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View Full Version : LF Bump stop?



Kromulous
03-21-2023, 09:08 AM
Not sure if anyone will share any info on it or not, but whats it do ? I see them a lot nowadays.

I would think its so you could run a softer spring to help get the Car to steer, but then not fall off a cliff if you get out of the Gas real quick but i never ran one to know.

MasterSbilt_Racer
03-21-2023, 01:20 PM
Not sure if anyone will share any info on it or not, but whats it do ? I see them a lot nowadays.

I would think its so you could run a softer spring to help get the Car to steer, but then not fall off a cliff if you get out of the Gas real quick but i never ran one to know.

It's about having two different rates and a reliable stopping point. Reasons can include wanting a soft spring to aid weight transfer upon acceleration, soft rate on initial turn-in as you suggested, or probably quite a few other uses. It can actually be easier to tune entry with one, IMO, especially where you slow a lot before entering the corner.

Kromulous
03-22-2023, 08:53 AM
Soft spring to aid weight transfer upon acceleration. Hmm thats interesting, i need to study on that i guess.

I guess i need to get one on and start tinkering with it LOL.

MasterSbilt_Racer
03-22-2023, 10:34 AM
Soft spring to aid weight transfer upon acceleration. Hmm thats interesting, i need to study on that i guess.

I guess i need to get one on and start tinkering with it LOL.

I'd say the weight transfer deal would not be a modern use. Back in the leaf and early 4 bar days, guys would run dual rate across the front to have a light rebound rate for maximum weight transfer. You could drag race like nobodies business. Entry was another story...

JustAddDirt
03-28-2023, 08:41 AM
Back in 2018 i played a bit with 5" X11" springs 250-275# left front 225# RF on a chevelle clip modified.
had a bump stops on both front shocks.
at lawrenceburg it would coil bind the RF because of the waves, woop sections in the track.

95shaw
04-01-2023, 07:11 PM
Soft spring to aid weight transfer upon acceleration. Hmm thats interesting, i need to study on that i guess.

I guess i need to get one on and start tinkering with it LOL.

It is still the same as the left rear, using a soft spring maintains more weight on the tire for the same amount of travel.

100# spring

600# load.

Unload 200#. Spring is 2 inches longer than at ride height.

600# spring

600# load

Unload 200#. Spring is .333 inches longer than at ride height.

For a given travel, softer spring maintains more load.

For a given unload, softer spring travels farther.

Raising the center of gravity is generally synonomous with weight transfer.

Kromulous
04-03-2023, 01:31 PM
So your saying in simple terms that the LF Spring can retain some weight longer with the lighter spring, makes since.

A 275 and 225, thats crazy.

outlaw4j
04-04-2023, 01:19 PM
after watchinq a few usmts races this year i think they might have the bump stops on the LF to act as litteral bump stops. a lot of them dropping pretty hard onto the LF on entry