Hi guys
I own a 2010 supercharged rrs which is getting fitted with the smaller diameter supercharger pulley next week and have been looking at the uprated larger diameter crank pulley but have read that they are very expensive £1400+vat and there is a overheat problem not sure if this is charge temps or lean fuelling even with a remap anybody had this work done or got advice

i do believe the cooling of the supercharger can be an issue as it's not far from the top of the operating temperature in standard form

Thanks i know there are uprated items so i will look for these thanks for your help

Out of curiosity what is a larger diameter crankshaft pulley supposed to achieve ?.

Cheers
Col

More power something to do with belt speed I believe but yet again stand to be corrected

Is that not the object of changing the S/C pulley to a smaller one so it spins up faster ?.

Cheers
Col

Yes change the pulley so the supercharger spins up quicker the same with the bottom one the issue is with the 2 pulley changes and a good remap you are looking at a reported power increase of
510bhp standard to 650bhp as I said that's quoted power increase but the independent range rover experts I use said even with a remap it could be on the limit of enough fuel being supplied

I think I would be more concerned about running out of transmission rather than fuel, as the 6HP28 Second Generation transmission fitted to the RRS1 S/C is rated at max. 700Nm of torque, I would imagine there is some built in tolerance on that.
What is the estimated torque to go with the 650bhp ? as when I had mine S/C pulley and Remap done the Dyno reading was 750Nm torque which I personally thought is as far as I will push my luck. I imagine the later SVR's etc. have the later 8 speed HP32 gearbox which I believe is rated at 800+Nm.

Cheers
Col

Last edited by Col on Fri Mar 30 2018 12:27pm. Edited 1 time in total

i agree with col dont think the box would take that much and i do think you would have cooling issues as well

3.0ltr SDv6 has 700nm of torque out of the dealership so there must be some tolerance built in otherwise there would be a lot more gearbox failures than we read about. 2020 Pangea Green 1st Edition D240 New Defender 110 is here and loving it
2018 Melting Silver Mini Countryman PHEV - soon to be replaced
2015MY Corris Grey SDv6 HSE Dynamic, the best car I have ever owned, totally reliable only a cou0le of rattles in 3 years, now no longer in my care
Also in my garage is a 1996 TDi300 Defender 90 County HT made into a fake CSW

But doesn't the SDV6 have the 8 speed 8HP70 Transmission ? hence rated at 700Nm. and SVR's possibly have the 8HP90 which is rated at 900Nm. but that is only a guess I imagine some the guy's that own SVR's would know which transmission they have. It would also appear the HP28 is rated at 650Nm. not 700 as I thought.




Cheers
Col

At the design stage all components have a Factor of Safety. The gearbox at a rough guess would have a FoS of 1.5 at least, probably 2. That means if it is rated at 700Nm it would take at least 1050Nm. For the majority of time you will never be near this unless your going racing

Hi guys
At my reckoning it would work out at around 750nm I understand what you are saying about the gearbox and I have spoken with different people about this issue and the consensus appears to be that if you use all this power at a set of lights your gearbox is dead within 2 weeks but if you use the power when rolling this would work to be fair I am only seriously looking at the upper pulley and remap because I think a 100bhp increase will be more than enough

To be fair I did have mine done 2/3 years ago and have not destroyed the transmission yet, and according to the Dyno readout after having it done it is throwing out 750Nm of torque well 749 to be exact. Not sure of the exact technical reason, but apparently due to the engine/transmission ecu's and how they communicate it is not possible to get a true bhp reading, however based on the graph reading they did get in their experience they would estimate it somewhere between 560 & 580bhp. As I said the bhp is only a guess/estimate which I think is the case in all these so called "gains" as with the exception of a few cases never seem to see the actual computer generated dyno readout's after they have been done in which case they could pick any figures out of the air.

Cheers
Col

Yeah can't agree with you more I am simply looking for that little bit more power and think this is the safest route can't wait to feel the difference