2017 740i xDrive vs 2016 750i xDrive

[GnatGoSplat]

I originally set out to look for a 2016 750i xDrive and even found the perfect car exactly how I would have ordered it new if I could have. It has 55K miles.

However, I'm concerned about the maintenance because it won't have a warranty. I am the warranty. I just have a regular home garage, no lift. Based on past cars (non-BMW), intake gaskets and starters are normal wear items. Starter is quite a task on the 750. Intake manifolds and gaskets are an even bigger task, almost engine-out. Of course, GDI, so intake valve cleaning is not an "if", but "when". Is it true on the 750, walnut blasting is engine-out? Granted, I haven't seen anyone mention yet of a N63TU2 in any car that's needed it.

Looking at the 740, the starter is pretty straight-forward. Intake manifold has a lot of tubes, hoses, clips, and harnesses to remove, but otherwise a DIYer can handle it. VANOS solenoids look to be harder than past-gen engines due to being in the rear, but looks DIY-able with the special tools. Definitely more DIY-friendly for sure.

I keep cars a long time, I'd say probably 10yrs minimum. I don't drive that much though, just under 7K/yr. If the potential 750 issues aren't likely to happen for at least a decade, then maybe I shouldn't worry about it.

I really wanted V8 for the power and sound, I thought it would be more fun. I don't care about fuel economy. Is the I6 noticeably slower and less fun? Can the I6 be modded to be as quick as the V8 without a complete teardown and rebuild? With the B58 being used in the smaller BMWs as well as Supra, does it have a pretty good modding community? I think 0-60 is 4.4s vs 5.2, is it even that noticeable? I've never driven anything as quick as either to be honest.

[dc5525]

I was looking at both 2018 740iX and 750ix back in March. I opted for the 740iX as I found it to be exact same car except for what is under the hood. The I6 is plenty powerful for me, mostly city driving (I only put 4k miles on car since March thanks to Covid19).

It was interesting the 750iX was only a little more expensive than the 740...but still opted for the 740. Love the car, plenty powerful for me!

[golobulus5]

Hey bud. I originally came from a 340i and needed a bigger car for the kids and bought a 740ix. The 340i has the same b58 engine and trans that the 740 has. The 340 guys are modding the crap out of these engines with great success. The engines and trans are good for between 6-650whp reliably, around 700 they get ringland failure. Around that power level something breaks in the trans too.
I like you when moving to the 7 series looked at the v8 TT, who doesn't like a v8 TT? I came to the same conclusion you did. Everything I have seen makes me think that this n63 is better than the old ones but still has problems. It didn't make sense to me to pay more for the v8 when I can reach my goals reliably with with the b58. It doesn't sounds like a v8 but I will give that up for reliability.

So here's what I have done so far. I took my dragy out and ran my car stock at 13.53@ 102 I did a stage 1 mhd 91 tune and ran it at 12.79@107.98. A few days later I ran the car with the 91 tune at 12.75 at 108.55 I then ran to the gas station and mixed to e30 and did the stage 1 mhd e30 tune and ran 12.35@ 111.3. This was a stock full weight car with 2 car seats on the street, tune only.

I was pretty pleased with these results. It showed me I made the right choice. I have more plans ahead. With a downpipe and stage 2 e30 tune I expect this car to be in the high 11's. After downpipe you can still get more power out of the stock turbo by doing a high pressure fuel pump. The HPFP is good for about another 50 hp.

So to sum it all up for this car you only really need 3 mods.
1. Downpipe
2. HPFP
3. Tune

Everything else really doesn't add power. The other cool thing is these mods are actually really easy to do DIY. The downpipe people say take 1.5 hours. The hpfp is on the top of the engine and easy to swap too. If you want more power there are a few different turbo's out that will get you to those 600+whp #s. Stock turbo people are hitting about 500whp with everything I mentioned and a custom tune.

A lot to take in and a long post. My suggestion is get that stage 1 tune and see what you think about it. Car felt great. 91 stage 1 is 360-370whp and 93 is 370-380. Great place to start.

[GnatGoSplat]

That's a great story, I was actually hoping someone would come along and post some actual numbers, so thanks so much! It makes me feel like a 740iX might be the smarter choice if I plan to keep it long-term. Google says the V8 does the 1/4 in 12.7, you're already at that level. That's pretty amazing for easy DIY mods.

What's disappointing though, is that in the color combo I want, I'm not finding very many well-equipped 740s. I'd really like the Autobahn package. It's rare enough, but extremely rare on 740s. 740s also have different lower-end headlights than 750s that I hadn't noticed before. Not sure if 740 could get the LED headlights, but I haven't found one with them yet. It's subtle enough I don't really care about that, but just an example of how differently equipped most 740s are. A lot of 740s also don't have the "comfort seats" that seem to be standard on 750s. Granted, I probably don't need all the options.

[TheManWithDa7]

750 is a piece of crap car.

[GnatGoSplat]

Originally Posted by TheManWithDa7

750 is a piece of crap car.

Details?

[pcrispy]

I have a 750i and the dealership loaners have always been 740i (I had the spark plugs replaced and the front grill motors were replaced under warranty). Anyone that thinks the 750i is junk in comparison has clearly never driven a 750. The 740i is good for a 6 cylinder when you floor it, but the results will leave you unimpressed once you're used to the results of flooring it in the 750.

[Lawguy]

Originally Posted by TheManWithDa7

750 is a piece of crap car.

I like a well reasoned opinion. 🙄

[wicked1044]

Originally Posted by TheManWithDa7

750 is a piece of crap car.

Cool story bro.