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I'm new to the forums and thought I should join to share my adventure.
I've had my SLK for 4 years (next month), and we've been through a lot together.. a couple of girlfriends, a few trips up Pikes Peak, and more recently it survived a deer.. This car was my daily driver for about 3 of those years, and I recently bought something newer (and faster... and more comfy Chrysler 200S).. but since then, I've been mulling over the idea of making my special little buddy a little bit "better".. I've been doing autocross for a couple of years (i have youtube videos if you type "slk230 autocross"), and was going to settle for better brakes and possibly some suspension work, and maybe with a little bit of money i was going to try aftermarket ECU and possibly a turbo...?
I didn't really consider the V8 swap until one came up on craigslist, complete with transmission, ECU, harness and everything still attached to the engine. and it was only $350! all things considered, it should be straight forward mechanically. the 722 transmission has a slightly different bell housing than the one with the V8, so I will just use the one I got with the V8, and from doing picture comparisons, it appears that the motor mounts are common between this V8 and the V6 that came optional in the SLK. the only (possibly) major issue I see with fitment is around the steering box. I got lucky and this engine is from a CLK, meaning the manifolds are tucked up against the engine, but i still may need to make a clearance cut on the left exhaust manifold
I believe the ECU will play with the car, as this engine is also from a 99, and I have been researching swapping the immobilizer EPROM from the SLK to the V8 ECU that way everything works from the key. aside from that, I need to figure out how the O2 sensors go into the ECU - I'm having a hard time finding ECU pinouts...
me and some buddies are going to see if we can get the engine in saturday and I am hoping for the best. there will be hurdles, but with a positive attitude, they can be overcome!
consider this a build thread, wish me luck! pictures to come!
After a long night last Saturday, I was able to get the old lump out.
prior to last Saturday I fabricated new motor mount brackets out of 1/4" plate because the mounts needed to be 1.5" closer to the engine, and 2" towards the front. I had the assumption that the V8 brackets should have worked, however i believe MB changed the motor mount location points on the frame after '99 to allow for the V6, therefore the 2.3 had different mount locations. i'll add a picture of the mounts when i can figure out where they went!
anyways, back to the action. I test fitted the V8 (which is a 4.3 from a CLK430), and overall, it fits. however i found an interference with the steering box and the A/C lines did not want to fit. After pulling the A/C compressor and removing the left exhaust manifold, i was able to get a good idea of how the engine fits inside the bay!
that steering box is a big issue... apparently after 2000, MB relocated the steering box lower, for the bigger engine. mine, of course, is very much so in the way. I'm thinking rack and pinion conversion..
I would just like to update that the swap is basically complete. There are a few things I am going to re-work in the next month or so, but the car is running and driving pretty well. It functions just as it would from the factory, even the cruise control.
I'm assuming by looking at the pictures, you had the 3.2 V6 in originally? I'm curious to see how the engine mounts hold after time. What transmission did you use? Custom driveline? If not which driveline did you use? Did this swap require custom transmission mounts? I'm very interested in this build. Any videos of the car?
I'm assuming by looking at the pictures, you had the 3.2 V6 in originally? I'm curious to see how the engine mounts hold after time. What transmission did you use? Custom driveline? If not which driveline did you use? Did this swap require custom transmission mounts? I'm very interested in this build. Any videos of the car?
This was an SLK230 with the 4 cylinder, which made the swap a little bit more difficult due to the location of the steering box. SLK320's had the box mounted lower, the ECU box was smaller and the firewall would have been different.
So here are some details. it has stock engine mounts, but the brackets to the engine are 1/4" steel - they will hold! I used a 722.6 that came with the V8. the 4 cyl and V8 use a different bell housing, although the bell housings will swap between the two. nothing custom - SLK drive shaft fit up nearly perfect. no custom transmission mounts although I needed to space the engine and transmission 1/2" forward in order to make room for the intake piping. This is something I'm going to correct in a couple of weeks.
This was an SLK230 with the 4 cylinder, which made the swap a little bit more difficult due to the location of the steering box. SLK320's had the box mounted lower, the ECU box was smaller and the firewall would have been different.
So here are some details. it has stock engine mounts, but the brackets to the engine are 1/4" steel - they will hold! I used a 722.6 that came with the V8. the 4 cyl and V8 use a different bell housing, although the bell housings will swap between the two. nothing custom - SLK drive shaft fit up nearly perfect. no custom transmission mounts although I needed to space the engine and transmission 1/2" forward in order to make room for the intake piping. This is something I'm going to correct in a couple of weeks.
Very impressive, I am extremely surprised the drive shaft and transmission mounts worked! Sounds to me like Mercedes engineers were thinking.
How did you overcome the steering box issue? Also, how did you deal with the wiring? Was it plug-and-play?
I converted the car to rack and pinion from an E430. It took a little fabrication. Wiring WAS NOT plug and play. I'm using MegaSquirt fuel injection and Electronic distributor-less Ignition. everything else is ran by the stock SLK ECU.
Kudo’s for doing the swap you wanted.
When you say aftermarket fuel management that means a piggy back? The V8 didn’t have the same pinout? The W208 (CLK) cars can swap V8 to a 6 car with the accompanying motor ECU
I owned a W208 430. I liked the motor. Looking forward to see a video of the car running
Kudo’s for doing the swap you wanted.
When you say aftermarket fuel management that means a piggy back? The V8 didn’t have the same pinout? The W208 (CLK) cars can swap V8 to a 6 car with the accompanying motor ECU
I owned a W208 430. I liked the motor. Looking forward to see a video of the car running
There were too many differences between the SLK and the CLK ECU's. there was also the astronomical task of getting DAS to cooperate. I even had a V8 ECU wiped clean by Beckmann Technologies and bought STAR DAS to program it, then ran into issues with the Mulitplexer. that's when I decided to just go with the Megasquirt II ECU. really glad I did too - unlimited tunability for if/when I put a larger M113 in.
more specifically, Ignition is being controlled by EDIS (used on ford V8's). so it has 2 coil packs nesting below the engine cover - and that all gets it's signal from a 36-1 tooth wheel that I fitted on the crankshaft. So basically the engine has spark plug wires going to each cylinder instead of coil-on-plug.
The original SLK ECU is managing throttle and the transmission. It sets Idle position based on temperature and engine RPM, so basically the SLK is controlling the hard stuff.
you can see the build here: http://www.slkworld.com/performance-...v8-swap-8.html
It's not necessarily a "professional" install, but it is improving as I go.
I take my hat off to anyone using a megasquirt. Glad you are getting decent results. Tuning those things are not for novices or those not willing to do a lot of background R&D.
About the ignition with respect to M113 motors. The system has 2 plugs per cyl. and fires both at different timing degrees for power and emission purposes.
Not sure if a MS can handle that or the aftermarket coils fire 2 plugs per hole without a reduced spark. It may have reduction in power, intake and exhaust contamination also due to the 3 valve head and camshaft timing
I watched the gauge video and remembered how long the trans take to shift. There are ways to shorten shift times that can help.
If you’re using the DBW throttle another way to quicken up response is trying Sprintbooster
Keep up the good work
Hary
Posting here because I have bought a Crossfire (based off the R170) and I also bought a wrecked CLK 55 AMG as a donor car to do an engine swap over to the crossfire. My grandfather does body work and is 73 and LOVES crossfire's so it's going to be our last project car together to turn the crossfire into a V8 show car! If anyone has any advice on what all we need to do to swap the engine over (I was already told the ECU and TCU will need reprogrammed from the CLK 55). I was also told to get new long tube headers for the 55 AMG to relieve backpressure because of it being a smaller space in the crossfire. But I'm not sure what else needs done. I know it's not a "get your money back out of it, investment) but as stated earlier it's much more about having one final project with my grandfather and I never plan on selling the car anyways. So whatever money I have to put into it is totally worth it!
Posting here because I have bought a Crossfire (based off the R170) and I also bought a wrecked CLK 55 AMG as a donor car to do an engine swap over to the crossfire. My grandfather does body work and is 73 and LOVES crossfire's so it's going to be our last project car together to turn the crossfire into a V8 show car! If anyone has any advice on what all we need to do to swap the engine over (I was already told the ECU and TCU will need reprogrammed from the CLK 55). I was also told to get new long tube headers for the 55 AMG to relieve backpressure because of it being a smaller space in the crossfire. But I'm not sure what else needs done. I know it's not a "get your money back out of it, investment) but as stated earlier it's much more about having one final project with my grandfather and I never plan on selling the car anyways. So whatever money I have to put into it is totally worth it!
go to SLK world and look at Dave2302's build. (mine is also on there too) but His uses all MB stock stuff and can also help you with the programing stuff. There is also MSS (Mercedes Swap Shop) that does a lot of these as well. you can find them on FB and i'd bet here somewhere.
You are off to the best start with the CLK because of the exhaust manifold and how it arches over the steering box. other MB models do not have that. This unfortunately means long tubes will not work. You will want to cut the cats out (or remove the cat material like I did)
Mechanically it's quite easy and will bolt in for the most part. the Electronics are a little challenging and can be expensive, but there are new options for solving that every day.
Wow this page never really got updated! Looks like the last time you guys saw it, it had the 4.3L from a CLK in it. SINCE THEN I was able to acquire a 2001 CLK55 AMG. My original intent was to use that as it is, but ended up having title issues.
At the same time, I bought a manual transmission conversion (for a Chrysler Crossfire) off of ebay for $1000, and swapped everything including the AMG 5.4L in and went from there.
After that was all together, I swapped in the 2.82 diff from the CLK and also the half shafts, then also swapped the coil springs, sway bars and brake rotors and calipers.
Running MegaSquirt fuel injection, stock throttle control so it still has cruise control and a smooth idle.
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Nice build here.
From where I am doing such a thing would be amazing for car enthusiasts. For the authorities would mean a group dinner after fining you, submetting to a special inspection, impounding the car and have you re-install the original gear.
Was it originally automatic? Noticed because of the rev limiter.
There's still some roll. With a stiffer sway bar possible you could shave some seconds for forcing the tyre to contact the road.
By the way, was the SLK diff already pass its limits for the V8 5.5?
Nice build here.
From where I am doing such a thing would be amazing for car enthusiasts. For the authorities would mean a group dinner after fining you, submetting to a special inspection, impounding the car and have you re-install the original gear.
Was it originally automatic? Noticed because of the rev limiter.
There's still some roll. With a stiffer sway bar possible you could shave some seconds for forcing the tyre to contact the road.
By the way, was the SLK diff already pass its limits for the V8 5.5?
Kudos to you sir! Keep this updated.
yes, original Automatic. Was an Automatic while it had the 4.3L in it, and then for a couple months while being a 5.4L. The bigger diff was a later upgrade as well, so the original 4 cylinder diff held up just fine.
Also, it has the bigger sway bar from the CLK AMG and also I just installed the rear sway bar and it helped the roll a BUNCH. however now I lift a rear wheel and have no traction!
02-16-2017, 12:12 PM
all things considered, it should be straight forward mechanically. the 722 transmission has a slightly different bell housing than the one with the V8, so I will just use the one I got with the V8, and from doing picture comparisons, it appears that the motor mounts are common between this V8 and the V6 that came optional in the SLK. the only (possibly) major issue I see with fitment is around the steering box. I got lucky and this engine is from a CLK, meaning the manifolds are tucked up against the engine, but i still may need to make a clearance cut on the left exhaust manifold
