Hello!
In my first message I mentioned preparations for 3.7 engine swap. It's already done, I just wanted to repeat what few people wrote before me - this is extremaly straightforward procedure for NA manual Crossfire, pretty much a bolt on. Donor engine was taken from 2003 (or later) SL350 with 64,000km (40,000 miles) - excellent condition with all the wiring and ancilliares for ~900 USD. Shop quoted 300$ for montage (eastern EU prices, gotta love them). So far results are way above what I expected, it is certainly a far better NA tuning base than 3,2 engine. HUGE improvement in low RPM is what strikes You first. No issues whatsoever, I still have old and beaten stock clutch, but no more slippage that usual despite significantly increased torque. Only other mod so far is straight-pipe exhaust with stock muffler cutout (see last clip).
Below some demonstration:

Dyno testing in few days to asses baseline before moving forward with next mods.

 

What ECM are you using and what are your next mods?

 

If only there was descent prices on cams, then other mods, can get 300.
save on rotational weight saves power loss to the tires, lighter wheels, tires, rotors, aluminum driveshaft, singkemass aluminum flywheel.

 

1. ECM, or ECU is a stock one, that is Bosch ME2.8. You just unplug the old engine, throw in 3.7 one, plug in and start. ECU recognizes bigger displacement and adjusts all the stuff on it's own.
2. Next mods will be related to engine and drivetrain mainly. Suspension and visual details can wait for now. Brakes will be refreshed (steel fluid lines, sport brake fluid, ceramic pads, drilled and slotted rotors) but within factory spec. Better tires of course, spacers on front and rear, as I want to stay with stock rims.

I already bought AMG fuel pump (found new one at 50% sale) and new filter, they just sit here and wait for a spare time to install:

Fuel pump code: 7.00228.51.0

First I plan on fitting DCAI, bigger throttle, and bigger exhaust manifolds - I will have a shopping spree at Needswings lol.

Second, I will get engine heads reworked. Already bought spare heads for 3.7 in good condition from scrapyard for like 300$ total, they already wait in my basement. I have custom cam and head manufacturer/workshop in my city, so I will get them to build new cams, port heads, change valves (propably bigger intake ones) and springs. My plan is to increase effective max RPM from 6,200 to 7,200, not only for pure power gain related reasons, but also wider powerband will make 1st and 2nd gear much more usable. Also, intake manifold could be rebuild with solely short runners - most propably HP increase would by far outweight the low-end torque drop - idea will need further discussion.

Third, lightweight flywheel, sport clutch and wavetrack - propably the most expensive step, as I will have to source all the stuff from third-party, expensive foreign sellers.

Fourth, got some reasonably priced heavy-machining shops in my area, so lightened crankshaft and knife-edged, forged conrods and propably pistons - got some ideas in my head about increasing CR to 12-12,5:1, everybody's so occupied with increasing boost no one tried that in NA M112 lol.
There is also that thing with stroker cams for M112, made by Brabus for 3,8 engine, but I doubt i will be able to find just a crank for sale anywhere - it would make it effectively a 4.0 engine - will see about that when the right time comes - the only two sure things are, I stay manual and naturally aspirated.

 

Please let us know what they decide on the cams, every shop I talked with said they couldn't get blanks, and didn't want to make from scratch, I couldn't even get a price on a weld and regrind.

If you are tearing everything apart, get the rotating assembly balanced.

Do you Not have your original 3.2 engine ?
same rotating assembly, heads, cans etc, only larger pistons.

For compression, since you are planning on having the heads done m, just have them taken down, so the chambers are smaller, and will increase compression.

Aluminum single mass flywheel with stell imserts and clutch is cheaper than a replacement dual mass flywheel.

There is a company also that makes aluminum flywheel and adapters to put a bmw 6 speed to a m112 & m113 engine and 450ft lbs of torque.

The m112 and m113 are really torque heavy motors, so the intake work to raise hp and lower torque would be good since the nsg370 has a torque rating of 278 ft lbs

I have wider and lighter wheels and did a single piece aluminum driveshaft.

I have had other ideas about the rear end I have wanted to try.

If you are going for rpm, I wouldn't worry about the striker crank unless you are upgrading the rods also, stroking out puts a much larger strain on the rods.
why some destroke engines to handle rpm better.

Used to know a shop that when they turned a crank they would take more off the back than the front so it would slightly increase the stroke, but was minimal, and depends on how much is allowable to turn down.

 

I tried to dyno the car, but ESP got in the way. Tried unplugging the ABS/ESP plug under the hood, also tried 4 wheel run, to fool the sensors - it cuts the power at 4k rpm.
my question is, what's the fail-safe method to dyno Crossfire? Will MB STARdiagnosis tool allow for complete turning off of ESP?
How You do it, people?

 

It is your name,,,,,,,,,,OCTANE,,,,,,, or should i say fuel... but before that and most important , what is the afr reading when it cuts out,,,,,,,,,,do you have the factory fuel filter on the car if yes i assume you know it is also a regulator ,,, if you do remove it and put in an adjustable regulator set it for 60 psi ,,it should work.,,

 

Thank You for chiming in Sir, maybe I wasn't precise enough in previous post, the ESP/ABS circuit stops the dyno run at 4k RPM, the fuelling was fine, I can rev the engine to 6k on the road all day. That's why I'm asking if there's some tried way of testing Crossfires on dyno. I read all the related topics, but there's no conclusion anywhere?

 

I was answering on what happened to one of the V8's that i installed at 4000 rpm my car would fall on it face,,,but only on the dyno on the street it would go to 5200 then cut out ,, (today to goes to 63000 ) in both places the AFR's were 14 to 17 today they are 11.9 to 12.2 this only happened on one of 4 V8"s we installed. ,,,,wheel sensors are the only thing that i can think of,,, on one of the V8's we moved the sensors to the front wheels, then dyno or burn out all you want.

 

63,000 sweet a turbine, that would be awesome

Humm wonder how big we could make fit, would not be able to use a afterburner, and the diameter of the exhaust would be a issue, but would have a awesome factor

 

LOL,,, sorry you didn;t know that was a type o,

 

Well yes, but you got to admit, that would definitely have a cool factor.
there is a company in the southern states that does turbine conversions in vehicles and road worthy.

 

that is funny because ,,when i was in the Air Force, we had a surplus store on base and i tries to buy a helicopter 1200 shaft HP jet engine this was in 1965 and i had a 64 comet i was going to put it in.

 

To totally disable the ESP/BAS system open the small black box just in front of the Battery. In there are three main fuses. They are marked. Disconnect the fuse marked for the ESP/BAS system. Nothing will slow you down, but your brakes, a tree or flashing blue lights. Be careful!

 

THANKS! Sometimes excellent info is in the shortest and most obscure post...

 

Can you use the 270hp slk engine and swap or is there more involved?