The Lotus Cars Community banner

1 - 20 of 26 Posts

·
Registered
Joined
·
282 Posts
Discussion Starter #1
Hi,

My tires should be here tomorrow, I'm planning on taking the wheels to the tire shop.
I have the jack helper, this will be the first time using it.
I'd rather not have to remove the shear panel under the car. Did that twice already for oil and transmission fluid change. No fun putting it back.

1: Get car on 4 ramps (for more vertical clearance for subsequent steps)
2: Raise rear of car with Jack Helper, place 2 stands under Jack Helper, remove jack.
3: Raise side of car at A, just slightly, and slide jack stand under B. Repeat for other side.

Photos below are not of my car.

Thanks,

1263631
1263632
 

·
Registered
2005 Lotus Elise
Joined
·
54 Posts
I would probably jack up one side of the car from jack point A, place jackstand under lift point B, place ramp under rear tire. Repeat on the other side.
Then use the jack helper to get the ramps out from underneath the rear wheels and then support the jack helper on both sides with two jackstands.
I'd make sure they are the flat pad stands though
 

·
Premium Member
Joined
·
1,333 Posts
These are fantastic to add to your car: MWR Lift Point Kit - Lotus Elise/Exige/2-eleven

I jack at Point A on one side of the car then place a jack stand at Point B and on the MWR Lift points. Next I jack the other side of the car the same and place jack stands at the same points. What is nice about MWR Lift points is that you can lift the car on a 2 Post Lift without removing anything.

Later,
Eldon
 

·
Premium Member
Joined
·
591 Posts
I would do #3 before #2 and don't forget to loosen the lug nuts before you lift the car off the ground.
I do it much the same way, I lift one side at A and put block of wood under wheels, then the other side the same, then remove the belly pan and the lift each side to fit the jack stands under B and C.
 

·
Registered
Joined
·
282 Posts
Discussion Starter #5
I would probably jack up one side of the car from jack point A, place jackstand under lift point B, place ramp under rear tire. Repeat on the other side.
Then use the jack helper to get the ramps out from underneath the rear wheels and then support the jack helper on both sides with two jackstands.
I'd make sure they are the flat pad stands though

Simpler and better than my plan.
Thanks!!
 

·
Premium Member
Joined
·
591 Posts
Simpler and better than my plan.
Thanks!!
Depending on the height of your jack stands, I would be careful doing it in one lift, I know with mine I wouldn't feel safe.
 

·
Addict
2007 Lotus Exige S
Joined
·
1,404 Posts
I think you'll be fine with the method above. A second set of rims come in real handy for this too.
 

·
Registered
Joined
·
4,407 Posts
These are fantastic to add to your car: MWR Lift Point Kit - Lotus Elise/Exige/2-eleven

I jack at Point A on one side of the car then place a jack stand at Point B and on the MWR Lift points. Next I jack the other side of the car the same and place jack stands at the same points. What is nice about MWR Lift points is that you can lift the car on a 2 Post Lift without removing anything.

Later,
Eldon
I'm also a huge advocate of the MWR lift points with lift, but I am always leery of using a floor jack with them since that puts a decent lever arm on them that could bend the chassis. Note, I said leery and not that I avoid doing it. It just makes me squeamish. What are your thoughts? Am I being paranoid or careful?
 

·
Premium Member
Joined
·
591 Posts
Unless you have the car pretty much level, I wouldn't trust those MWR extensions. Each to their own, but I value mine and the cars safety a lot more than the extra time it takes to do it right.
 

·
Premium Member
Joined
·
1,333 Posts
I'm also a huge advocate of the MWR lift points with lift, but I am always leery of using a floor jack with them since that puts a decent lever arm on them that could bend the chassis. Note, I said leery and not that I avoid doing it. It just makes me squeamish. What are your thoughts? Am I being paranoid or careful?
I didn't say put a floor jack on them. I only put a jack stand under them. They explicity state on them that they are not to be used with a jack. I would not want to side load the pin while trying to use it to jack the car.

Later,
Eldon
 

·
Premium Member
Joined
·
1,333 Posts
Unless you have the car pretty much level, I wouldn't trust those MWR extensions. Each to their own, but I value mine and the cars safety a lot more than the extra time it takes to do it right.
At the track, I will jack the car up using Point A. Put two jack stands under the car. Go to the other side and jack at Point A again. Two more jack stands added. They look to pretty stout but I would not want to put the jack motion on the pin. I feel that would cause a pulling/jerking effect at the bottom of the pin.

Later,
Eldon
 

·
Premium Member
Joined
·
591 Posts
My jack stands are 15" tall in their lowest setting, to me that would be too much of an angle for the jack and the stands as well, I would be afraid something would slip, and end up with a big mess. 🤣
 

·
Registered
Joined
·
4,407 Posts
I didn't say put a floor jack on them. I only put a jack stand under them. They explicity state on them that they are not to be used with a jack. I would not want to side load the pin while trying to use it to jack the car.

Later,
Eldon
Now that I think about it, that's also what I do rather than jacking the lift point directly. That being said, the side load on the pin is nearly the same whether it is being held up by a jack stand or a jack, the only difference being the little bit of extra load the front jack stand carries when doing as you said.
 

·
Premium Member
Joined
·
1,333 Posts
Now that I think about it, that's also what I do rather than jacking the lift point directly. That being said, the side load on the pin is nearly the same whether it is being held up by a jack stand or a jack, the only difference being the little bit of extra load the front jack stand carries when doing as you said.
If you have ever actually watched a floor jack move and the extra pressure that is created when the floor jack needs to roll as it lifts because the car won't, I think you would better understand my point. Every time you push the handle down, it creates an extreme amount of side loading on the pin. If the pin is just sitting with a side load as the other side of the car is jacked, it does not create the same loading effect. In fact, the more you lift, the less side load that is created. I have seen floor jacks not want to rool as they lift and literally move a 3/16" lip under a lifting edge then try to fall of the jack. Or watch a floor jack go on two wheels because it cannot roll because of how the mechanics is designed. That is what they are afraid of happening with the pin.

Later,
Eldon
 

·
Registered
Joined
·
4,407 Posts
If you have ever actually watched a floor jack move and the extra pressure that is created when the floor jack needs to roll as it lifts because the car won't, I think you would better understand my point. Every time you push the handle down, it creates an extreme amount of side loading on the pin. If the pin is just sitting with a side load as the other side of the car is jacked, it does not create the same loading effect. In fact, the more you lift, the less side load that is created. I have seen floor jacks not want to rool as they lift and literally move a 3/16" lip under a lifting edge then try to fall of the jack. Or watch a floor jack go on two wheels because it cannot roll because of how the mechanics is designed. That is what they are afraid of happening with the pin.

Later,
Eldon
Yeah, I have observed all of that firsthand which is why a floor jack should always be aimed towards the centerline and the floor should be free of debris to allow for it to roll freely. Those are not the side forces they are worried about, I'm positive. The much larger side force (or rather, moment) is what happens as an angle is created between the pin and the lift point. Check out my fancy diagram:

1263677


See how this does create torque on the pin regardless of the lifting technique? The higher you lift one side of the car, the more torque is placed on that pin. Yes, poorly roll flooring jack wheels will make it worse, but proper car should always be taken to avoid that with any floor jack regardless.
 

·
Premium Member
Joined
·
1,333 Posts
Yeah, I have observed all of that firsthand which is why a floor jack should always be aimed towards the centerline and the floor should be free of debris to allow for it to roll freely. Those are not the side forces they are worried about, I'm positive. The much larger side force (or rather, moment) is what happens as an angle is created between the pin and the lift point. Check out my fancy diagram:

View attachment 1263677

See how this does create torque on the pin regardless of the lifting technique? The higher you lift one side of the car, the more torque is placed on that pin. Yes, poorly roll flooring jack wheels will make it worse, but proper car should always be taken to avoid that with any floor jack regardless.
I agree with your diagram and the torque that is going to be applied as the pin is not loaded entirely axially. If the bolt stays tight and the base of the pin stays flush, it should be able to take the load. You have access to FEA software, run the calculations and let us know. All I'm saying is that a jerking motion at the bottom of the pin is considerably worse than a constant side loading force. If this method is a major concern then lift the car using Point A and place jack stands under Points B & C. Lift the other side at Point A and jack stand at Point B and MWR. Then lift at Point A on the other side again and move the jack stand to the MWR lift point. This way you are keeping the load almost entirely axially. From this point, you can R&R the undertrays.

Later,
Eldon
 

·
Registered
Joined
·
289 Posts
If in doubt...why not just do 2 trips and bring 2 wheel/tires at a time without leaving your car in the air. unless you live very far from a tire shop.
 

·
Premium Member
2005 Elise LSS Saffron Yellow
Joined
·
814 Posts
I would probably jack up one side of the car from jack point A, place jackstand under lift point B, place ramp under rear tire. Repeat on the other side.
Then use the jack helper to get the ramps out from underneath the rear wheels and then support the jack helper on both sides with two jackstands.
I'd make sure they are the flat pad stands though
This is pretty much what I do. It works fine, but is a lot of little steps. I don't use the MWR lift posts, so drop the undertray when it's on the ramps, then jack up a little more on one side from jack point A and set a stand and block under lift point C on that side, then remove the ramp. Repeat on the other side.
 

·
Registered
Joined
·
4,407 Posts
I agree with your diagram and the torque that is going to be applied as the pin is not loaded entirely axially. If the bolt stays tight and the base of the pin stays flush, it should be able to take the load. You have access to FEA software, run the calculations and let us know. All I'm saying is that a jerking motion at the bottom of the pin is considerably worse than a constant side loading force.

Later,
Eldon
My concern is that the chassis designers never intended for the first lb-ft of torque on that very thin-walled chassis box. A great example is how you can stand on a flimsy coke can as long as the sides don't buckle. As soon as you shift your weight so as to apply an uneven load, it crushes. Similary, boxes don't take torque well at all - ever see a square driveshaft? Keeping the plates well-torqued like you point out though effectively reinforces that chassis box, and I think that is sufficient. Having done lifted it myself without breaking anything, evidence agrees, too.

Regarding FEA (and CFD for that matter), I'm sure you've heard the addage "garbage in, garbage out". Without knowing the strength of the chassis adhesive, the directional effects of extruding the aluminum, etc, any analysis would have a huge range of possible answers. In the presence of test data, even this FEA guy will bow out.

To be clear, too, the only reason I went down this rabbit hole with you was because I thought we were talking about the same thing at first! Not trying to pick at anything, just took some effort to clear up exactly what was being said. Funny how differently two people can see the same problem. I will still disagree though about the jerkiness of the jack wheels being scary. Material-wise, you're not going to introduce a fast enough strain rate to the chassis to be considered "dynamic", and, having succeeded with lifting it directly by the jack without causing damage, it seems we have sufficient safety factor. To reiterate though, I only did that at first and have since stuck with your approach because I do think it is safer, however small the difference is.
 

·
Registered
Joined
·
282 Posts
Discussion Starter #20
This is pretty much what I do. It works fine, but is a lot of little steps. I don't use the MWR lift posts, so drop the undertray when it's on the ramps, then jack up a little more on one side from jack point A and set a stand and block under lift point C on that side, then remove the ramp. Repeat on the other side.
Is removing the undertray a hassle? To me, the shear panel IS a hassle. So many bolts, and putting it back on is tedious. My back let me know about it afterwards, Lol.
 
1 - 20 of 26 Posts
Top