Then i stand corrected. I am by no means any expert on this although i do fully understand the principles invoved.

My only experience of tuning is back when to get any kind of real increase in performance required 3 things. Better breathing (inlet) Better Exhaust (outlet) as well as Better through put by the engine (Porting heads for better flow)

You had to improve all three for any real end result.

I have read a couple of USA tuners have been testing pulleys giving up to 14psi. I wouldn't fancy that myself without seein the long term implications but 3psi won't be a problem for our engines

I don't own a Supercharged Land Rover, but i do have a Supercharged Mercedes SL55 AMG.

As standard and as per it's reputation, it is indeed a real flying machine, giving near 500 BHP, and intoxicating performance to die for, and one day that certainly would have been the case, except for it's braking and handling capabilities being just as good.
Apparently if i do the pully mod and some other fairly easy work i can get it to 800 BHP.

But i have to ask myself why would i need this extra power. This vehicle already has much more power and performance than anyone really needs and also delivers it in such a usable and defined manner. There is already very little opportunity to unleash such power anyway as any car is only ever as fast as the vehicle in front
And would i want to put my Engine at possible risk for this ?

It is nice to have a bit of an edge over standard, should you ever find yourself in some competative situation and psycologically it is nice to feel at least a little bit above average if only for bragging rights alone.

So long as you will beat a standard SC and can say that you went to the trouble of uprating your Pully and have made your vehicles performance above standard, will anyone care that you opted for 6% or 10%.

My vote for the 6% option still stands as my preferred choice, but only unless you are independantly and absolutely assured that the 10% option poses no additional stress or risk to your engine and you feel confident with this risk.

After all, neither i nor any other member here will be contributing to the cost of your having to replace your engine

The SL55k is a great car. I too own a supercharged mercedes, mine has been felted by brabus. I would urge you to do the few mods to the SL

With my line of work it is easy to forget what "Real World" performance figures are. Does anyone really "need" the extra power? We specialise in twin turbo Lamborghini conversions. Also do R8s, and fezzas. All cars that 99% of people would argue are fast enough in stock form.

I will probably throw the 6 on for a couple of months and see how it goes so that I can then speak from experience then switch to the 10.

It's not something as a company we are looking to offer but like I say, when you are surrounded by 1200bhp hyper cars and The Cayenne we had was 600bhp, 385bhp just seems a little weak.

I've also considered a progressive nitrous system for real bragging rights haha

Well just to keep you updated I was driving to my garage for the 10% fitting when I get "Low Coolant" AND "Reduced engine performance"

I'm not low on coolant so guess its the floats in the water bottle

I'm now forced into limp mode every time I give push the peddle into the carpet.

I check the "backwards wiring" that was often a fault on the SC cooling pump. This has already been fixed. This leads me to think its the pump its self.

Since the car is a week old its still covered by warranty so I'm just going to give it back with a to list.

No point mapping and adding pullys to a car that's in limp mode!

When I get it back I will proceed with the mods.

Thanks for updating. Please keep this thread going. As mentioned before in my reply thread. I'm very interested in this out come and the results. I ve always toyed with this idea but didn't think it would be noticeable on top of what I already have.420bhp. I also experienced the limp mode, hot day, floored it. Mine was the electric coolant pump which needed to be re wired and replaced. Though the old one would still work if we didn't have a hot day. Cheers

Sounds like my problem... Well while its under warranty it's no "my" problem

I have personally handled cases of reverse wiring on the SC coolant Pump and the Pourus float probem, so I am suitibly impressed that you already seem to know of these common problems.

You are clearly beyond any help i can possibly offer.

Thanks, did reversing the wiring work for you?

Hi there,

Sorry to open an old thread, I've just got a 2006 rrs sc and I'm looking to do the pulley upgrade but I'm getting mixed reports as to what else I need to do. As far as I was aware the pulley is a stand alone upgrade that requires no other modifications doing to the car. Is this correct and did you notice any long term issues with the vehicle after doing this mod ?

I'll be getting a full exhaust including CAT's and a remap but I want to do it a step at a time.