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Installing the Superchip Performance Chip in Your RoverLast winter I received one of the Superchip performance kits. I installed it for evaluation purposes in my personal 1997 Range Rover 4.0SE. It’s an otherwise stock truck with 140,000 miles on the odometer. I drove it 7,500 miles on the Superchip for this article.The Superchip upgrade discussed here is available from Rovers North for 1995-1999 Range Rovers with GEMS engine management, 1996-1999 Discovery I models, and 1997 Defenders. A chip upgrade for newer Rovers is in final test and will be available soon — look for updates in my columns later this season. Robison Service installs the full range of Superchip products. I was always looking for a little more zip from the 4.0 engine. This chip provided it. Installation was easy, and I saw immediate benefits. There is a noticeable improvement in takeoff response and midrange power. The 4.0 now drives much like a 4.6. The truck is generally quite a bit more responsive. I've had several other 4.0 drivers try my Rover, and they have had the same reaction. I would recommend this upgrade for anyone looking for a little more power from their Rover. How does the Superchip get more power from the motor? I talked for quite a while with the folks at Superchip about this very thing. American Rover engine controls are programmed to tolerate poor fuel, poor upkeep, and poor driving habits. They do this with very conservative programming of the engine management. The Superchip programming takes out a lot of that slop. You get more power but it becomes much more important not to neglect your Rover's care and feeding. They use more timing advance, which gets more power but you have to be sure you only run premium. They deliver more fuel on initial takeoff, but it's vital that you stay on top of oil services because engine loads are higher. They have made many small adjustments to fuel delivery and ignition that add up to (according to them) nearly a 10% improvement in power at most speeds. I expected gas mileage to decline if power went up, but that did not happen. Over two long tests (5,000 mile) my fuel economy remained within 0.4MPG, sometimes being better, other times worse. I conclude that the power gains are got by increased efficiency, not by increased fuel consumption. In cold weather I noticed a different idle behavior. I noticed a faster idle when cold. Otherwise there was no difference in how the truck started or ran. The Superchip system is less forgiving of wear in other system components. For example, the Superchip ECU gave faults on my truck for slow o2 sensors. The standard ECU showed no o2 faults. On a manual test, I found the sensors were near the end of their service life, so I replaced them. After that the Superchip ECU was fine. My point here is that when you install a performance chip it may show up other weaknesses in your system, and you should be prepared to deal with that. Don't just assume there is a chip problem if you get a check engine fault right after you put the Superchip in. To install the chip, you remove the GEMS ECU and take off the cover. You should do this work on a (conductive) metal table and wear an anti-static lead to avoid damage. On the circuit board you will see the EPROM covered by a plastic cap. Remove the cap and remove the chip, and fit the new chip. Be very careful fitting the chip — it's easy to bend the pins, and if you install it backwards you could damage both the chip and the ECU. Once the chip is fitted and the ECU is assembled and fitted into the car you will need to use a Testbook, Autologic, or Rovacomm system to reset the security interface between the engine ECU and the security system. The truck will not run until this is done — so if you don't have the ability to perform this step — don't start!! Call Rovers North for the name of the nearest shop equipped to do the installation for you.
In the remainder of this month's column I have answered some questions at greater length than I was able to on the bulletin board:
Where can I get service information for my Rover online?
If you need specific repair information you should be aware that Land
Rover has established an official site, www.landrovertechinfo.com
where you can obtain all the factory service documentation for your vehicle
at moderate cost. They offer daily, monthly, and annual subscriptions
starting just over $25. It's a real bargain for full access to the factory
archives. This site is limited to US market Rovers from 1987 to the present
day. Here are some of the things you can access:
The Land Rover site was established in conformance with new Federal laws
requiring them to provide everyone (not just dealers) full access to all
service materials. You can find similar sites for other car makes here,
at the directory of the National
Auto Service Task Force.
What do I have to do to install one of the inexpensive new short blocks
in my older Rover? I am speaking here about a 1995 or older Rover with
the 14CUX fuel injection. The cylinder heads should have a valve job whenever they are off, in my opinion. I suggest you surface the heads .020 and use the later model head gaskets (they are thicker.) When you install the heads you will note that the lowest row of head bolts is no longer used. Rover found that those bolts caused uneven stress and they deleted them from the block. You should use the newer intake and valve cover gaskets from Rover. The newer rubber parts are less likely to leak. Also don't forget to use new cylinder head bolts. The bolts stretch on installation; they are not meant to be re-used. They sometimes break when used twice, necessitating time consuming tear down. Be sure you use the timing cover gasket that matches the cover actually fitted to your engine. The covers have oil passage holes in different places — fit the wrong gasket and your oil pump may never prime. The oil pans are sealed to these newer blocks with sealant, not a gasket. Land Rover and we recommend a product called The Right Stuff from Permatex. It's expensive, at near $15 a tube, but very effective. The less expensive RTV sealants sold in consumer auto parts stores are much less effective and in some cases don't work at all on oil pans. I highly recommend Right Stuff. You will need a spacer at the end of the crank pulley because the end of the crankshaft on the newer motors is longer. Robison Service can supply the spacers, or you can make one locally.
Is there a vibration problem with the newer engines?
Consequently, if you fit a new short block to an older truck you may notice a different vibration or a different “feel” to the engine. The differences I have observed have been most noticeable from 1,200 to 1,800 RPM. Most owners of automatic transmission Rovers will not notice this difference. It is more noticeable in standard shift trucks. It's not a terrible problem — it's simply a difference someone attuned to their car may pick up on.
I've been told my Rover engine has a dropped liner. What does that
mean? With time the movement allows coolant to begin leaking from the passages that surround the liner over the top of the liner and into the cylinder. When that happens you get coolant coming out the exhaust, and exhaust gases may pressurize the cooling system excessively and cause overheating. I have seen some trucks with knocking and loose liners run 20-30,000 miles without coolant failure, while others fail right away. The most common liners to drop are those for the two driver-side rear cylinders. The only cure for this problem is a new short block. Land Rover has dropped the price of replacement short blocks (see my winter column) in response to increased dropped liner complaints. Dropped liner failures are often associated with overheating incidents — either because they caused the incident or because the overheating caused the liner to come loose. As a result, you should take any overheat or near-overheat situation very seriously. Never drive for long periods with a clogged cooling system and the needle near the red. Never drive at all when the gauge is in the red. Not even for a mile to get off a highway. The price of neglecting this rule could be a your motor.
Is it true that a coil sprung Rover rides more gently than an air sprung
Rover? And if so, why? An air spring is, as the name implies, filled with air. The more you compress it, the harder it gets to push because the air is more and more compressed. If you have an air spring that's six inches tall, and you compress it to three inches, you will have doubled the pressure within and doubled the force needed to compress it farther. So if it takes 200 pounds to compress it one inch it might take 600 to compress two inches and 1000 to compress three inches. A steel coil, in comparison, would usually be more linear, taking 200 pounds to compress one inch, 400 two inches, and 600 three inches. You can see from the above example how a jolt is felt more sharply with the air springs. The steel coil springs fitted to Range Rovers are fairly soft and fairly tall. Therefore, they can soak up a good-sized bump. In highway mode the air springs have much less ability to soak up a big bump, and the difference is really noticeable.
Should I be using Dex-Cool antifreeze in my new Rover in view of the
problems I've heard about? We believe in using the manufacturer-specified fluids in most cases. Dex-Cool and traditional green coolant are both ethylene glycol based, but the additive packages are different. Test results are inconclusive — you may have cooling system trouble if you switch. Therefore, if you have a Rover that was factory filled with Dex-Cool we suggest you stick with it. But to be safe we suggest changing the coolant every two years regardless of mileage, or every 30,000 miles, whichever comes first. Coolant manufacturers have told us you are much less likely to have cooling system trouble if your system is kept full. That means making sure your expansion tank is always kept topped off to the full mark. The coolant needs some space to expand, so the tank can't be filled to the brim. There is risk of coolant deterioration if the tank goes empty and the level in the radiator drops. Another thing that can cause trouble is low pressure. You get low pressure when your system has a leak or when the cap fails. When your truck is running make sure the hoses feel hard with pressure. If they feel soft, you may have a pressure problem. Readers with questions can contact me at robison@robisonservice.com I try and answer emails individually but I can't always answer them all. I put the most interesting in my columns.
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