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Ok thanks to our neighbor we have now weighed our car. If you don't know the details it's a 442 frame as far as I know with a Busa engine.
Wet weight:

Wet weight distribution:

With me in the car:


Sorry don't have a distribution pic for me being in the car. I'm sure if your building one of these cars you could figure it out. I'm relatively happy with these numbers as we are using proper seats. Sure our wheels are too heavy but staying with the affordable spirit of the car they were the best option. Now I want to buy a set of heavy duty home weigh scales so we can play with the cross weights a little bit.

Can anyone give me a rough idea how much adjusting the springs will have an affect?

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Deman Sr7 build turning laps once in a while

Adjusting the springs will have a large affect. For instance if you screwed down the RF spring ( imagine placing a brick under the tire ), you could almost get the car to balance on the LR / RF tires and have very little weight on the others.

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Maybe I'll try playing with them a bit tommorrow. I just don't want to leave the car on the scales all night. I would like to even out the distribution with me in the car a little bit. In order to do this I want the raise or wedge the left side and drop the right a bit right?

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Deman Sr7 build turning laps once in a while

It looks good without you in the car. I suppose it still looks good with a passenger near your weight.

How flat is the floor your measuring on? Do you have IRS? Getting in and out of the car may give weird results if the track changes a bit when the car goes up and down. If you could use ballast it might make the job a bit easier.

If you have something 1/8" thick for shims, you could experiment quicker at the beginning. Perhaps kitchen floor tiles or ? Changing the height of one corner will affect the diagonal corner too ( well all of them, I suppose ).

Honestly, I hesitate to guess, but maybe loosen the spring on the left rear just a little, maybe 1/8".

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Marcus Barrow - Car9 an open design community supported sports car for home builders!
SketchUp collection for LocostUSA: "Dream it, Build it, Drive it!"
Car9 Roadster information - models, drawings, resources etc.

Yeah I was actually quite surprised to see the empty weights not bad for an initial guesstimate reading. I'll play with them a little bit tomorrow just to see what happens.

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Deman Sr7 build turning laps once in a while

To properly corner weight a car all four scales need to be on the same PLANE. The plane itself can be tilted and it would have a large effect but this is critical... it will not work without this fact. I use a car lift. The process goes like this.... set ride height, set cross weight (lf+rr/rf+lr) to 50%... now your ride heights will be off. Repeat the process... there is a certain amount of chasing your tail required but this is the only way to do this. You can not change weight distribution by adjusting the preload... physics don't work that way.

No one else had a question after this??? I'm wondering as to how you figured this out, why it can only be done this way and perhaps a bit more extensive what you mean. I'm new and it seems when I solve one problem of getting around something I cannot do, another pops up, like car scales, car lifts, etc etc also how easy are all those adjustments made?

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I live in Illinois...Want an MK Indy R that will have around 200hp and 200ft/lb torq but have no idea which engine transmission to use.
Advice welcome here!

What part doesn't seem right?

If all four scales aren't on the same plane then one corner will be either compressed or extended more than the one diagonal to it. Since we are dealing with the spring rate and force (weight) at the contact patch, extending or compressing the spring will change the force.

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-Andrew
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I mainly ment using a car lift etc, I'm not sure many would have access to such equipment, at least I won't unless I'd visit a dealership, shop, etc. No friends with car lifts.

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I live in Illinois...Want an MK Indy R that will have around 200hp and 200ft/lb torq but have no idea which engine transmission to use.
Advice welcome here!

There are some techniques for working around the lack of a lift. A jack can be used to lift a specific corner, side or end for making adjustments.

If you are working without a way to roll the car at scale height to work the suspension out, then you might need to use one of the more common tricks for letting the wheels slide about. An old-school version is a couple pieces of flat sheet metal with enough grease placed between them to allow the plated to slide under the weight of the car. A newer version is to use 2 or 3 heavy duty trash bags to allow the tires to slide about. Either way you want to have a something under each wheel to provide for a way for the tires to slip around and let the suspension settle after each adjustment.

Just be sure to remove all the slip-gizmos before jacking the car up any distance; having the car slip off the jack would be bad.

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.. in the world

Another suggestion for corner wt.
When setting up for corner wt. mark the four floor locations for each leveling pad and how much of a shim pack is needed at that location right on the floor with a marker or paint. I also marked the shim packs with the corner location. The next time it will only take a few minutes to set -up the area to adjust the suspension.
Dave W