The Bentley shop manual specifies adding weights in the cabin to simulate driver and passenger, plus a couple of 6 packs in the boot when performing an alignment. The shop I have an alignment appointment with will add these weights for an additional $25, but indicates it's unlikely that I'll see any difference between the two scenarios.

Has anyone any personal experience to share on this?

Thx.

Alan
2005 MCS JCW

 

Don't worry about it unless you plan on actually driving around with that same weight in the car all the time.

 

I do recommend adding the weight of the driver in the driver's seat. Silly they charge extra for putting a couple weights in your seat.

- Andrew

 

If the six-packs are good stuff, $25 is not so bad.

I do it for corner-weighting (adjusting ride height) but not for alignment.

 

absolutely don't add weights . Waste of time.
Your alignment guy is right.No difference.

 

seriously? how do you figure? even if you weigh 150 lbs, you are affecting the ride height and thus the alignment.

it's not a huge deal, but it's also not a huge deal to throw some weights in the seat.

- drew

 

Seriously. Why would I post if I wasn't?
It's ridiculous to add weight to the Mini for alignment. I speak from years of experience here. Not just assuming.

 

okay. i speak from years of experience too. agree to disagree.

- andrew

 

Andyroo, it seems to me that if you had to have a weight comparable to the driver in the seat in order to get an accurate alignment that would mean every bump in the road would make the car out of alignment as it transitioned the bump. Doesn't seem logical.....

Also, what happens when you carry a pasenger? Does that throw the alignment off? How about something in the trunk? Or a couple of bikes on the roof?

I would agree with the corner weighting situation, or if you had a non-street alignment - something set up for racing or autocrossing, other wise I also don't see the point.

30 years experience here.....

 

Your alignment DOES change with every bump in the road!

It would really be amazing if the Mini, or any car for that matter, had it's wheels oriented the same exact way through out their range of motion. It would be an incredible handling car. This is why we add negative camber to cars for the static alignment....as the car rolls and/or the suspension compresses, things change and we lose negative camber. So adding some negative camber for your static ride height means when we start to lose it in roll or compression, we're still in a good place camber wise. It's also part of the reason why we stiffen suspensions for racing, less roll means less camber change (there are of course other reasons but this is a big part of it).

Alignment changes with ride height, period. Putting weight in the car changes ride height, period. The Mini is a light car on soft springs. A 200 lb dude is gonna make a difference.

I'm not saying it's a MUST do, or even that it's a HUGE difference, or that you're crazy not to or anything like that for a street alignment. But even though I'm skinny, I'm glad the shop I go to does it (for free) and no it's not ridiculous at all. And not much effort at all either.

- Andrew

 

Andrew,

Truly, respectfully, your facts are really not correct. Your thinking is somewhat logical, but not factual.

 

Please enlighten me with facts from your years of experience and prove to me that the Mini has zero bumpsteer and zero camber change under compression.

Again, I'm not saying adding ballast in the driver's seat is a must do, I'm just saying that things do change and there's no reason not to have a better and more accurate starting point.

Thanks.

- Andrew

 

I believe the BMW/MINI spec is for 200 LBS in the drivers seat.
I have not played with my Mini, but on most other (small and light) cars I have had, I do fill the tank to 3/4 full and add seat weight. It has made a measurable difference on some of them. It depends highly on the suspension geometry and springs. Cars with lots of camber/caster/bump-steer may change a lot more than a car with struts.
Practical on the road? I would not swear to that. Mini= stiff springs, strut fronts. Doubt a big difference, but why not?

Whenever Bilsteins get here, I WILL be playing with my alignment. Looks like the best de-camber in the front is a die grinder and serrated seat nuts.

 

Well, I will try.
True. But very very little in the Mini
Not so true. The Mini gains negative camber on compression in stock configuration, but yes, in hard hard compression it starts to then loose it to some small degree. Camber is also gained in turn in with the amount of castor that the mini uses.
But now you are talking camber and not alignment, witch is the adjustment of toe front and rear. Yes camber effects toe, but the addition of a body of close to 200 lbs has almost ZERO effect on the measurement. I used to think like you Andrew, but now I understand better as I have done this myself.
Big part? I would say that the use of selected spring rates to effectively change camber characteristics is only a secondary result of why we select them.
Anyway, this is becoming a silly debate. I never said that altering ride hieght does not effect alignment. I said that the effort of adding weight to "the Mini" during alignment is very not worth it.

 

What I took from your posts was that you should actually go out of your way not to add ballast to the drivers seat.

I should have stuck with the "things change" part of that paragraph and you are correct there from what I have gathered with regard to camber change on the Mini. I have seen this on the technical write-up on the Mini Mania PSA.

For me "alignment" as a term has always included camber and toe adjustment. Camber was used as an example but toe is my main concern for this. And although a small amount of toe in is gained under compression, I'd rather have a slightly better starting point.

Like I said, it may be a small difference, but for me it's also a very small effort of moving a few weights to get things just right. I'm not even the one moving the weights.

- Andrew

 

So what if driver wheighs say 325lbs and does about 7-10 track days a year. Should they put some weights for alignment?

 

No. They should lose some weight. Light is fast! J/K

 

Well, my Morgan had no change in alignment with travel. Sliding pillars, and a tie rod-drop link steering so no toe change either. NOT great handling, but I believe the first independent front suspension on a car ever. It actually had positive camber as it took it to keep it in a straight line. Many old card did. It cornered on old round skinny tire sidewalls. It had a solid axle out back. Again, ZERO alignment change with roll. A old Bug had pure trailing arms in the front. No camber change with roll. You WANT camber change to compensate for body roll hoping to keep the majority of the tire on the ground. We add static negative camber to the Mini because the strut suspension can't compensate as much as sporting driving requires.

The Mini has semi-trailing arm geometry in the back, sort of. This provides toe out and negative camber gain on bump, however the upper link is modifying it further so the exact result I am not sure.

Unequal length A-arms if properly designed, can provide quite a bit more control but it is all a set of compromises. There is no perfect suspension, or we would all have it.

I found my car sits a quarter inch lower on the drivers side than passenger. I will still put sand bags in it for alignment. Won't hurt. If nothing else, make me feel like I am being precise.

 

I don't weigh 325 but pushing 250 (I know..still need to lose weight) so when I have alignment done on my Mini I actually sit in the middle of the two front seats during alignment. Also 3/4 tank of gas.... unleaded of course to save weight

 

Sitting in the middle would seem to negate the goal of providing consistent alignment as the car is expected to sit on the road. My guess, mileage may vary.

 

Hummm. You may have a point. My theory is, by my weight being in the middle during alignment, would help off set the weight of passenger when I'm not the only one in the car, thus eliminating the need to put weight in passenger seat. Now my head hurts.