[Ryephile]

Originally Posted by F1FTY

Thank you!

How did you determine the spring travel? What formula? Curious because I didn't know that could also be calculated from this!

There's no complicated formula, just some subtraction and division. I can't determine total spring stroke from free to block, only make assumptions. I just looked at the linear part of the graph for each. For the front it's linear from roughly 325 Lbf to 875 Lbf, which is (875-325)= 550 Lbf of range. 550 Lbf /178 Lb/In = 3.1". The spring has to compress for more than that because there needs to be preload for the correct ride height (roughly 1000 pounds each front corner means there's probably 2+" of preload to get 4" of droop, seeing the early spring rate is much lower), plus the entire damper travel is roughly 6", so the spring rate is only linear for less than half of the springs compressibility. Essentially the spring is only linear from slightly above ride height to full bumpstop compression.

[F1FTY]

Originally Posted by Ryephile

There's no complicated formula, just some subtraction and division. I can't determine total spring stroke from free to block, only make assumptions. I just looked at the linear part of the graph for each. For the front it's linear from roughly 325 Lbf to 875 Lbf, which is (875-325)= 550 Lbf of range. 550 Lbf /178 Lb/In = 3.1". The spring has to compress for more than that because there needs to be preload for the correct ride height (roughly 1000 pounds each front corner means there's probably 2+" of preload to get 4" of droop, seeing the early spring rate is much lower), plus the entire damper travel is roughly 6", so the spring rate is only linear for less than half of the springs compressibility. Essentially the spring is only linear from slightly above ride height to full bumpstop compression.

excellent, thank you!

[RideZX6R]

So what specs are we missing to be able to go to a spring manufacturer and ask to have a set of springs built that are 1LE spring rates with drop of approx 1in all around?

[Cupahaters]

So are we saying lowering the car and adding 1le package is a bad idea?

[F1FTY]

Originally Posted by Cupahaters

So are we saying lowering the car and adding 1le package is a bad idea?

Not necessarily bad. Doubt any mechanical damage occurs, but no aftermarket lowering spring out there right now has an improvement in spring rate over the 1LE factory springs.

[PolynesianPowerhouse]

amazing job you've done on this.... most people just buy springs according to "amount projected to lower" and have no clue about the other factors that will determine overall lowering amount as well as performance.


btw, where did you go to get the springs teched out?

[F1FTY]

Originally Posted by PolynesianPowerhouse

amazing job you've done on this.... most people just buy springs according to "amount projected to lower" and have no clue about the other factors that will determine overall lowering amount as well as performance.


btw, where did you go to get the springs teched out?

Thank you! This thread reminded me that I still need to have the SS springs tested for comparison charts.

RRT Tuning in Dulles is where I got the test done. Great group of guys there that race BMWs.

[crankaholic]

This is an awesome thread!

I have my stock set of FE3 springs in a box... I'll try to find a place that can measure springs rates around here and will post results if I do. If I'll have some extra $ at the time, I might ask them to take off my Eibachs and measure those as well - always good to have independent numbers.

[F1FTY]

Originally Posted by crankaholic

This is an awesome thread!

I have my stock set of FE3 springs in a box... I'll try to find a place that can measure springs rates around here and will post results if I do. If I'll have some extra $ at the time, I might ask them to take off my Eibachs and measure those as well - always good to have independent numbers.

That would definitely be a huge help! I have my SS springs boxed up.

Might buy some BMR and Phastek springs for testing but that's out of pocket and I'd rather not upset the vendors that wish for their rates to remain proprietary.

[Rinker]

Originally Posted by F1FTY

That would definitely be a huge help! I have my SS springs boxed up.

Might buy some BMR and Phastek springs for testing but that's out of pocket and I'd rather not upset the vendors that wish for their rates to remain proprietary.

So If I'm understanding this correctly...Replacing my 1LE springs would be a mistake.

Don't see how that'd be out of pocket, simply trying to make an informed buying decision. In the event that their product is superior to others, that would only help that said company, as well as create competition amongst other companies to make a better product.

[F1FTY]

Originally Posted by Rinker

So If I'm understanding this correctly...Replacing my 1LE springs would be a mistake.

Don't see how that'd be out of pocket, simply trying to make an informed buying decision. In the event that their product is superior to others, that would only help that said company, as well as create competition amongst other companies to make a better product.

For performance at this time, yes.

It would cost me out of pocket to buy all those other springs and have them tested. I could get it done for under a grand, but I don't like you guys quite that much

[glenB]

Need to make this a sticky if you plan on updating

[F1FTY]

Originally Posted by glenB

Need to make this a sticky if you plan on updating

Yeah that would be easier. Maybe a mod could help us out?

[RideZX6R]

Has this been updated since the Eibach 1LE specific lowering springs have launched?