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New to mods so I have a question.
Was running pure stock for a few years and was a camaro so I am not used to having so many adjustments.
What does Raising the J bar at either end do?
Moving J bar at Pinion ?
Moving J bar at Frame ?
Pull bar is 36 inch long. What does the angle actually do ?
This is a 3 link setup. Limited modified. Just curiuous so It may be a quicker learning process for me. If I have a head start will be easier.
ty in advance.
In short.... Raising the J bar at the chassis side will give you more sidebite. The more angle in the pull bar the quicker it hooks up, the less angle, the longer it stays hooked up.
What does adjusting the j bar at the pinion do? I have 5 holes there and it is 1 above the pinion level?
Just the opposite.. Ususally run at pinion level or lower
Go to the GRT website under set up help they have some charts that will help with adjustments.A problem i had when I came out of camaros to mods was when you change one thing you have to reset everything else.Set the car to the baseline setting then cut some pieces of pipe that will just slide between the lower a-arm and the frame,on the rear cut them to go betwween the axle tube and the frame.These pieces of pipe will let you reset your ride hieght quickly.Get a piece of string 2 foot long tie a 1/2'' nut on each end.Hang the string over the left rear frame rail above the rear end measure from the pull bar mount to the string.Write this number down every time you change the j-bar you need to readjust the the length back to this number.with the rear steer set slide the string to were it just touches the axle tube,weld a small tab to the frame exactly were the string was on the left and right frame rails.This will let you reset the rear steer quickly by throwing the string on the tab and adjusting the trailing arms till it touches.
it realy changes the rear rollcenter of the chassis usually once you have found the best location on the pinion you won't be changing it at the track very often. normally you'll adjust it at the frame mount 1 inch up or down is a good size adjustement.you can buy frame mounts that have an arch built in the to keep from adjusting the j-bar length every time you move if at the frame.measure from the ground to the center of each hiem joint you should stay between 3'' and 5'' of rack or the differance between the two lower at the pinion.Quote:
Originally Posted by BCR
OK so I have spent alot of time researching all sorts of sites and looking through archives here.
This is what I have learned.
Amount of rake is usaully between 3-5 inches higher on frame side.
The more rake you have the more weight or bite is transfered to the rear.
affects entry and mid turn.
most of your adjustments are made on the frame side.
moving the pinion side is used to adjust rear roll center ( here is my next question )
really sorry !!!
what does the rear roll center affect ? higher from the ground I would think the car would not roll over to the right rear as much ??
Lower to the ground the car rolls over easier ?
true/false ?
If your center of gravity is 18'' high and your r/c is 8'' it like turning a 10'' long ratchett wrench.If you drop the the roll r/c to 4'' it's like switching to a 14'' long ratchett.The increased leverage makes the car act as if it has softer springs in the rear.When you get on the short straight bars they react different and it is trail and error.
you move the rollcenter with any adjustment to the j-bar either end.