I have the SL65 set up with 255/35's up front and 295/30's in the back on 8.5's in the front and 10's in the rear. That setup with those Michelins have improved the car's stick in the corners. I am definitely faster in the SL down a given stretch of road or track that anything else that I have....bar the F40 and the March...but it isn't that far off the F40!

 

I've jumped into my first Mercedes with the SL55. I have some experience owning factory supercharged cars, 2 of my others are s/c V8s. One of the reasons I bought the 55 was because I was acutely aware of the additional tuning potential of this factory s/c model. Locally, here in Australia, my existing tuning contact whom I've done a lot with in the past, tuning my now outgoing 850csi, has access to a package designed locally by the head AMG mechanic for Mercedes Melbourne. It's for the AMG 55 series equipped cars and brings their output up at least 605bhp. This package basically consists of a new pulley set, ecu reprogramming and a set of panel filters. I know this package will not be designed for running normal unleaded fuel and as it stands I run 98 octane premium in all my cars anyway regardless.

The kit is scheduled to be fitted next Friday, by my european car tuner in Sydney. I'll let everyone know how the car runs after that. I'm fairly sure the resulting performance will bring the car significantly closer to that of my Kenne Bell equipped Cobra which although not currently dyno'ed would be conservatively putting above 600 RWHP(based on other identically specced cars). Hopefully, the result will mean I own cars that give me the best of both worlds, raw musclecar performance and refined/luxury performance .

 

My install was delayed by the parts taking longer to turn up. However, it worked out superbly when I finally got it done yesterday. I took the car in to my tuner and he found the whole install a breeze. He had much praise for the engine bay room and much increased 'mechanic friendliness' that MB afford in the R230 SL's. The most difficult part, in which he is very skilled at is the micro soldering work on the ECU, which he knocked over in about 15mins flat. I was up and running in less than 3 hours, which I naturally delighted with consider the end result. We tested the car with and without the new BMC panel filters. It's definitely more responsive with the filters fitted.

The car now truly feels like a sports car and as I predicted, is now a worthy european conterpart to my worked Cobra. Probably one of the most satisfying elements is that the whole thing is so stealthy. From a parts point of view it's all factory and I would challenge even the best MB mechanics to be able to spot the difference physically. The car also as expected drives no differently than before, there are no tell tale signs of the upgrade, apart from the seat of the pants HP difference.

Unfortunately, I didn't have time yesterday get it dyno'ed, which I wanted. However, I have to take another family member's car in and leave it for some repairs, so I'll probably get my chance then in a few weeks...

 

I am happy to report that my 2003 SL55 is now limiter free!

Thanks to Oliver at Speed Tuning and to Dino for sharing his experiences with this mod.

Just placed the ECU back in service a few hours ago. Noticeably different off the line. Had K&N air filters installed per Oliver's suggestion. Soon as I can find the time and swap the tires for some Y rated Michelins I'm headed for Nevada.

I consider doing this almost as much a political statement as a performance mod. It has always annoyed the hell out of me that this car should be so handicapped by a "nanny state" bureaucrat. A simple warning that appropriate tires are required for 155+ would have been suffcient.

Off the floor 911's and Corvettes can exceeed 155, and it's really been a stone in my shoe that the AMG's couldn't do it as well because of a bit of software.

Anyway, dealing with Speed Tuning was great and I'm looking forward to my unrestricted ride.

 

Drive safely.

Just curious: I was at ///AMG in Affalterbach the other day to have my SL55 lowered (ride height optimized, which it took them approx 4 to 5 hours to do) and while I was there I asked the friendly salesperson why it takes so long for them to perform such seemingly simple tasks as electronic lowering of the suspension, or raising V-Max to 300Km/h.

His answer was this: Electronically lowering the car is a trial and error process where the AMG engeneers lower the car to what they think is right, they take it out to drive and after that read out the computer for any suspension errors. This process takes several iterations to get it 'just right', hence the couple of hours.

More on-topic here, raising V-Max from 250Km/h (155Mph) to 300Km/h (186Mph, which I didn't get done) also takes up to 6 hours for the folowing reason: The ESP, electronic braking aid, etc. software of the cars only works when the car drives less than 250Km/h. If you simply take out the speed restriction with a "software hack" all systems won't work above 250Km/h (155Mph). To have everything working as expected above the regular limited speed they have to replace A LOT (if not all) related software of the cars crucial elements. Folowed by testing with a drive and reading out the computer for any errors.

This all came out of the mouth of an AMG salesperson from which I got the impression that he knew what he was talking about.

Having said this, do you guys think that Oliver (c.s.), when 'hacking' a Mercedes AMG, takes these things into account? If not it makes for extreemly unsafe driving at very high speeds.

And another thing, while I brought my car to ///AMG they insisted that they upgrade the kompressor sealant/gasket for my build date 2002 (US MY 2003) car since that can cause problems when driving very fast for long times in a row. It is an official Mercedes upgrade (but not a recall) which you have to explicitly ask for. I don't know the part no. for it, but you may as well ask your MB dealership workshop if this upgrade applies to your car as well. This was fixed in later models.

 

Dino, thanks for sharing!! After reading your post, I think I'm gonna cotact oliver and have the ecu on my E55 upgraded as well. Those limiters are killing me, once I passed a porsche 996c2 on the highway... easily, I can see him behind from my mirrors, but after 250km, he started to catch up and went pass by me, now I'm the one in his mirrors I won't let that happen again, not after I have my limiter remove!!

 

I would hope some other people could make some comment on this more informed than my own.

In my youth I worked on tuning quite a few stock cars (without all the electronics) where the horspepower would be raised to 600+ (a 1973 911S) and the suspension would be tweaked with new shocks, springs, tires, etc. Many of these cars were run over 155 mph. They were primitive compared to the SL55 and todays tire technology. I guess I am a bit stumped on exactly what the AMG engineers were doing to the suspension, and what would be altered for 186 mph versus 155 mph. An obvious addition would be some kind of wing for downforce generation (but that's not software).

Anyone have comments on exactly what be altered in software for the suspension and brakes?

Anyone in the USA have experience with the kompressor sealant/gasket upgrade? It would seem that the real issue on this would be sustained high rpm (how much?), put the card in 3rd and drive it near redline for a few hours and you have the same conditions as sustained high speed (what number is "high speed"?) driving.

How many people on this forum have cars that can do ove 300 KPH? What has been your experience at that speed and what mods do you have?

 

Well, in their own words: Making sure all systems work as expected above 155Mph. It's purely a software thing. Apparently one of the preconditions in the standard software is that the speed cannot raise above 155, so if it does, the system becomes non-deterministic.

Their words.

Driving near, or over 155Mph for a longer period of time. The seal could start to leak some pressure throwing the engine in 'safe mode' inmediately. The upgrade is free (as in beer), at least here on this side of the pond. But it may well not be an issue with your car as this issue was fixed after the buid date of my car. But it wouldn't hurt to ask your MB dealership workshop. They can tell from the VIN wether your car applies or not.

 

Talked to the dealer today. They couldn't find any information. I'll press them to dig harder.

I notice that a lot of info is available in Europe that doesn't seem to make it here

 

The Art.Nr. (part no.) on the invoice for the kompressor job on my car is "UR230" The description is "UMBAU R230" cost "0.00". Maybe this helps you, although it may not be a universal part no.

It may have something to do with the policy of MBUSA versus DaimlerChrysler in Europe (since it is not an actual recall). However, it was the policy of the AMG plant to not let me leave without this fix. It may be the dealers policy to act ignorant since they'll have to fix it for free and it'll take half a day. Or they just really don't know.

My local dealer workshop and the dealership where I bought the car didn't notify me, or knew about this for that matter.

 

My car has had ECU work by Speedtuning USA....no limiter +extrahp/torque. I have been well over 155(202 to be exact ) and the car's systems work fine....ESP/ABC/ABS, etc.

Oliver at Speedtuning called me today and they now have a pulley upgrade to go along with the ECU mod....for about $1000. If you want to go that route, you can't beat the price!

 

Any suggestions on what tire pressure to run for high speed (>155) driving (using appropriate tires of course)?

 

When I have run over 180....I use Michelin PS2 rated for the weight/speed. I run 29F/31R. My pressures went up 1-2 pounds/corner between 180-202

 

Dino, you are inferring this is road not track driving right? I'd hate to see your SL55 going around the track with those pressures. The sound of the tire squeal alone would make hair curl.

 

On the road. At the track I run 24/26 cold PSI. They bite a bit better!

Aren'tyou watching the Aussie GP practice?

 

I can understand low track PSI traction in drag racing, but it goes against every track day I've been to. I used to think low PSI would equal good track handling but the very first BMW club track day I ever went I was quickly steered on to high PSI for reduction of sidewall flex and better cornering and quicker tire heating (I had been wondering why my very well suspended 325 had been handling like a bucket of S and squealing around every corner). No matter what track I've gone to or car I've used it's been at higher PSI levels 38+ in all cases. At the last one I went to in my Stang, one of the guys who is an instructor, did me a favor and setup my tires while I was busy attending to something else and that PSI when I checked was around 40 as I'd expected.

The GP practice sessions are not shown here on the host broadcaster during weekdays. Official broadcasting commences tomorrow. I won't be around though I'll at my farm 4wding, biking, and hunting with friends this weekend.

 

I start with low PSI at the begining of the day. After 1 session the pressures are usuaLLY AROUND 38-40 in the SL. If I start with normal pressures that I use on the street the pressures will soar and the car will slide around the corners rather than bite. In the Indycar I run around 18psi cold.

I asked you about the Aussie F1 as when you were posting last nite (my time) the practice was on live and I figured that you were playing hookey from work!! Have fun on the farm!

 

Now we're talking PSI. I was thinking about it some more and even recalled many years ago having the tire shop I use ask the Pirelli distributors what pressure to run at the track for my M3. They stated 40-41 PSI was what they'd recommend. You obviously want to be careful of the cold PSI vs. warm PSI as you don't want to end up too far over the desired mark. I wouldn't fill up a dead cold tire before hitting the track that's for sure.

Yeah, I was at work on Fri. when I wrote my last reply. If it was on I'd have been able to check it out on the TV in my office anyway, which I would have been doing if it was.

 

An old topic but i need some advice pls:


I did my limit removal and now i notice a change in the way the car changes gears; flat out from zero the car shifts smothly from 1st gear to 2nd but i noticed that the shift from 2nd to 3rd gear and the shift from 3rd to 4th gear is jerky ( not sure if that is the right word to use) it reminds me of how an M3 manual/automatic gear changes. Any of you guys noticed the same thing? and is it something i should be concerned about?

Thanks.

SL55 2003