Lift arm spring

[hunterracing]

Can to soft spring cause loose drive outa corner or soon pick gas up say bottom spring out compressing almost 5 inch and what affects of goin up on spring rate 25 lbs at a time

[MasterSbilt_Racer]

Can to soft spring cause loose drive outa corner or soon pick gas up say bottom spring out compressing almost 5 inch and what affects of goin up on spring rate 25 lbs at a time

Too soft will keep the car from hooking up. Too stiff will cause the tires to shock loose. It takes some trial and error to see what works for you. Once you get close, 25# wont make a lot of difference.

[Matt49]

There is another often overlooked side-effect of too much 5th coil travel. And that is the fact that it raises your J-bar pinion mount point.
What MBRacer said is spot on but just something else to think about.

[hunterracing]

So if it's goin way to far travel it moving readend pinion up which is taken angle out and hurting the other factors with it correct? So goin up 25 lbs at a time won't be that big off affect especially if it's supper slick? Bcs like Masterbuiltchassis said I dnt wanna go to stiff and then shock the tires and not hook up either

[Matt49]

Could be helping...could be hurting...
Just be sure to understand that j-bar angle decreases as 5th coil travel increases.

[hunterracing]

But having one like but a 1inch bottom out is probly not good and hurting some drive up outa corner too tho correct? I think I measure almost 5 inches or should I not worry bout that

[a25rjr]

But having one like but a 1inch bottom out is probly not good and hurting some drive up outa corner too tho correct? I think I measure almost 5 inches or should I not worry bout that

A lot of it depends on track and driver. For instance, on a Smack car, my driver liked a stiffer spring in the first hole, while in a blue Rocket, he liked a softer spring moved forward.

You'll just have to experiment and see which gives you the drive youre looking for.

[hunterracing]

I jst figured travel was just alittle much I guess I was thinking only need be around 3 to 3 1/2 inches and if almost bottom out then it's really not applying pressure to the tires to the ground or am I thinking wrong

[a25rjr]

What spring are you using now? Mr. Wright told me one time, "I aint ever used anything stiffer than a 275"!

[hunterracing]

It's on a mod jst figured I get more help in this section then the mods and 175

[RCJ]

5 '' is alot of travel.The spring is a cushion to help keep the tires hooked.You are getting 5 inch of cushion before it starts applying weight to the tires(I know thats not 100% true just an example to help understand).I would go to a 275,With the bigger tires on a l/m you won't be as stiff as we are.I've filmed under the car and when you get to stiff it will lift off the r/r spring.3 to 31/2 is what I'm getting.

[keeks]

If the shock bottoms out you instantly create an effect of having a solid mount. This will take traction away right now. Go up in spring incrementally til you find the travel you're comfortable with. Try to do only the one change at a time(practice day), and log the results of each change so you have a reference to look back on. Can't have enough notes.

[Matt49]

Regarding how it changes j-bar angle, acceptable amount of travel is relative to position. 4 inches of travel at 39" out might not be a big deal. 4 inches of travel at 31" out could cause you some problems and inconsistencies.

[hunterracing]

I'm thinking of top of my head it's 34 inches or 35 out

[RacerX10]

Where are you measuring from to get the "out" distance on the 5th coil ?

[MasterSbilt_Racer]

Where are you measuring from to get the "out" distance on the 5th coil ?

center of axle

[hunterracing]

Yes center axle out