6th Coil Travel

[TheJet-09]

I don't recall seeing it discussed much, but what are some averages you might see on 6th coil travel? I know there are many variables (all the track and driver differences), but when I ran a 2.5" spring (400#) I would typically see around 1/2-3/4". I should point out that I also have the old/bad driving habit of dumping the throttle and stabbing the brake (especially when there is traction available)...

But my current reason for asking is that, if I have my lift bar set-up properly in my car (2017 Lazer), my center to center on the fifth coil shock is 19" (only allowing me another 1" of travel under decel/rebound). Does that sound acceptable, or should I be concerned I might fully extend the shock?

As always, thanks in advance!

[Jking24]

That doesn't seem right to me. If the shock tops out during braking the rate goes infinite and could result in premature shearing of the car during braking especially with your admitted brake habits

[95shaw]

What would a shock extension hurt in this instance?

Just curious.

[ZERO25]

I don't recall seeing it discussed much, but what are some averages you might see on 6th coil travel? I know there are many variables (all the track and driver differences), but when I ran a 2.5" spring (400#) I would typically see around 1/2-3/4". I should point out that I also have the old/bad driving habit of dumping the throttle and stabbing the brake (especially when there is traction available)...

But my current reason for asking is that, if I have my lift bar set-up properly in my car (2017 Lazer), my center to center on the fifth coil shock is 19" (only allowing me another 1" of travel under decel/rebound). Does that sound acceptable, or should I be concerned I might fully extend the shock?

As always, thanks in advance!

Put the car in its dynamic state and see if it tops out!

[TheJet-09]

Looking at it in the opposite direction (no pun intended) I did consider a shock extension (maybe 1"), assuming I don't need more than 3.5-4" of compression. But I also wonder if ZERO25 has the answer, thinking that the 5th coil might actually compress some (or not extend, maybe stay near static length) even when the 6th coil compresses?

A small "helper" spring on the LF used to be the norm (to keep the spring seated during droop), but did or does anyone run one on the 5th coil as well?

Thanks for the responses!

[billetbirdcage]

Looking at it in the opposite direction (no pun intended) I did consider a shock extension (maybe 1"), assuming I don't need more than 3.5-4" of compression. But I also wonder if ZERO25 has the answer, thinking that the 5th coil might actually compress some (or not extend, maybe stay near static length) even when the 6th coil compresses?

A small "helper" spring on the LF used to be the norm (to keep the spring seated during droop), but did or does anyone run one on the 5th coil as well?

Thanks for the responses!

1' is too little, that I can tell you for fact it will top out (most cars) when the car is hiked and your on the brakes. Data acquisition found that one for me or I wouldn't have noticed it. They sent the wrong shock as it had a 6" shaft and the person that installed it didn't notice. We was testing and I was quick looking over the data and noticed a flat line in the rebound on 5th coil, it would only do it when car was fully hiked.

Think about it the 5th shock is behind the chain a far ways and when the car hikes it pulls the shaft out with no pinion movement (No on gas or on brakes).

Yes, some run a helper spring or a good lock on nut.

[billetbirdcage]

https://i.imgur.com/f46vzWQ.png

[08racing]

TheJet-09 I also run a Lazer and the setup book says to set your 5th coil static (ride height) c-c to 18.5”. Can you get another 1/2”? I used an extended upper shock mount to get that distance and keep my lift bar at the correct location. Pinion angle can easily be adjusted independent of the lift bar angle. This will give you enough extension travel. I never have a problem with the rear end breaking loose on decel.

I do have a helper spring on the 5th coil as well. I had a 5th coil spring pop off of the lower spring cup once and get stuck on the step of the spring cup. That adds 3/8” preload instantly on compression.

PM me if you want to talk about setups. Brandon and Jim are also very helpful if you call the shop.

Zach

[TheJet-09]

I missed the c-c spec but set the lift bar at the same angle as the frame rail (and upper shock mount assembly). I picked the car up at the end of last year, and have yet to run it, but I will certainly PM you with some questions.

[TheJet-09]

I noticed that from ride height (whatever that is anymore) to full droop on the LR, the 5th coil loses roughly 1/2" of pre-load. With that in mind, are guys setting pre-load when the car is at its static height (ride height), or more so in race trim?

Just curious. Thanks!