05-13-2021, 09:08 PM | #1 |
New Member
16
Rep 25
Posts |
Can you feel turbo on M50i
The X5 M50 is my first turbo and have a (stupid?) question. Are you supposed to feel the turbos kick in? I kept it in 2nd gear from about 1000rmp to redline and did the same thing in 3rd gear. I just felt constant acceleration, but no boost.
I had it in the dealer the last few days because they had to replace the steering rack which involved dropping the suspension, getting a realignment, etc. I took it for a spin after. Believe me it's still fast, but I swear I could feel more of a boost when accelerating before I took it in. Maybe it's just my imagination. Is there any way to test if the turbos are acting normal?? |
05-14-2021, 10:57 AM | #2 |
Banned
429
Rep 756
Posts |
The turbos are there and active. "Kick in" was what many turbocharged engines did in the past or at least gave that general feel as a result of what is know as turbo lag. This has been eliminated to a great extent if not totally on some engines.
Be glad that you don't need to wait for them to "kick in". I have a relatively new '21 M50i and can tell you that the power delivery from this engine is absolutely stunning in stock form. Of course many of us always look for more. I'm ready to try the JB4 as there are no available flash tunes for the '21s until it is unlocked or whatever. |
Appreciate
0
|
05-16-2021, 10:10 AM | #5 |
Banned
429
Rep 756
Posts |
I had an old 300ZX Turbo back in the day that would lag terribly and then "kick in" like the old four barrel carburetor with mechanical secondaries would do.
|
Appreciate
0
|
05-22-2021, 12:35 AM | #7 |
Major General
3191
Rep 6,846
Posts |
Today's turbos are smaller with less inertia, and the intake and exhaust valves are specially configured to bring the turbos up to speed quite fast and at a low RPM. If you look at the torque curve, it builds at a fairly low RPM, and is much flatter than turbos of old that took awhile to come up to speed, then kicked you in the butt. This makes handling and efficiency better since things are smoother.
|
Appreciate
0
|
06-10-2021, 08:50 PM | #8 |
Brigadier General
3684
Rep 3,479
Posts |
OP does have a point. I have a highly modified twin turbo 3000GT VR-4 that has a half second turbo lag when accelerating, where it kicks in and snaps your neck with power.
I guess it hadn't crossed my mind, but yes, my M50i has almost instant power. The changes you guys are talking about must be really well done to eliminate this lag.
__________________
Cross-continent road trip journal from BMW PCD to Alaska in new X7 M50i in this thread HERE!
New EVEN BIGGER road trip in X5 from BMW PCD to Alaska NOW ONGOING LIVE IN THIS THREAD! Wilderness road trip journal to Eastern Alaska in this thread And road trip journal to Denali and the Arctic Circle here in this thread! |
Appreciate
0
|
06-11-2021, 10:29 PM | #9 | |
Captain
338
Rep 842
Posts |
Quote:
__________________
2021 G05 X5 ///M50i / Phytonic Blue / Cognac Vernasca
iStep 03/2023.50 |
|
Appreciate
1
Wild Blue3683.50 |
06-13-2021, 07:28 AM | #11 | |
Banned
429
Rep 756
Posts |
Quote:
Fast forward to 2021, take a BMW X5 M50i for a spin, turbo lag nonexistent. I gave up on the Asian tin cans 25 years ago, don't know if they have solved the turbo lag problem in their vehicles or not. The Germans seem to have nailed it. These engineering solutions shouldn't be that difficult for Hyundai, Kia, Subaru, and the like to copy. |
|
Appreciate
0
|
10-14-2021, 10:51 PM | #12 |
Private First Class
91
Rep 159
Posts |
Ya, the design of these turbo engines was specifically done to reduce any sort of turbo lag. The "hot-V" design almost all but eliminates any pre-turbo exhaust tubing. The turbos are basically bolted to the exhaust ports (on top of the engine) with 2-3" of total tubing between the exhaust ports and turbo inlet.
Because of the small volume of exhaust piping pre-turbo, this helps spool up the turbos very quickly. This is basically the best way to design a turbo engine if no lag is your goal |
Appreciate
0
|
10-18-2021, 09:19 PM | #13 | |
Enlisted Member
21
Rep 38
Posts |
Quote:
|
|
Appreciate
0
|
10-19-2021, 05:58 PM | #14 |
Private First Class
65
Rep 118
Posts |
I had a 2002 WRX, the lag in that was something else. I currently drive an Ascent while I wait for my X5M50i to arrive. That has almost no lag at all. Turbo tech has come such a long way the past 20-30 years.
|
Appreciate
0
|
10-20-2021, 12:45 PM | #15 |
Private First Class
1254
Rep 132
Posts |
Twin-scrolls, variable geometry, better/shorter manifolds, etc., mean that modern turbo-charged engines are much more tractable than they once were. My '82 Saab 900 Turbo was a blast to drive in Colorado's mountains, but you did have to learn how to drive it w/o getting hit by the rather massive turbo lag. The M50i? Really can't notice it at all.
|
Appreciate
0
|
11-12-2021, 08:50 AM | #16 | |
Enlisted Member
7
Rep 47
Posts |
Quote:
|
|
Appreciate
0
|
Post Reply |
Bookmarks |
|
|