focituner2

Hi All,
New member here and new to the Mercedes platform as well. I just picked up an 09" C-300 sport 4matic with 15,000 miles. I have a goal set for the car at 300hp and would like to see how I can achieve it. Any recommendations as for parts/tuning and companies to get these parts from would be greatly appreciated! thanks!
I live in the chicago area if that helps.

AKnight55

Sell it or find a new car. Not going to happen unless you spend big money

focituner2

Hah i was afraid this would be the answer. This is my DD mainly for commuting to work so i'm just looking for more fun on the drive. If i want all out performance, i have other toys for that.

vanir

In naturally aspirated stock engines designed for docile traffic manners, quietness and comfort achieving 1hp/cid is the general measure for a high efficency engine with very good performance. Most off the shelf passenger sedan engines are below this marque, Mercedes has long since held the measure as an engineering requirement which is why an early 70s Merc with a little 2.5 or 2.8 litre six performs just like a similar size Ford contemporary with a 3.3 litre or 4.2 litre engine respectively...only better. An ohv iron block 163cid engine from a major local manufacturer would be lucky to put out 115hp and a 186cid 125hp in 1972. A Merc 170cid put out 170-190hp in euro config depending whether it had jetronic or carb.

In the world of engine modifications from aftermarket tune shops, the whole idea has been these stock wheezy local engines needed lots of improvements to bring them up to that Merc standard, flow rates, parts matching, tuning of components, yet the goal remained the same and one players like Mercedes already achieved at the factory.
To do a nice aftermarket mod tune on your local make 186cid ohv six, we're talking racing homologation here, big multiple carbs, lumpy camshaft, oodles of headwork and nice tuned exhaust, not to mention complete restrengthening and rebalancing of the bottom end, running into big dollars of mods, achievements for say the GTR XU-1 3.0 litre managed 160hp from the 186cid, in full track configuration ready for racing, 185hp.
Yup, 1hp/cid. That's 70s race track quality performance. I had one of those cars myself.

So the first thing to understand is from a tuning/mod shop performance perspective most of the work on the bulk of Mercedes engines, especially the later ones is already done. Swapping any components for aftermarket hi-po ones is more likely to actually decrease outputs than increase them, it already has great high performance quality engineering in every component with a lot more money spent on research and development than any aftermarket manufacturer.

The fact your stock 3.0 litre V6 has a rated 230hp from around 183cid means it's already pumping race track specifications off the shelf. You could put it, as is in an open wheeler rwd chassis and race competitively in a 3.0 litre engine class...it's that good on outputs for that size. It's astonishing that with that kind of power from that capacity, the thing remains a docile, quiet, comfortable passenger sedan.

So engine performance wise, that 3.0 litre is already pumping a ton for its class. You're talking about aiming for another 70hp gain on it? That's no small thing from where you're at. If it was a 70s Ford/Chev/etc. 185cid engine with 130hp sure you could aim for a 70hp increase n/a and the final goal would be at 200hp, which would take lumpy cams and a full re-engineering to achieve and cost a packet, but it's right there to do.
But from this engine? Only way you're going to get it is forced induction and a pretty big spec on it. Big, big dollars.

If you've a compact sedan with 230hp from a 3.0l six and you feel it's a bit sluggish, it's entirely because AWD systems and a 7-speed auto transmission are heavy items.
Your best choices are along the lines of keeping it in lower gear longer and keep your engine speed up in the max performance range more often, to be using higher hp most of the time in normal driving...or more cubic inches to offset the AWD/trannie weight. The later C300 is 3.5 litre, find out how much swapping yours for one of those would cost. That's worth 30-40hp. But this wanting another 70hp thing...you're talking about swapping out the V6 for a turbo V8 or something...that's the class you're thinking in.
Don't get caught up in the mainstream manufacturers marketing strategy of advertising ridiculous kilowattage power outputs on their cars, it's just that, a marketing strategy. I don't know what hair brained method they're using to measure these advertised ratings like 300kW in a stock chev sedan with barely a burbling exhaust note, but a 10-sec super street drag car rocking and snorting like a mad bull is lucky to put out 300kW, I call bullcrap on manufacturer output marketing.

Forget hp goals like 300 from your little V6. Go from ground up engineering point of view. It's already very tough. You need cubic inches to improve, or can supercharge (mech or turbo) to substitute cid. No other way.

aussie e55

very well written are u in australia ?.

focituner2

Thank you for the very thought out write up. I was under the impression that there was room for improvement within the engine. With tunes averaging a 25hp gain, I was assuming that if there were options to help the motor breathe easier this goal wasn't too farfetched.
Does anyone make superchargers for this motor? If not, I guess I'll have to put my education to use and see what I can do with one of these.
http://www.vortechsuperchargers.com/product.php?p=13

vanir

Well firstly the Vortec range is about the only shelf blower capable of handling your requirements, every other brand is way undersized and so is the particular model you picked. FYI the "cfm rating" is really an "island cfm rating" which is a turbo measure and not related to n/a induction cfm ratings. You think of them more like a fuel bowl and you tune the gears/pulleys for the boost curve within the engine speed range you want and regulate it with a casing valve. For 300hp from a 3.0 litre capacity you want about 1200 island-cfm rating and custom pulleys to get the oversize blower's impeller speed up near max at max engine speed, for peak efficiency in the driving range whilst maintaining good boost at lower engine speeds. Use a valve to top out max boost halfway up the range.
Like I said you're talking about race track or supercar outputs wanting 300 horses from that capacity, meaning race track setup. Just not going to get there otherwise and it's big dollars any way you cut it.

A much better alternative is swapping for the 3.5 litre V6 and putting a low blow like the V5F on that, tuned for 48000rpm at max engine speed it should be about 0.7bar right where you want it, whilst still delivering good outputs at low rpm using simple cubic inches. Bonus points being you don't have to rebuild the whole engine for low compression to handle 1.8bar you need for 300hp from 3.0 litres. A little under 1bar will get you 300hp from 3.5 litres nicely and smoothly, most of the time you'll run at something like 0.2bar and you might get away with simple head spacers, extra injectors (richer fuel under boost lowers ping) and cooler plugs, or water injection for the all out full throttle operation.

Engine changeover cost aside, that's the much easier, cheaper and softer alternative. Going it with the 3.0 litre is talking serious race spec on a small engine in an overweighted car, the AWD and trans makes the compact more like a large car. The AMG version is what, a biturbo V8? V12? You'll get it moving along nicely with a blown 3.0 but it'll be heavy on the boost and need seriously oversized blowing to make sure the lower engine speeds aren't going to suffer for your top end 300 horses. This is all much easier and smarter with a 3.5 litre with a lower blow and provide the benefits of a more tractable, softer setup for the same ultimate performance gains. Reason why AMG always starts with upping capacities on hotrod Mercs.

Yes you're right in goals like 25hp being much easier to achieve, and can be done with tuning but you're talking 70hp increases and it's exponential, getting harder the higher the starting point. The stock engine already has a high starting point.

What you can do and if keeping this car with this engine and a reasonable budget...
...is make some personal bargains between comfort and performance. Like this, exhaust note is just going to be what it's going to be. Take it to custom race builder and exhaust fabrication specialist for some tuned length primaries, the stock system from the collector back flows plenty for 500hp if you want it to, but there's some gains in the primaries with square tubing as far as they can poke 90-degrees from the ports in the bay, oversized in tubing to the ports and long as possible to the collectors, with some heat insulation. This is going to cost something like 3K but that could be worth 15-25hp at high engine speeds depending what else we do.

Forget porting, forget bottom end, forget induction, forget spark tuning, these all flow/tune stock far and away more than anything you could possibly ask from this engine naturally aspirated. With the standard maximum engine speed and 230 stock hp trust me those heads flow just fine for as much as you can possibly get. Stock Mercedes bottom end tolerances and balancing variations are nothing short of race quality piston/rod kits for track motors and they've been doing that since 1970, I've compared them. Point is there's just nothing to be gained but a lightened bank account here.

You can possibly tune reciprocal mass for quicker spins up top end with a piston kit (race alloy compositions) but it's a lot of expense for thimble sized horsepower gains you're just not going to see 90% of the time driving. The stock setup is just that good, I'm not kidding.

Even the cam/valve timing is troublesome to play with and doesn't have a lot of potential for gains, it's variable to start with and delivers the best of both worlds for drivability and performance, but with some probably very expensive procurement you might be able to sacrifice some bottom end grunt for some top end hp gains. A little more overlap between intake/exhaust and a little more lift will do it.

Upping the intake valve diameter will slow gas velocities at low engine speeds and sacrifice some response but allow higher rates at higher engine speeds for some hp gains. Again this isn't going to make much difference 90% of the time in daily driving and cost a lot.

An aftermarket intake filter in a hi-flo cotton or foam design within the stock air cleaner box will help make the most of it.

A custom, dyno calibrated chip reconfiguration will lend you the maximum benefits of the engine's mechanical engineering/setup with an elective emphasis on performance over drivability but I wouldn't go believing advertised bolt in hp ratings on chip mods. It's just a tuning thing and the hp increase has to be latent in the mechanical setup firstly.

Really the best bolt in increase is going to be swapping the 3.0 for the 3.5 litre, it's a straight up 30-40hp. You're definitely going to feel that and it's most of what you want. Seems expensive though, but probably cheaper than getting it from a blower, let alone surpassing it greatly.

@aussie e55, yup I'm in Melbourne.

focituner2

Once again, very valid points. I am building a race prepped ford focus and have come across these issues and definitely do not want to go through that again with this car. Normally, auto manufactuers play on the safer side of performance based of the principles of reliability and cost. I am unfamiliar of the Mercedes platform and am learning that they didn't cut corners. I certainly understand that an output of 228hp is quite the feat being N/A but like I said, I was under the impression that the output was more on the conservative side.
That being said what are the physical differences between the 3.0 and 3.5? I have been trying to find engine schematics/ pictures so I can better understand it.

vanir

The engine code is for the same family, M272KE30 for the 3.0 and M272KE35 for the 3.5 and both should have the same anciliaries and external equipment for a bolt in changeover, but you should change engine/trans as a unit because the shift control for the auto would be different. You'd also need to swap out the ECU for the bigger engine. Other than that you should be able to bolt everything from one to the other, like injection, manifolding, etc.

There is another 3.5 litre version called the M272DE35 which uses a different (direct) injection system. If you swapped for that you'd have to buy the engine/trans with all accessories and could only bolt up the exhaust from the old engine. It would be a far more expensive proposition. It does have a lot more power/efficiency than the port injection 3.5 but unless you've oodles of money to spend you'll be happy with the extra 40 horses of the regular 3.5

If you really wanted your 300hp though, the direct injection 3.5 puts out 290. Obviously as you can probably guess I'm learning on the fly about your engine as I look up bits and pieces here and there on the web, but the basic rules are common and I had a good idea of what they'd be.

The outputs aren't at all on the conservative side, it's just that technology is at such a point with these engines that all the N/A go faster mods are already on them, but they still drive sedately in traffic and don't sound race bred or anything. But like I said even the valve timing which is one of the most central means to retuning a performance engine, in these they're variable for up to 40-degrees. For a race tuner it goes like this, in sedate shopping trolley engines you want about 250-degrees total duration at the most, or else it starts sounding lopey like a performance engine and loses the smooth silence of a luxury sedan. At about 270-degrees it starts to sound a bit like a Porsche with a definite grunt note and burble at idle, there's a fair bit of inlet/exhaust overlap. At 290-300 degrees it rocks and snorts like most cars on a race track and that makes sense because that's a race grind. Okay so the variable cams on the M272 go to about 280 degrees at full throttle/high rpm. At the other end of the scale the problem with more valve duration is the overlap and loss of bottom end performance, if you want really nice table manners and never need to rev past 5000 then a sedate 240-degrees is the way to go, it'll pull like a truck at 1500rpm.
So this is how Mercedes is getting the best of both worlds here, and you can only make very slight improvement, at quite a cost to squeeze a couple more horsepower way up top and a few more revs, but giving up some of that fantastic bottom end performance in daily driving. Imagine cruising at a comfortable low rpm doing 30mph and you come to a hill and it has less power than it did before. But if you feel like burning a ton of fuel you can downshift and up the rpm and it has more than it did before, but every time you come to a big hill you have to use higher revs than you used to, it gets annoying believe me. That's what you'd be doing to it. In the real world actually reducing usable power the bulk of the time. See how that works?

These are already ball tearers in their engine class, it's just deceptive that they're so sedate and relaxed about it. Don't be fooled.
You'd sacrifice a lot of drivability for microscopic gains trying to retune them N/A.

What should be a bolt in 3.5 changeover will net you 270hp, if you go the expense of the direct injected version 290hp.

Best you could do is *possibly* net some 3-4% increase with tuned tubular exhaust manifolding bolted to the stock system. There's your 300hp, but even 275hp or so will feel like a real powerhouse with the pedal to the floor and the rpm up.

My little 190E has only 160hp but really feels toey in the upper range, I get a chirp of wheelspin with 205 tyres in the full throttle 1st-2nd gearchange. It takes a pretty quick car to beat it, despite driving like a four when sedate, the two extremes of driving modes already prevalent in older Mercs. And really it's like a dinosaur compared to yours, the C-class being like a technological progression of the 190E. Same themes, but miles ahead.
So think of that 160hp as your car class' starting point, it was. I can do things like change the cam (it's on order), uprate exhaust system, chasing 180hp. If I switch for the inline 3.0 more like chasing 200hp. Look how far ahead of that you start with, it's really the same class of car, just older tech. Not much to improve with yours.

smo0othride

Vanir, you have some extremely thorough responses. A 190E 2.6 was my first mercedes, and they are very fun to drive, but I lost respect for it when a civic beat me in a race.

vanir

The contemporary (84) civic is the third generation 1.5 litre SOHC with 90hp @ca.1100kg kerb weight, I really don't think you're talking about one of those civics.

The later (90) VTec is contemporary of the M104 for production year and technology period. The M103 remained in production with the 190E for a few more years, but the M104 was already in the E, S and TE classes and was planned before that but Mercedes were forced to wait.

Variable valve timing technology (VTec) was already used in racing but Honda suddenly took a domestic patent for the passenger car market and until it expired other manufacturers were forced to wait a year or so before placing their variable valve designs into production, or otherwise use a less effective variation of this technology (which Mazda for example did, Mercedes decided to wait).

The true contemporary for the 4th gen VTec Honda then is really the C280 with 195PS @ 5500rpm to the Civic's 160PS @ 7600rpm, and 200ft/lbs @ 3750rpm to Honda's 112ft/lbs @ 4000rpm. What those figures mean is with skilled piloting there is no way on god's little green earth an early VTec Civic will beat the Mercedes contemporary variable cam timing compact domestic, irrespective of a couple of hundred kgs kerb weight. Not at any speed under any conditions.

There is a kind of in-between series Civic layout in both 3rd gen and 4th gen bodies, the 1.6 litre DOHC non-VTec (D series) motor was available in Japan in 85 and exports in 90 but this pumps 130PS at best and a 190E 2.6 in good tune should run about even.

I do appreciate what you're saying as a driver experience. I used to have a local 70s musclecar in the 3.3 litre class of the type that used to compete with the 5.7 litre V8s on the track (won the national touring race in 72). In the 80s that was a real ball tearer on the roads, lumpy cam, multiple carbies, spin wheels at 40mph, then a spanking new Civic VTec with a rice cooker tailpipe rolled up at the street drags and left me for dead, like I was standing still, it was embarressing but more disconcerting, it took all the fun of owning/driving that car around. I needed to get with the times and up my technology for a daily driver.

I'm still being impressed by the difference between a 1970 sportscar and a stock 1989 Mercedes shopping trolley. It took over 200hp to punch my Torana through the wind past 200km/h, the 190E does it with about 150hp no worries. High speed acceleration is better using far less power or fuel. And even sticking with the 2.6 the motor has 220ft/lbs of torque to tap and that means there's really no drama aiming for 200hp or thereabouts with a lopey idle and some dollars.
Many on Mercedes forums talk about an easy M104 bolt in for the 190E, using the early CIS-E versions. That's worth 215-270hp.
Even a very simple M103 swap for the 3.0 litre is an easy 180-220hp stock to warmed over.

Drivers who own a 190E with the M103 3.0 bolted in stock, rave that it's a rather quick and responsive change.

I just like the way mine owes me a mere 3-grand total, including purchase cost and has hundreds of thousands of kms of life in it, and drives great compared to much more expensive alternatives. Qualitively it drives awesome, performance wise acceptable but I'm improving it as I go. And by "acceptable" I mean I often have to test acceleration on the roads against annoying traffic, and ran side by side with a 90s injected 5.0 litre (holden) V8 last week and a 3.8 litre (buick) injected V6 the week before that, both in compact sedans and both were seriously trying to beat me into the weeds and couldn't get past.
I regularly run even with current model twin cam 3.0 litre V6 Japanese compacts but people don't wind their new cars right out, just talking off the line for a short squirt with those, they try to blow me off, it doesn't happen as they were expecting, they give up, I get ahead.
Any sportscar or sports version of a compact will beat it, but not the vast majority of regular domestics advertising far more output than mine. Either drivers don't know how to drive anymore or the old 190E still compares surprisingly well being so outdated in the technology stakes.

smo0othride

To be fair I should mention it was a Civic SI, probably a 98 and my 190E was an 88. Also, it was from a stop. I know if it was a race from 60mph to 100mph that the 190E probably would win.

My favorite performance mod that I did to my 190E was to take the springs from a 90's 500SL, cut them and install them on the 190E. That paired with 225 tires made the 190E able to take turns at any speed desired (the 225's did rub). Amazingly the ride was still reasonably smooth as well.

I remember very clearly that it would top out at 128mph, and often drove it in the 100+ mph range (desert areas in cali) which it seemed very comfortable doing, something I definitely wouldn't like to experience in a civic.

Unfortuntely the odometer had been replaced around 20,000 miles which made the car almost worthless when I went to sell it.

Sorry to the OP for going off topic

Blickling

Tune, bigger throttle body like other n/a Benz motors, air filters and exhaust might get you somewhat close to your goal. If you're talking 300hp at the wheels you need forced induction, but 300 hp at the crank like a 2013 c350 probably isn't too unrealistic.

Good luck! I have 300 from factory and am chasing 330-350. See how we go.

oldsinner111

I make 355 hp with my m104

vanir

Nitrous is illegal on street cars in Oz. You can have it fitted for a road/race daily driver but you can only connect it up at the track and you must have identification plates showing to warn emergency crews if you have a car accident (fires love a sudden burst of oxygen). Finally, police are not required to have probable cause to pull you over in Australia, they can pull you over for a random breathalyzer check, a roadworthy inspection, a license check, any reason they feel like. Cars with NOS plating get pulled over and checked.
Otherwise I dare say there'd be a lot of 250-350hp 90s cars running around. At the track a favourite little pastime was buying ex-taxis dirt cheap and bolting nitrous on for a blast. Engine only lasted a few runs but it was cheap fast thrills.


I put a dbilas camshaft and 63mm exhaust/performance-cat on the 2.6 which made a huge difference, it's got a full mm more valve lift. Crazy thing is I think economy actually improved to boot. Should be pumping about 185 through an engine exhaust brake. By the standards of an 80s car it really does have a fair bit of grunt above 4000rpm now. But modern cars have tons of torque off idle and electronic managed shifting so racing beside one is like watching a bouncing ball, they're quicker no wait, now I'm quicker, oh no gear shift they're quicker again...

Currently sorting a 3.0 change with a race prepped head though, chasing 230PS which should be just fine in a light W201. The main thing is it'll be a huge torque increase at medium engine speeds and part throttle, meaning it'll be worlds better in stop/start traffic conditions.

I'd love to supercharge it but the expense to do that in this country plus the necessary EFI conversion to control spark, well let's just say I saw a couple of C36 AMGs for sale asking 10K recently and that'd probably be cheaper...

Exotic-metal55

Even to get 70 more HP at the crank would be near impossible with bolt ons for a small N/A engine. Cheapest way; would be to put a single turbo on.

vanir

Unless you want to put that turbo on in Australia...

Just an EFI conversion costs 5 grand upwards locally. Fabbed mans alone cost 2-3 ea. A basic turbo setup an American might've spent 3-4 grand bolting up would cost 8-10 here. Unless there's a factory kit specific to the engine so nobody has to fab anything and no conversions need to be made, everybody goes n/a around here on everything.
That said, the stock family station wagon holden v8 straight from the dealer has 270kw and a 14 second quarter mile...
In clubsport version, 318kw and you still can barely hear it idling. Tough competition from housewives. Kinda discouraging for the weekend modders.

And even Mercedes jumped on that bandwagon, no more gutsy little tuned i6s in a current AMG anything, it's all earthquake 6.2 litres and forced induction even on the same chassis they put the 1.8 fours into. I kinda miss the 90s...