Spring angle

[Hagen14t]

Hey guys, ive got a quick question. My car has four holes for the right rear spring to be able to tip it in and out at the top. What are the effects of tipping the spring in and out at the top? What would be a good angle to start at? And how to i measure the angle? Ive never had a car with multiple holes for this option and i was just wondering what the effects are. Thanks for any input.

[oldtrackchamp4x]

Once again,always call your chassis builder first. He should be able to tell you all you need to know about your car. jmo.

[RW57]

We are building my son a new car and I built this feature in to it. It is a stock clip 2x 2 car on swing arms that are clamped as it is a 3 link car with a solid top link. M y thinking on this is as you lean the springs in it will have the same effect as going to a softer spring as Ithink the rate will soften as the spring is leaned in . The springs are also angled foward about 15 degrees on it also . Just my opinion I really hope this will allow us to really fine tune the car. I am also setting the rear up so that the eliminators and shocks can be flipped flopped from front to rear in any combination shock on swing arm eliminator behind rear end any combo we want. I have also set it up to run a 30 in panhard or a 20 in j bar from the left or right side hope this helps. We are a low buck outfit as he goes to school 4 hrs a day and works basically full time to support his habit so we have to try to out think or out smart the competition lol.

[Graff Spee]

In the ultra quick and simple answer, it would be more angle = less efective.

[racin6mod]

By moving the top of the spring inword you are softening the spring rate a little and possibly helping with any binding the spring might be having under bodyroll.

[Hagen14t]

So under what track conditions would you want to do this on? At what angle would it be overkill?

[Hagen14t]

Please anyone?

[washeduptoo]

Dry slick, angled in at top will add side bite is what I think according to Mark Bush article in mod mag. New car will have that option and going to try it.Good luck.

[clm15]

Two things going on. A short panhard bar/ J-Bar pull the rearend to the left under bodyroll. So the Lr spring is unloading. ( Not alot but with more hike it is noticable) Look at some photos and the left rears on some cars is out of the body. Pullbar cars show the most. The fast latemodels mount there j-bar in line with the spring on the frame mount,and set the angle of the spring to follow the ark of the J-Bar. Makes sence when you think of it.
The other is when the birdcage indexes into the Lr spring. Mount the top back so when the spring indexes it pushes the spring strait into it self.

Think of this. When a piston and rod get to top dead center the crank goes from left to right,the piston stays at top dead center. this is dwell time. There is a hole lot of movment of the crank and nothing happening with the piston. Make sure the birdcage and the spring have no dwell time.

[sj valley dave]

What do you mean that the late models mount their j bar in line with the frame mount of the shock?

[clm15]

What do you mean that the late models mount their j bar in line with the frame mount of the shock?

I knew this would be confused! sorry about that. From looking at the left rear shock and spring,from the back of the car,the J-bar mount on the frame,(Whare the hiem joint bolts) Is in the middle of the spring.
The spring is mounted so it moves at the same rake as the J-bar.

[sj valley dave]

That would only work if you are running the spring/shock in front of the axle. We run our spring/shock behind the axle on the "hook' and the J bar is in front of the axle so they are not on the same plane form left to right...

[clm15]

No the spring is behind with the shock ahead. Mark Bush pointed this out at his seminar. You get a chance look at the left rear of a Rocket latemodel. I think you will see what I am saying. I looked for a photo but cant find one.

[sj valley dave]

LOL If your talking about a DLM, most guys run the spring and shock behind axle...some guys will run a pop up or traction shock in front also. Our car loses forward drive with a pop up in front...Almost all GRT's just run shock/spring behind...We use a BSB aluminum frame mount for the J bar that has an arc so you don't get your rearend side to side location screwed up when you change you J bar angle...Don't know much about mods, enjoy watching them, always have worked on Late Models...