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Learning how to build Lotus Seven replicas...together!
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PostPosted: December 9, 2019, 6:45 pm 
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Put the tire compression back in and tweaked further. Notice zero camber but good compromise between roll (+1.828deg@3deg), rc height (2.638"), and bump (.699deg@1"):

default values

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PostPosted: December 10, 2019, 9:04 pm 
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I have looked into replacing my wheels with ones that don't need spacers. They have .945 in. offset, they are 9" wide same as my rears now. If I move the frame center to lower mount X out 1 in on each side and use my 15 in. Lwr A arms. This what I get.

https://tinyurl.com/suvj8mc

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PostPosted: December 11, 2019, 8:29 am 
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That is a huge improvement over you initial chart. Your in the ball park now imho so improvements are subtle but the swing arm length looks very short and the rc a bit high. The concern is jacking while cornering. You can still get good results with 90-100 swing and 2-3rc ht if you feel it is worth the changes.

I widened the chart to show what is going on out to six degrees roll. I tweaked what you have by eliminating the third digit since it would be more difficult to ensure accuracy in the build, brought the ride height back up, narrowed the track to 59 thinking the rear is 58, lowered and flattened the rc, and increased the swing arm to 93.

At this point, you might look at what is convenient as far as a uca that is long enough to clear everything and ucaps that don't stick out too far from the frame, then try to bring back the desired specs.

default values

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PostPosted: February 20, 2020, 2:54 pm 
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https://tinyurl.com/tav9d7b Vsusp link
I changed wheels and lengthened lower arms. New arms give me more adjustability . My roll center is down, not sure about what else
to look for.
Image

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PostPosted: February 20, 2020, 3:02 pm 
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The camber loss in 3 deg roll is much worse. I'd lower the ucap as needed to get back to a similar swing arm length and map both x and y for rc to try to keep it from moving so much.

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PostPosted: February 20, 2020, 3:57 pm 
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https://tinyurl.com/son6nrb

I lowered the upper arm pickup point. I'm not sure how to map both x and y for rc.

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PostPosted: February 20, 2020, 8:19 pm 
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Hold control to select more than one item to chart. Here it is with just the chart changed. The colors change when you change the chart:
022020Vsusp
Here it is tweaked a bit to keep the rc from moving and less camber loss in roll with static 1/2 deg neg:
022020Vsusp

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PostPosted: February 21, 2020, 12:24 pm 
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I want to thank you for all your help. This is the part of the build that I have been dreading.

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PostPosted: February 21, 2020, 5:34 pm 
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Your welcome. I enjoy tinkering with it. :)

Here is 1 deg neg on both to compare this latest tweak. The only difference between them is a ½ inch in ucap height and 0.05 inch further outboard. It results in more stable RC but higher, shorter SA, and less than ½ deg loss of camber through 3 deg roll.
022020Vsusp
Tweaked:
022020Vsusp
Note that we say level lca all the time but really it is a line drawn through the center of the lbj through the center of the lcap. Lca are seldom made made where the tubing falls on this line, more likely drooping to put the lbj and lcap at the same height.

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PostPosted: February 22, 2020, 1:52 pm 
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I went back and remeasured ever thing again and my spindle numbers were off. This is were I'm at now
https://tinyurl.com/qq666go

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PostPosted: February 22, 2020, 3:16 pm 
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Try this:
2222020Vsusp

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