C70 D4(177) improve fuel eco-Remap and Alloy wheels downsize

[moneysh]

Hello everyone,
This is my first post in this forum, recently 'upgraded' to a 61 Reg C70 D4 from a back-breaking - firm and bouncy '12 Reg Merc C220. I'm excited about my new Volvo in all aspects especially the seats , suspension, power but a tad disappointed with Fuel consumption. Just to give a background, drove a 320I SE(Comfort suspension) for 4 years before I signed up for C220 only to get rid of it in less than a year!! So the C70 is reminding me of good old days with the Beamer but also unfortunately heavier on the wallet like my good old petrol 3 series.
Is it possible to remap my D4 177 bhp Geartronic into a more Eco(Fuel efficient) friendly mode or remapping is all about extra power?. I find the power /response on my C70 quite good however I'm struggling to breach the 40 mpg mark even on 70% motorway 30% B road drives(consistently hit 57 + on my C220 Blue Efficiency Auto on the same route )
Also I was considering to downgrade from my 18" Alloys to 16" to make the ride comfier(30% of my drive is on poorly maintained B-Roads) and extract any additional fuel economy. Kindly share your experiences even if it were with S40/V50/C30 if the above changes added any value.
Should I go for the OEM supplied 16" Castula Alloy Wheels (Silver Stone) for alloy wheels or are there any specific aftermarket one that someone would like to recommend?
Any experiences on the Insurance implications of remap and alloy wheel changes are welcome too.

[Proghound]

Going from what I've read on here, I'm not sure if you can get a D4 remapped, wasn't that the first of the ECU's that Volvo locked? Hopefully someone will be able to confirm. If so, that would restrict you to Volvo's own PoleStar map, which is expensive (~£800) and conservative at about +15hp. They market it as optimizing efficiency - guess that means you've got the choice to use the extra power or the economy. I hear that insurers have been known not to mind a remap of < 10% extra power, but it should be declared in any case. You'd have to check with yours.

Re the alloys, 17" are widely regarded to ride noticeably better than 18", but still look good. With the D4 you'll have the larger front brake discs, 17" will be fine but before you go for 16" it would be worth checking if they will fit over the calipers. Again I think I've read on here that the Castulas will be OK, but while IMHO aftermarket would look much better, that's when you'd need to check for clearance. Can't see the insurance having any issue if you downgrade your wheels within the Volvo range, but you might need to tell them about aftermarket.

Your 6-speed Geartronic on the D4 is a newer version of the 5-speed AW box they used with the D5. That certainly put a big dent in the economy compared to a manual, where 45MPG is easy. Even on the manual though, I notice quite a large drop in economy as soon as you get to 70mph (2K RPM). At 65, that's just over 1850 and it'll get 45-50 all day long. I would be interested to know what the gearing is like on the D4 auto, as it's one thing I would consider as a replacement for mine, should it get unecomic to maintain.

[domhart10]

Yeh I have changed down from 18 Volvo Midirs to 17 MSW as much lighter and a lot comfier ... defenitly recommend the changing down part.

My cars not very economical so I dont have anything else to add sorry ... maybe just pump your tires up a lot and drive slower

[DAN AT ADRIAN FLUX]

Hi,
If you need any help with insurance at all for either modification then please feel free to drop me a line.
Regards,
Dan.

[Welton]

Merc C220 has a poor ride?

That's the car I've shortlisted for my S40 replacement at some point.

Re: Tyres have a look in the owners handbook or the tyre pressure table (back of the fuel flap?) and see what tyre sizes are listed there. These are the volvo approved sizes so you won't have any insurance issues sticking with those.

[moneysh]

I can vouch for the fact that an 18" Volvo C70 ride is far far comfier than a 16" C220(W204) Executive - Blue efficiency. My 4 year old son and my wife could instantly remark that our good days are back- 2006 BMW (E90) SE !!
Having said that, the C220 was fine with five people and atleast 10% underinflation...it might be down to the fact that with Blue..eco thingy..the car has lost significant weight in all areas including wind shield, alloys, boot lid, engine..what not..but somehow the engineers in MB forgot to tune the suspension! The 2008-12 Elegance is much better choice...forget the > 2012 especially the Sport ones..

[moneysh]

Originally Posted by Proghound

Going from what I've read on here, I'm not sure if you can get a D4 remapped, wasn't that the first of the ECU's that Volvo locked? Hopefully someone will be able to confirm. If so, that would restrict you to Volvo's own PoleStar map, which is expensive (~£800) and conservative at about +15hp. They market it as optimizing efficiency - guess that means you've got the choice to use the extra power or the economy. I hear that insurers have been known not to mind a remap of < 10% extra power, but it should be declared in any case. You'd have to check with yours.

Re the alloys, 17" are widely regarded to ride noticeably better than 18", but still look good. With the D4 you'll have the larger front brake discs, 17" will be fine but before you go for 16" it would be worth checking if they will fit over the calipers. Again I think I've read on here that the Castulas will be OK, but while IMHO aftermarket would look much better, that's when you'd need to check for clearance. Can't see the insurance having any issue if you downgrade your wheels within the Volvo range, but you might need to tell them about aftermarket.

Your 6-speed Geartronic on the D4 is a newer version of the 5-speed AW box they used with the D5. That certainly put a big dent in the economy compared to a manual, where 45MPG is easy. Even on the manual though, I notice quite a large drop in economy as soon as you get to 70mph (2K RPM). At 65, that's just over 1850 and it'll get 45-50 all day long. I would be interested to know what the gearing is like on the D4 auto, as it's one thing I would consider as a replacement for mine, should it get unecomic to maintain.

Thanks a ton Proghound. You've pretty much clarified everything for me. Remap isn't worth if > £400 personally.

This site says 16" - 7.5j (instead of the regular 7j) is recommended for winter !!
http://www.wheel-size.com/size/volvo/c70/2011/
The castulas are £208 each!! Hence exploring aftermarket that sell for £400 a set. As you've said there are some really cool looking ones..Will drive into an Alloywheel place over the weekend and check the calipers' clearance.

Coming from C220 7 speed Auto gearbox...the D4 Geartronic is comparable(to the Sport mode rather than Eco) if not better..I even had one of my mate, who drives a 530d Auto, complement the seamless gear shifts in my D4.As you've rightly said, driving in the A roads < 70 I could hit 41.8, while the motorway alternative @ Cruise set at 80 mph pulls it down to 39!!This is where I miss my C220 - its nominal operating speed seems to 80 mph...only on stretches where I would exceed 85(shh...German Autobahns)..i could see the drop in economy!!

I generally under inflate the tyres by 5% to extract a softer ride..so that option to get a better economy is ruled out too!!