEMES1S

I would think a custom fab job would probably be easier than trying to redesign the older intake

F1BHP

Just get a custom intake made. I went with a quad pipe setup 2 to the front and 2 to the fog light area.

NEMES1S

are we talking intakes or intake manifolds?

F1BHP

Sorry I just read his post again, he was talking intake manifold. I have no idea what kind of fabricating would be needed to get that to work but it would be substantial and you would probably be better to try and get an all new manifold fabricated.

BlownV8

Intake would probably yield zero power increase without changing the manifolds or turbos. All the restriction is on the exhaust side of the biturbo V12.

NEMES1S

^ agreed. You will maybe gain a tiny bit of torque or slightly better throttle response, but in the long run the turbos and intercoolers would result in much higher gains.

wlelandj

Thanks for the input! I've been combing the forums and agree as well, my money would be better spent elsewhere. I'm definitely thinking the whole custom split intake manifold/IC/TB set up would be my last step. As you've pointed out, in the end this would amount to mostly a cosmetic/functional upgrade rather than a performance one. From my reading, besides fabbing up a CAI similar to RaceHorse's, I'll start acquiring a killer chiller, rear tank (Weistec maybe?) maybe a aquamist kit to run off my washer fluid tank (for WOT runs) and tune (Eurocharged's ecu/tcu combo deal is tempting). Excited to get started!

Viper98912

You want to replace a perfectly good '65 intake manifold, designed for the engine, with a carbon fiber engine cover; with a hacked up, untuned and not designed, older, 600 old black and silver plain intake manifold?

What the hell is up with the postings lately in the AMG forums.

F1BHP

Viper I am not sure what you are talking about. It sounds like you are referring to the engine covers.

wlelandj

Well, not when you put it that way Viper. 😅 I know that we are forced induction, so manifold design isn't as critical, but that off center/tipped over throttle body is an ugly/poor design. Probably why we have that fancy, heat trapping engine cover.😊 The whole package is an eyesore without it, imo. I was trying to cut corners/save money on design/fabrication asking about the previous models intake being able to swap. I agree with the others and you basically that my money would be better spent elsewhere, which I have said. I'd still like to explore it after everything I listed above (and then some) is done. Here a pic for reference of what I'm thinking, though I'd stagger (instead of stack) the cores and probably have the TB facing down.

Viper98912

Making something custom is different than using something "old", thinking it's going to be better, when it was never designed to be that way.

That said, if you read this forum section you'll find that people normally find the best initial bang for your buck to be an ECU/TCU tune.

RaceHorse

Start with the ECU/TCU. You will be shocked with the gains you will get from Eurocharged. Freeing up the exhaust with catless downpipes will create a need for a custom air intake for the little stock turbos, but certainly be the next big gain. Personally, I think the trunk tank and supplemental heat exchange serve much more in maintaining IAT's than larger intercoolers. The longer intercooler cores still have the outlet toward the throttle body "T" all the way to one side. Based on the velocity of the air going through the large I/C it will either pass a straight line towards the opening not utilizing the entire core, or the little turbos have to pressurize the core, making it hard to maintain boost in the higher RPMs. Either way, if the larger inter coolers pick up extra heat, it only remains in the system if you don't have an extra heat exchange. I made decent power on stock intercoolers with a trunk tank, supplemental HE and 2 pumps. I think if you go with aftermarket turbos then there may be a need for larger intercoolers. I always thought the thing to change on the intake would be making a dual throttle body setup, so all the air doesn't have to be routed back of the single throttle body. However, I can't imagine tuning that to be easy, considering MAP sensor placement. Its good to think outside the box, but start with the proven methods, and as others have said, the turbo manifolds will always be the choke point no matter how much you smooth things out elsewhere.

F1BHP

Racehorse you know these engines as well as anybody. What would it take to do a custom manifold and turbo setup, I know space is limited but would it really be that difficult?

RaceHorse

I know it will take a lot more than I am willing to dedicate to the car at this point. Since these pretty much become one-off builds, you need to personally be able to tackle it with excellent fabrication skills, great 3-D visual perception of space with no limit of time and money. If you don't have the abilities mentioned then same on the unlimited time, just more money paying someone willing to take on the task.

Once you can digest that, then you need to decide what level of power you are looking to reach, since the larger turbos fitment may need to be up top with additional relocates or elimination of factory parts. I think a slightly larger setup, in the stock location similar to what brabus made, or Wiestec is offering on the V8TTs, would be the easiest to install. It would not give you the power that could be found on much larger turbos with a header type manifold, but the entire stock drive train will need to be upgraded to handle the power from a much bigger setup. Let's not forget after finally fitting everything and beefing up the transmission, custom rear and axles, a ton of time will probably be needed for tuning. The standard ECU/TCU interaction was not fond of such high torque levels on previous builds resulting in limp mode, so stand alone software, might be required.

For the most part its not as simple as having a bolt on part when it has an impact everything else. Not to say it can't be done, as we recently saw that SL600 run a 9.9@140+ He would be the one to talk to for a legitimate budget, part list and time schedule. Fitment, turbo size, pipe size, do's and dont's could save you a ton of time and money.

In the end there is always the desire for more power and there is always another car out there faster; its just a matter of how far you want to take your car.

cal1

Hey racehorse how does your car feel at 200 MPH? Stable I am assuming.

wlelandj

Thanks for your input RaceHorse. I completely agree that the ECU/TCU is the way to go. I just want the KC/rear tank/Aquamist to, like you said, maintain whatever tune I decide on through all/most conditions. In all honesty, that's all I really need. The custom intake was mostly an aesthetic idea, but also a chance to improve on the original design. Forget about it costing as much as all of the above together.�� Speedriven's proposed (is anyone running it yet?)35R kit makes me drool though as I've always loved that turbo with it's broad efficiency, but at that level, it sounds like the transmission needs to be rebuilt.
While we're talking mods, I haven't seen a whole lot of discussion/mods on heat extraction. I'm amazed at the lack of it in the stock design as well as the sheer heat generated.�� I couldn't believe the two hood vents near the base of the windshield weren't functional(for heat extraction). I guess it's nice to have your car reach full operating temperature in a couple of minutes, but it's crazy to come back to the car after shutting it down a few hours and have it maybe be only half cooled off.�� I'm definitely considering the aftermarket hood for my '05 with the BS heat extractors. It still seems like more improvement is needed, even with that.

RaceHorse

It was stable enough to get there, I saw an indicated 203 MPH, but had to get on the brakes immediately. No real shakes I had tire pressure up near 60 PSI all around so it was a bit of a harder rider then I am use to, but it didn't feel light in the front end. I would consider doing the speed again with more shut down and more safety equipment since so much can go wrong that is unforgiving. At those speeds the last 1/2 mile goes by in less than 10 seconds.


I think dumping the Cats helps a little with the 1 hr parked heat soak. The belly pan does keep the underside clean and slippery in the air, some people remove it to allow some of the heat to escape.

I'd be curious to see the results of the killer chiller and what volume of coolant becomes the most effective. There was a small discussion on the M275 forum here regarding it.

It seems the big turbo kits offered have to be built in house. I haven't heard of any installations being done any other way, only a few setups at best. Sadly, there has never really been a great amount of information presented for others to know the true drive-ability on and off the street.

F1BHP

I am doing an event on the 26th September on a runway in the UK it is called VMAX200 HYPERMAX. All the big boys will be out and I will be one of the slower cars however I want to get to that 200MPH. The runways is 2 miles but we only get around a 1 1/2 mile run as we need to brake.

60psi on the tires? Is that the starting pressure? Is that what you would recommend?

RaceHorse

I'm trying not to thread jack so I'll keep it short. Run nitrogen in the tires if you aren't already, less pressure fluctuation with heat. I was told others run higher pressure (up to 80 PSI) to take any float out of the sidewalls of the radials. My tires were only rated to 50 but I still ran at 60 PSI. I don't know your setup to say whether you will or won't hit 200 MPH but if you are on stock brakes you won't stop in time on a 2 mile runway. I think it took me almost 1.5 miles to stop with the AMG brakes. Remember you are not really cycling the brakes a few times before a hard stop so you can't apply as much as you'd like. Maybe all this talk is getting the OP excited.

F1BHP

I will be running pilot sport cup 2 tires. I have Brembo 405mm front and 380mm rear so stopping is not an issue. I will look into finding somewhere with nitrogen to fill the tires. I am waiting for dyno results but I am guessing I will be close to 750BHP. It sounds like over 50psi is the way to go. I will be doing multiple runs, will they continue to rise?

rockthemullet

Not that it matters at this point but the M137 intake manifold bolts up to the M275. The valve covers have some bosses that would need shaved down and some solenoids would need to be relocated... but it bolts up. I have one cut apart to build better top mounts.