95 540i - best bang for the buck

[Loppy]

Yes, I searched for an hour and nothing was specific to my general question. so please, help a newb out. Stoked I found the site, you guys kick ass.

Subject: I just picked up a 95 540i with sport seats, 6 speed manual. It was super clean and everything works, no issues. She idles smooth as glass. There is a little rumble between 2000-3000 rpm, but is smooth under and over that. I'm suspecting a vaccum leak, prolly the PCV. no big deal. she has 149K miles on her and it's been a California car all its life. I'm 3rd owner. Clean Carfax.

A. what problems should look for? what seems to be problematic on this car?

B. What performance mods would you do? I'm thinking cat back exhaust, airbox and chip. I want a little more go, yet keep reliability in tact.

Appreciate any input. Ive had an old 87 535 for years. This is a whole new ballgame!

[angrypancake]

welcome... thats a good find, post some pics!

[hakwuzhere]

Im not terribly technical... but do a search on Nikasil and Alusil.. that should be the first place to look... most people will also reccomend you have a leakdown test done (dunno what it is! but thats what I read!).

Oh, and pics.... TTIWWOP!

[BlueM60]

Congrats Loppy, Ive also got a 95 540i, mine is slushbox though, but I absolutely love the car. Like you said your in a different ballgame now with an E34 AND a V8. If you keep intake gaskets and valve cover gaskets on it, it will run for a long time and be leak free. Post some pics whenever you can. Ive got pics of mine but for some reason cant post them..
-Ben

[SRR2]

It's probably not worth getting all worked up about the Nikasil issue at this point. If the engine is running well, as yours seems to be, your car has dodged the bullet. The way to keep it that way is to make sure you use low sulfur gas. Good luck however trying to determine how much sulfur is in the gas available to you with the post Katrina revenue enhancement ^w^w formulation requirements relaxation program. There was a BMW program to replace nikasil engines with alusil but that's long since expired.

As far as a chip goes, there's not a whole lot of options there. The engine is already running close to optimum so there's not a lot of room for electronic tweaks. Do NOT mess with the airbox. Not one of the aftermarket suppliers of "cold air intakes" (which you already have) has ever shown certified, independent verification of any power increase.

IMO, if you'd like a bit more exhaust note, that's a reasonable thing to tackle.

You might want to change out the cabin air filter. Search for instructions on how to do that -- it's a bit of work. Chances are that yours is cruddy.

[onewhippedpuppy]

Congrats, the 540/6 is a sweet car, I should know. Don't worry about Nikasil, it runs well so you're probably ok. You already own it anyway, so it's too late to worry about it. Chip is really the only one that will gain you any HP, supposedly 15 or so. Lots of guys here like EAT, and they're a sponsor too. I have a Jim C, but it was in the car so I can't give you a before and after. Cat back will give you a nice sound, but no more power, and a intake is a waste of time. The only thing a K&N will give you is oil on your MAF, which you will then have to periodically clean. BMW's factory intakes are very good, and you really can't improve on them. Other than that, you seem to know about the PCV plate and intake gaskets, do the vac lines while you're under there. Shimmy at 55 or so is upper thrust arm bushings, a problem all E34s have. Check all your intake pipes for leaks and loose connections, that can throw off the idle. Also, cleaning the ICV, TB, and MAF is worthwhile.

[SRR2]

How is your 'chip' installed in your ECU? The older Motronics were easy with the socketed EPROM, and later ones could be programmed through the OBD port, except for the latest ones that require physical unsoldering of the ROM. Your car falls somewhere in the middle of the EPROM and OBDII type.

Do you have a link to actual before/after data on your ECU upgrade? Since the engine is already tuned for premium, how much room can there be for a programming only upgrade? Although Jim C is pretty credible. I had one of his upgrades in my '98 M-roadster and the effects were dramatic. That engine ran nominally on regular though and after the upgrade it required premium. That's why I'm wondering how much room there is for improvement when it's already tuned for premium.

[onewhippedpuppy]

Actually, it's tuned for 89. Here's a link to Jim C info, they're sold many places.

https://secure13.nexternal.com/share...t=products.asp

They show a gain of 19 HP and 33 lb ft. No dyno charts though. Give Mark D's EAT chips a chance first though, lots of guys seem to like his products better.

http://www.dsylva-tech.ca/

As for the chip, it's socketed. E34 540 is OBD 1, so we're just before the programmers. Should be a pretty quick mod, I had mine all apart to check my chip in under 10 minutes.

[632 Regal]

marks chip is a little more on edge and not taylored to every country in the world and you will get a bit more performance from them for your car.

[digitaldragon03]

The thing that bugs me about the Jim C chip is that the numbers are all wrong.

For the 540, he claims 19hp increase: Stock 282 / Chip 296 --- thats 14, not 19

Torque claim is 33 ft/lbs: Stock 277 / Chip 292 ---thats 15, not 33. Not only that, but stock torque is 295, where the heck did 277 come from? If the chip really does put out 292, the we lost 3 ft/lbs.

Seems odd to me.