In Reply to: Question for 540i Owners Installing JC chip posted by daniel on April 01, 1999 at 12:03:58:
I just did the install following the instructions that came with the chip about two weeks ago. The top circuit board is connected to the lower board at one end via a flexible cable. The other end of the top board makes up the top part of the plug-in connection. You want to separate the two boards as far as possible at the cable end. First, there are two supports between the boards that you must release to allow the boards to separate. You should be able to figure out how by looking at the cable end corners of the board. Once separated to the maximum, you can slide the plug end of the upper board out of the plug connection assembly. This is not so easy to do the first time until you see the process. It took me about 30 minutes of careful wiggling, etc. until I mastered the trick. Once the upper board is free, the two boards can "opened like a book" by rotating the upper board over the top of the lower board with the flexible cable serving as a hinge. This will expose the chip which is covered with a white plastic shield that just snaps off.
The instructions with the chip are pretty good - just take your time.
I am very pleased with the results of installing the chip and recommend it strongly - the car seems more willing GO at all speeds - generally more aggressive throttle response, but I don't know about a big impact on low end "grunt". Part of that situation is due to the relatively high 2.81 (I think) rear end gearing in the '95 540iA. Several folks have installed lower rear end gearing and have been pleased with the results. I think 3.15 :: 1 has been a popular choice. BMW itself lowered the ratio in later cars.
Sharked & new short block
: I'm almost sure I will "shark" my 95 540i. One problem: I took the DME module out to make sure I didn't already have an aftermarket chip in. When I got the cover off I found two circuit boards forming a "sandwich" around the chip. How do you get at the chip without breaking something?
: I'm waiting to hear from bonneville motorworks, also, but would like to hear an owner's experience.
: Thanks in advance.
: By the way, is the performance increase noticeable? I find the 540i scary-fast, but would like a little more low-end punch.