Company Details

I bought the kit as the air flow sensor had failed on my 2006 registered Rover 75 Tourer. I should have considered it sooner as it certainly has given the car improved power and driveability. It is easy to fit and I consider it to be a worthwhile purchase.

Excellent product that does exactly as advertised.. Getting much more power an torque as well as improved fuel economy. Really quick delivery as well..

Great little gadget easy to fit and made my VRS fly !!

This company can be trusted to buy from I’ve had some great results.

Superb products that really do work, excellent after sales support. If I need to tune a vehicle they'll be the first company I contact!

Well what can I say I'm over the moon Iv a mg zt cdti with a 160 map with a maf delete with other mods I wanted more power so brought a synergy 1 from rover Ron what a difference the car went well beforehand but with the Ron box on its a absolute animal Iv got the bug and I want more, the box is amazing postage was very quick (1 day within ordering) well made and quality comes with all instructions the after care/advise is one of the best Ron comes across as a sound bloke and gives really good advice even if like me your asking alot of questions on how to go further advise anyone who is on the fence about a Ron box then grab one especially with a 160 map makes a big heavy mg zt barge go like a small nippy hatchback, If your reading this Ron then thanks for pushing the boundaries my friend absolutely amazing bit of kit for very little money

Had a Synergy/Ronbox for over 4 years and they have just re-cabled it for my new car.....superb product and service, Thanks

Ive had many range rover p38 diesel over the years and every one ive paid £200+ for a re-map but got to say this synergy 4 ronbox is in a league of its own without a doubt worth every penny my 2001 range rover p38 diesel was doing 20mpg as stated in the manual and top speed of around 90-95mph soon as I fitted the ronbox was advised to keep it on number 2 for now and wow what an amazing piece of equipment mpg has shot up to 30-32mpg on the motorway and 27-28mpg round town top speed so far is 115-118mph and the performance is incredible Dont waste money on expensive remapping these guys know what there talking about and there synergy 4 ronbox is the business thanks guys will deffo recommend to others

very helpful good products and prices

Excellent, recommend tuning-diesels to anyone.

I received my Synergy 1 box yesterday, fitted it today (10 minutes, if that, including siting, connection and cabling). Incredible difference, tried it on 5, cranked it up to 7 and it seriously is astonishing. The 220 cdi engine is great and probably the best diesel engine I have experienced, add the Synergy box and it feels like it is now what it should have been, initial turbo lag is barely noticeable, power is smooth and linear to 110+.It has transformed a gorgeous, torque packed cruiser into something way more. Probably the best £90 I have spent in 10-15 years.

Absolutely top rated. The Synergy literally transformed my 2.0di Freelander. Easy to install fantastic performance improvement. Support is second to none: swift response and corrected an ordering error (on my part) free of charge. 100% recommended!!

Very good contact and service. perfect !

Excellent price of kit for the money, company was excellent and trustworthy.

Excellent service when I called for advice and the product is awesome

had box for rover 75. got new one for 2.2 xtrail good power and throttle response

Great advice, fast delivery, easy to fit. Car transformed. What more could you ask for.

I bought the Synergy 2 unit for my 2.2d X-Type Jag and found that it was very easy to install. Unfortunately I could not really detect any improvement in performance or more importantly MPG. So I returned the unit and received a full refund. Since then I have had to have the EGR valve replaced on the Jag , so this may explain why the Synergy unit had little effect. So in summary if you fancy trying this device then even if your not convinced, rest assured you will get a full refund.

3 years ago I had a “Synergy 2a” installed in my lovely Rover 75 CDTI. It totally transformed the excellent BMW Diesel engine: increased torque, BHP & fuel consumption. I’ve just had fitted to our Fiat 3 litre Ducarto Motorhome a “Synergy 3” & am expecting exactly the same brilliant transformation. We heartily recommend ‘Tuning Diesels’ products. PRB

Freelander 2 This is the second box still having great results on my td5 110. Freelander 2 b0x is working great ,only just fitted it so early days . Great firm would recomend