[RoyB]

I have whatever spec was, I think 38 is accurate.

Mine came with the 21" wheels, sport seats, sun roof, etc so should be pretty much the same weight and driving dynamic as the competition. No spare, but I did put that fancy plug kit in the car. I weight about 220lbs and I had some other misc stuff like 2 cases of dog food and some clothes, etc.

I doubt there is much difference in unsprung weight with the smaller wheels since the overall heights are the same. I think I saw a post where someone weighed 20" snow setup vs 21 factory wheels and they were close to the same.

Either way this car is getting fun the more I get used to it. I had a 330i try to run me from a light today

[Max Well]

Originally Posted by RoyB

... Either way this car is getting fun the more I get used to it. I had a 330i try to run me from a light today

Bet that didn't turn out well for them.

I meant to add the stock acceleration curve from the Sim with my best ET, and I stitched in two high speed points I was able to get from BOGX4M's AutoTopNL video thread to complete the curve. Although it was X4MC, the Cd x A is close enough (0.36 x 2.69 vs 0.36 x 2.65) for a good approximation.

[crst4s]

Originally Posted by RoyB

I have whatever spec was, I think 38 is accurate.

Mine came with the 21" wheels, sport seats, sun roof, etc so should be pretty much the same weight and driving dynamic as the competition. No spare, but I did put that fancy plug kit in the car. I weight about 220lbs and I had some other misc stuff like 2 cases of dog food and some clothes, etc.

I doubt there is much difference in unsprung weight with the smaller wheels since the overall heights are the same. I think I saw a post where someone weighed 20" snow setup vs 21 factory wheels and they were close to the same.

Either way this car is getting fun the more I get used to it. I had a 330i try to run me from a light today

Car and Driver saw a significant decrease in 0 to 60 on their X3 M40i with a swap to smaller dia., lighter wheels. However, my X3M standard 20's with Pirelli Zeros weighed 67.6 and 71.6 lbs on a bathroom scale. This is actually heavier than the 21's with Contis as weighed by member RGSport (64.5 and 68.5 lbs). Wheel size apart, any performance difference between XM3 Comp and non-comp attributable to the extra top-end 30 hp is likely negligible compared to other variables such as track surface, track/tire/air temp, gas etc. Suffice it to say, both stock comp and non-comp X3Ms appear to be overachievers at the drag strip.

[Max Well]

Originally Posted by crst4s

Car and Driver saw a significant decrease in 0 to 60 on their X3 M40i with a swap to smaller dia., lighter wheels. However, my X3M standard 20's with Pirelli Zeros weighed 67.6 and 71.6 lbs on a bathroom scale. This is actually heavier than the 21's with Contis as weighed by member RGSport (64.5 and 68.5 lbs). Wheel size apart, any performance difference between XM3 Comp and non-comp attributable to the extra top-end 30 hp is likely negligible compared to other variables such as track surface, track/tire/air temp, gas etc. Suffice it to say, both stock comp and non-comp X3Ms appear to be overachievers at the drag strip.

Thanks for sharing, crst4s. Absolutely agree. And with my Sport+ Stoplight launches acting as a control for the DA differences between my Nov and Feb runs, I'm getting a sense that for this F97, at this Raceway (which has a smooth, prepared launch surface), it's coming down more to the tire-track interface. DAs were over 1000' apart yet the Sport+ results were nearly identical. The traction issue is something Drivers have discussed in the pre-staging lanes regardless of vehicle in my two days there, so right now that is my focus for improvement here. I need to dial in the right psi for this F97, at this track, to find that sweet spot. And then after that, my fourth day will be to change the octane. One step at a time.

BMW's engineering team did an amazing job with this one. Not sure why they underplayed the performance numbers as much as they have, but the end-result continues to bring a smile every time I drive one of our X3MCs.

[DasboostF80]

Max Well, I hope to begin adding data to your thread. My X3m Comp with sunroof is almost to break in, probably later this week. I just got my dragy as well. I am at sea level here and have 2 drag strips reasonably close. I hope to be able to test multiple suspension settings along with tire pressures on the way to finding the fastest 1/4mile time stock. Shortly after the mods will begin, primarily tune first.

Thanks for all the hard work you have done to start.

[SWOT1]

Originally Posted by Max Well

BMW's engineering team did an amazing job with this one. Not sure why they underplayed the performance numbers as much as they have, but the end-result continues to bring a smile every time I drive one of our X3MCs.

Pretty simple answer. BMW has always tried to maintain their series hierarchy, meaning the X5M must be faster than an X3M (at least according to official public numbers.) I think this works greatly in our favor as X3M/X4M owners, as we got some serious bang for the buck with this S58!!

[Max Well]

Originally Posted by SWOT1

Pretty simple answer. BMW has always tried to maintain their series hierarchy, meaning the X5M must be faster than an X3M (at least according to official public numbers.) I think this works greatly in our favor as X3M/X4M owners, as we got some serious bang for the buck with this S58!!

For sure. I've started to look at updating the Performance SAVs chart but realize this will be a difficult project to keep updated as the models (and data) change so much it's hard to keep track. And there isn't a central clearing house for confirmed data.

But, BMW indicates in their model release information the 2020 X5M and X6M (Comp models) are showing curb weights of 5425 and 5375 lbs., so with HP of 617 that yields Wt/HP ratios of 8.79 and 8.71. With our X3M and X4M Comp models showing real world dyno and 1/4 mile data suggesting 550 HP with weights of 4620 lbs., that yields ratios of roughly 8.38. So it'll be surprising to see those models perform better than the F97/98 editions. More plush and luxurious, no doubt.

But until we see some actual performance trials of these larger siblings, it's hard to know if BMW is undercutting their HP and torque values as well.

[AlexFL]

I think X5M/X6M are just as quick or even quicker, based on this new carwow video:

[DasboostF80]

This was from last night, temp was 38 degrees. I just filled the tank and it was full weight. Road isn't the best quality as I found traction issues all over the place. I was sport plus, sport suspension, D3 and mdm. The x3 had 900 miles and is in this morning for its breakin service. I think same road same conditions with launch control I could see bottom 12's.

[Max Well]

Originally Posted by AlexFL

I think X5M/X6M are just as quick or even quicker, based on this new carwow video.

So I spent some time today running the Sim for the F95 X5MC with it's stated 617HP and 553 lb-ft, Cd 0.38, A 3.0 and weight 5425 lbs. The curve falls below that of the F97 X3MC at our suspected real world values of 550 HP and 500 lb-ft stock. Not by a large amount, but enough you can see the separation, and at 88 sec the X3MC would be about 500 ft or so ahead of the X5MC.

Thinking BMW may have under-rated the F95 and F96 as well if those CarWow numbers are to be believed (we don't know the DA, octane rating, weight as tested, etc) but for the purpose of this discussion let's say they are what a regular production stock one would run in a formal drag strip setting, I then ran the Sim for 650HP and 600 lb-ft.

Bingo. The curves literally super-impose, such that at 88 sec the X5MC is only 30 ft or so in front of the X3MC.

So it'll be interesting to see the first dynos as they come out, and certainly to see some real world stock formal 1/4 mile times for these two new siblings to the F97 and F98, but I suspect 650HP and 600 lb-ft are going to be closer to what we find.

When I get some time I'll post the graph, but as the two curves lay literally on top of one another there isn't much to see.

Originally Posted by DasboostF80

This was from last night, temp was 38 degrees. I just filled the tank and it was full weight. Road isn't the best quality as I found traction issues all over the place. I was sport plus, sport suspension, D3 and mdm. The x3 had 900 miles and is in this morning for its breakin service. I think same road same conditions with launch control I could see bottom 12's.

Thanks for sharing. Although slope is 'invalid' (for what that's worth) and the curves aren't smooth, that is roughly what my two 1/4 mile times in Sport+ showed.

If you get a chance sometime on a fairly level stretch, I'd still be interested to see if my observation of faster time with Comfort/D1 over Sport/D2 holds up on repeated testing. Doesn't make sense to me that it should, and I only had two Sport runs and only one Comfort run with which to compare, so hardly a valid statistical comparison. Would just be interested to see some more runs with those two settings if someone gets a chance and wishes to try.

[DasboostF80]

Was only able to get one run in the morning. But the car is finally broken in, this was my first launch control attempt in the car. 46 degrees on a back road. These things are stout. Also sport + engine, sport plus suspension and traction off. I'll get some more runs in over the coming weeks trying different combos. Also it was full weight, almost a full tank and spare tire still in place.

[AlexFL]

Originally Posted by DasboostF80

Was only able to get one run in the morning. But the car is finally broken in, this was my first launch control attempt in the car. 46 degrees on a back road. These things are stout. Also sport + engine, sport plus suspension and traction off. I'll get some more runs in over the coming weeks trying different combos. Also it was full weight, almost a full tank and spare tire still in place.

Tire pressure?

[DasboostF80]

Fronts would have been roughly 34 rears at 37. This was a non scientific run more of a "I haven't launched this thing" let's see what it can do.

[AlexFL]

Originally Posted by DasboostF80

Fronts would have been roughly 34 rears at 37. This was a non scientific run more of a "I haven't launched this thing" let's see what it can do.

helluva time for a “non-scientific run”. Any mods planned?

[DasboostF80]

Originally Posted by AlexFL

helluva time for a “non-scientific run”. Any mods planned?

Yeah, probably bootmod3, If someone ever comes out with a mid pipe. I'm also interested to pull the intake off this thing and see what that looks like. I know eventuri is working on one. Picked this one up until the g80 come out but I am really loving this thing so far.

[AlexFL]

Originally Posted by DasboostF80

Yeah, probably bootmod3, If someone ever comes out with a mid pipe. I'm also interested to pull the intake off this thing and see what that looks like. I know eventuri is working on one. Picked this one up until the g80 come out but I am really loving this thing so far.

There are some catless midpipes already available. Eisenmann and SuperSprint already offer one.

[Max Well]

Originally Posted by DasboostF80

Was only able to get one run in the morning. But the car is finally broken in, this was my first launch control attempt in the car. 46 degrees on a back road. These things are stout. Also sport + engine, sport plus suspension and traction off. I'll get some more runs in over the coming weeks trying different combos. Also it was full weight, almost a full tank and spare tire still in place.

Thanks for sharing - looking forward to seeing more of your data in the future. The more we can collect, the better feel we'll have for what they can do across the board and not just in specific settings (atmospherics, locales, tires, road-tires, psi...).

[AlexFL]

For comparison, here are two more X5MC 0-62 mph runs. Based on those runs, the new X5M does not seem to be significantly quicker than X3MC. This is somewhat consistent with the carwow X6MC 0-60 result of 3.5 sec.

[r33_RGSport]

Originally Posted by AlexFL

For comparison, here are two more X5M 0-62 mph runs. Based on those runs, the new X5M does not seem to be significantly quicker than X3M. This is somewhat consistent with the carwow X6M 0-60 result of 3.5 sec.

Wow, that revvs sounds nice.

[AlexFL]

Originally Posted by r33_RGSport

Wow, that revvs sounds nice.

Sounds same as M5, no?

[r33_RGSport]

Originally Posted by AlexFL

Sounds same as M5, no?

No, this one have higher pitch. Or maybe just the video.

[chrisbrown44]

Where do post questions about my 2005 BMW X3?