De-restricting my R129 500SL

[KNU7S]

For some reason, I really want to get my SL de-restricted..... I don't have any where to drive is over 155mph or have ever taken it above 140mph (private road ).

I have a few questions really

1, Where can i get it done locally? (I am based in Gloucester)

2, Has anyone else had this done?

3, What sort of top speed should i get?

4, Whats a good track to try it out on??

I certainly hope my wife does not see this.

Thanks

Tim

 

[GregE240]

Er Tim, just so you know...

I've taken mine to VMAX at Bruntingthorpe several times now. It seems the 119 engine in our cars has a rather "soft" limiter fitted to it. I've had 158 out of mine, and it probably had several mph left. That said, it was almost at max revs in 4th (top) gear as mine has the 4 speed auto - same as yours?

I've no doubt you could get it done, but I'm not sure it would gain much, if any top speed.

LOVELY looking car, sir!

ATB,
Greg

 

[miro]

For some reason, I really want to get my SL de-restricted..... I don't have any where to drive is over 155mph or have ever taken it above 140mph (private road ).

Clearly that is a good reason to spend money on a delimit.

 

[stats007]

As far as I know this will require a replacement chip in the ECU - the de-restriction comes free with a remap service - the cheapest is Superchip at £300 all in IIRC.

You have a four speed gearbox so not sure what the top speed would theoretically be. The 5-speed SL500 was 176mph I think.

You'll need an airfield to get anywhere near that (or bowl) - more than likely new tyres too!

 

[KNU7S]

Thanks for that!

yes its the 4 speed, and i have heard from a few people that the 5 speed is a better gear box with better kick down....where can i get one from???

I will see if i can get Superchipped £300 is cheaper than i thought. I may carry out a few other mods to the engine and also uprate the brakes.

The car has 150,000 on the clock and still preforms very will indeed, I have had it a year now and have got allot of the small jobs done on it now, just a few bigger ones to do like the A/C compressor is leaking and i keep scuffing the underside of the front bumper!

One other thing i would like to know is, has anyone seen the 17" new SL alloys fitted to a R129??? i have a set and cant make my mind up?

Thanks for all your help

 

[imadoofus]

One other thing i would like to know is, has anyone seen the 17" new SL alloys fitted to a R129??? i have a set and cant make my mind up?

Put them on one side, take some photo's, post them here (both sides, for comparison), then sit back and wait for the opinions

PJ

 

[l5foye]

About fitting new SL wheels to your car, you should check the wheel bolt size. I recall reading that they are a different size and require adaptors. The appearance is a matter of personal taste. Keeping everything original would be my preference.

 

[KNU7S]

Good idea.......why didn't I think of that!!!!!

Thanks

 

[KLP 92]

You can't "chip" a SL 500 before 1993/4 as they don't have an electronic ECU. They have a fuel ECU which can be reprogrammed but you will suffer MPG.

You can have it delimited but rather pointless, and totally agree with Greg. I've seen a shade under 160mph on my old one and its pretty close to the red line.

 

[glojo]

The car has 150,000 on the clock and still preforms very will indeed,

Go for it, get that engine screaming.

I've taken mine to VMAX at Bruntingthorpe several times now

Hi Greg,
Did you get the oppurtunity to see how accurate your speedo was when compared to the Bruntingthorpe equipment? I recall that Maff's was surprisingly close! Most manufacturers like to have a 5% discrepancy simply to give better figures when they let journalists play with their new toys.

Regards,
John

 

[stats007]

You can't "chip" a SL 500 before 1993/4 as they don't have an electronic ECU. They have a fuel ECU which can be reprogrammed but you will suffer MPG.

You can have it delimited but rather pointless, and totally agree with Greg. I've seen a shade under 160mph on my old one and its pretty close to the red line.

The fuel map can't be reprogrammed on the early cars - hence the need for a replacement chip. I got a quote from Torquing BHP for Ian's car which is a '91 500SL so know it can be done! I agree it's pointless - as is replacing the 4-speed for a 5 - IMO you'd be better off selling and buying a later car.

 

[GregE240]

Hi Greg,
Did you get the oppurtunity to see how accurate your speedo was when compared to the Bruntingthorpe equipment? I recall that Maff's was surprisingly close! Most manufacturers like to have a 5% discrepancy simply to give better figures when they let journalists play with their new toys.

Regards,
John

Certainly did John.

158 (true) = 155 indicated.

Scarily accurate.

Hows the search going, sir?

 

[GregE240]

You can't "chip" a SL 500 before 1993/4 as they don't have an electronic ECU. They have a fuel ECU which can be reprogrammed but you will suffer MPG.

Like the 500 is frugal in original tune!!!

Nice leather upgrade on the 202 BTW mate.....

 

[GregE240]

By the way, just an observation....well, I'm hogging this thread at the moment....

At this sort of speed, I found the SL to be massively stable. Really.

OK, so my car has ADS, and it does drop the suspension above 75mph (or so), but it felt utterly planted. I threw the keys to Maff and he commented exactly the same - more stable than the CL65, which I took as a huge compliment.

Greg

 

[stats007]

Totally agree - one of the most stable high-speed cars I've driven.

 

[COUPE FREAK]

is'nt the difference between a 4 and a 5 speed box that the 5 speed is just a close ratio box and that top gear in a 5 speed box is the same ratio as in a 4 speed box in top gear,,??

 

[KNU7S]

I will have a ring round and find out what can be done, is there any other mods anyone can suggest???

My car is fitted with ADS also.

Has anyone got a price list for the 1991 range including the optional extras?

Thanks

Tim

 

[stats007]

is'nt the difference between a 4 and a 5 speed box that the 5 speed is just a close ratio box and that top gear in a 5 speed box is the same ratio as in a 4 speed box in top gear,,??

No, 5th is an overdrive (0.83 in 722.6 I believe)

 

[jjrodger]

I too read 176mph for the 5-speeder. I've seen an indicated 160mph a few times now; plenty of revs left and a little bit of go, too. I have never driven a more stable high speed car; when touring on the continent it is very happy maintaining a 100mph+ long distance average, which requires sustained cruising at 120+ and bursts up to 150 wherever safe (even the fuel consumption isn't too bad at such speeds). My view is that these cars are too fast for British roads: they are happiest above 80 or 90.

 

[BTB 500]

(even the fuel consumption isn't too bad at such speeds).

With a lot of motorway at "UK" speeds I've averaged almost 30 mpg from a tankful with mine (hard top on). It's a heavy car but low and sleek, so IMO the cruising consumption is very reasonable. It certainly uses less petrol than my 'everyday' VW Sharan (2.8 V6, similar weight).

Re. mods, I find the SL plenty fast enough but too quiet. An AMG back box made very little difference ... next step is to remove the centre muffler.