A disclaimer before I begin….I am not associated with ESS Tuning. I also am not associated with Dinan and I do have their products on another car and love them. I also realize that the 4.6is in its stock form makes more than enough power than one could ever need. And to answer some people’s question of why didn’t I just get an M5, well the M5 is a great car without a doubt, even owned a 2000 for about six months, but wanted something different and the X5 fit the bill for me.
When I traded in my 01 4.4SP with Dinan Throttle Body and Software installed, I vowed that I would not make any modifications to the 4.6is. After almost a year of ownership I began hearing rumblings that Dinan was coming out with performance modifications for the 4.6is. I called Dinan and my rep told me about the parts that were available now: CAI, MAF, Intake Manifold, Throttle Body, Exhaust, and Engine/Transmission software. The expected gains were about 30-40HP. He had no pricing available but I researched those same parts for a E39 540 and came up with a cost of around $5000.00 plus the labor to install. Had the Dinan rep not mentioned the upcoming supercharger I would have done these modifications. The supercharger peaked my interest. The 4.4 kit was just around the corner but the 4.6is kit wouldn’t be here until Spring 2003. I also referred to an E39 540 for pricing of the kit and it was $15,999.00 plus installation. Because the supercharger had peaked my interest I started doing some research on other tuners. I contacted ESS Tuning and they had 4.4 kits already on the market and had done a Euro spec 4.6is in Norway. They were willing and ready to try a U.S. spec 4.6is. Their kit was about $8300.00 plus installation. After some more research I found out they they use the same Vortec supercharger as Dinan but they do their own programming and plumbing. After some lengthy calls with Richard who runs their U.S. office and Hans in their headquarters in Norway I was ready to go. One week later my kit arrived. The kit was complete and the workmanship looked good. The Vortec unit is perfect. The main bracket holding the supercharger is CNC machined and very solid. The plumbing of air intakes is good. By this I mean they are very clean and functional. This is one area where Dinan has manufactured carbon fiber pieces which look nicer. They function the same though. There were a couple insignificant hiccups just due to the U.S. spec car being different from the euro spec one. Nothing major. My BMW tech took 3 days to install which is about one day longer than ESS claims it should. One thing ESS was lacking was a “proper” installation manual. The one provided was in beta format and left a lot to be desired. It would have been somewhat difficult for a DIY to do. Even my master mechanic had some difficulty understanding where this goes and what this does, etc. Under normal circumstances, in a production kit, ESS will send out a complete kit to you. Before you begin the install, you need to remove your ECU and MAF and overnight them to ESS for reprogramming. They can do this in a day and overnight back. In the meantime you are installing the kit. Realistically figure 4 days before you are back on the road. In my case, since the 4.6is was somewhat an unknown, they had an ESS tech from Norway here on site doing the programming. It’s pretty cool “James Bond” like stuff he does with the electronics. He spends about 4-5 hours road testing the vehicle with a laptop attached all the while adjusting fuel curves, etc. ESS prefers not to tune cars on a dyno as they are really an artificial environment. They prefer real world road testing.
Ess has programmed the car with 7lbs of boost and left the rev limiter in its factory setting. They had reprogrammed the trans software to slightly lower rpms as the shift points arrive as to minimize strain on the transmission. The tech mentioned that the 4.4 trans is well built and even with the 392HP it puts out, the transmission can handle it. In his words, I beat the s-h-i-t out of the 4.4 for a year and the transmission is fine.
Now to the fun stuff. The car is a beast. He claims that the 4.6is should be putting out over 450HP! It has all the drivability of a normally aspirated vehicle but when you apply throttle the power is right there! There is a slight SC whine and the CAI on the SC gives a awesome full throttle sound. No lag like what I have experienced in previous turbo based cars. The car is unbelievable. Lots of torque. I can’t say enough about it and I am totally happy. I am trying to find a 4 wheel dyno to run the car as well as taking it to the strip for some 1/4 mile times.
Miscellaneous stuff. For those of you that are planning to do a CAI on your X5, do not if your are doing a SC. The SC uses a different CAI configuration. Those of you planning on doing the naturally aspirated mods to your X5, either the 4.4 or 4.6is, you might want to look at the supercharger. I think it offers better value for the horsepower. For those of you with a 4.4 and are thinking of a SC, do it. I can only imagine that having 392 HP is just as good as having 450HP or so. For the money, I probably would have been just as happy supercharging my 01 4.4SP and could have saved some money over the 4.6is. Also, the 4.4 kit is in the process of getting its CARB certification and the 4.6is is coming next.
The ESS guys are very professional. I had hesitations dealing with a company based in Norway but the experience has been all good. The ESS guys are also some of the brightest software techs around. They claim that there are 7 top software techs in the world that know BMW programming codes. ESS has two of them. Another 4 work for top Euro tuners, and the seventh works for Dinan. He did say that Dinan was the only U.S. tuner that knew what they were doing with software tuning.
ESS fully tests all their vehicles (BMW and Mercedes). The 4.4 was tested for over a year for durability and longevity. On a side note, it took ESS 3000 hours to develop the base software program for the 4.6is. The tech confirmed that the 4.6is engine is an Alpina engine and that they have had that engine running in Europe for over three years now. Apparently that engine has been fitted to BMW cars as well. They are fortunate that in Europe, they get availability to new cars about a year before we see them here in the States. That is why they will have kits outs before any US tuners.
In summary, I am very happy with my decision to go with ESS. They are very knowledgeable and extremely professional. They know their stuff! If price were equal, it would be very hard to choose between ESS and Dinan. That says a lot because I place very high regard upon Dinan products. To date, I have about 200 miles on the car with no issues. Time will tell about the reliability of this unit but I am optimistic that there will be no issues. The SC unit requires no maintenance and is self oiling via the factory oil system. The SC drive belt needs replacing after 50,000 miles and the K&N CAI filter gets washed every 25,000 miles. Inspection I & II’s can be performed with no removal of this SC kit. Hope this is helpful to all…..Also for reference, here’s an article on the Dinan S3 4.6is Supercharger Kit