x5 - how often need to change spark plugs if at all?

[X5SilverBeast]

Originally Posted by FSETH

This is where we differ. If I wanted more power, but still like the e39 body, I would sell your 540 and buy an e39 M5 before I ever even thought about doing as LS swap. I am sure you can almost get an M5 with the sale of your 540 and the additional savings of $10,000+/- from the cost of the LS swap. Not to mention the resale value on that LS swapped 540 would be garbage unless you found just the right buyer. Plus, I would much rather have the s62 M engine than an LS any day and there are plenty of tuning options for that motor.

I see your point and actually considered doing so before the LS swap came to light. Very true as far as tuning options. That has really upset me that the M62 doesn't have very many options to squeeze out HP for a decent price. I've been all over BFC and M5Board and noticed the S62 has a little more maint. items to worry about over the m62(also mine is prevanos and the 97/98 came with the bigger intake over the vanos m62tu). I'm not worried about selling the 540 with an LS swap due to the fact I'll probably end up keeping the car for a long time. But for a stock M5, say 400hp, with high mileage or low mileage, I could probably do the ls swap for around the same price.(Not sure as I haven't priced out the e39 m5 lately.) Also, with few bolt-on mods, I can push a lot more HP with the LS motor for a lot cheaper than the S62. Cams are cheap on an LS compared to the S62. I've also considered FI just like m5james. But with adding FI, I've always been under the impression with high mileage engines, you may want to rebuild the internals to take the added boost. which is an additional cost.

I'm def. not worried about the resale value of the car. That pretty much took a dive over the past few years. When I bought the 540, paid like 13K and NADA was at 18K. Now you can buy any e39 other than an M5 for like 3K or more. I totally get where you are coming from, but the bond I have with my car now, makes me wanna keep it for a long time. Plus, you don't see very many e39 with an LS motor. It's like frankenstein on steriods. lol