Unloading the rear tires

The baseline buckets will only work with their upper arms or a custom set. They are shorter than regular uppers.
 
The baseline buckets have to be used with their arms or a custom set. They move the mounting point closer to the rearend so regular arms would be too long.
 
Imo, people try to do too much all at.once, amd never get thing set right. The next problem is thinking you have to launch off a transbrake to get the best 60'. Without proper parts and settings, a radial car will never work right off the brake. I have been 1.34 in a high 9 sec car with stock arms, sway bar, and shocks with a 275/60 radial pro. Only mod was 1 air bag with 28psi in it. The car left with the left front 2 feet in the air and the passenger on the ground, but it worked. You dont need fancy shocks until low 9s IMO. Most cheap out (like I did) and buy either comp 3 way, or 90/10 front, which are way too loose for a low 10 sec and faster car. Or they have big dollar double adjustable shocks that are set wrong, and the car porpoises. A bias ply tire will band aid this some, but a radial will go up in smoke.
 
I found this winter that most of my problems were weight distribution. And some of it was corrected with just adjusting the coilovers and anti roll bar. I was 56% on the nose, so I installed a rack and moved the battery to the trunk to try to get to 53% on the nose.
I've got to re-weigh it in a few weeks.
 
I have some work to do if I want to run TSM and get my 60's into the 1.2s. What killed my car was when I added the 12 bolt and 3.73s. I also switch to a 20 blade from an 18 blade, but I think the gear did more. I also had 3 year old radials, so that doesnt help. I am switching to 29.5x10.5 mt pro bracket slicks to kill the gear to keep the rpms in check with the 3 bolt.
 
The car picked up 2mph, it wanted to run to 7000rpm. I dont think the 3 bolt will be happy there though.
 
Why did you go to a 12 bolt? Just curious. I don't think it offers much more durability than an 8.5 ten bolt but comes with the hassle of needing axle retention and different arms to install it. Just seems like to me, a nine inch has the axle retention, ease of gear swap with an additional chunk and bolts in with the arms already there.

Us cheap guys go with a stiff spring, and less stiff shock in the back. And a stiff rebound on the cheap shock on the front. Might look at tire pressures also. Not everyone can swing coil overs and three way adjustable shocks to dial it in and some $330 brackets and upper arms are way out of the budget( though you will see em one my car one of these days as they WORK).
 
Why did you go to a 12 bolt? Just curious. I don't think it offers much more durability than an 8.5 ten bolt but comes with the hassle of needing axle retention and different arms to install it. Just seems like to me, a nine inch has the axle retention, ease of gear swap with an additional chunk and bolts in with the arms already there.

Us cheap guys go with a stiff spring, and less stiff shock in the back. And a stiff rebound on the cheap shock on the front. Might look at tire pressures also. Not everyone can swing coil overs and three way adjustable shocks to dial it in and some $330 brackets and upper arms are way out of the budget( though you will see em one my car one of these days as they WORK).
Its a moser 12 bolt. The 12 bolt ring gear is stronger than a 10 bolt.
 
Can someone explain what Instant Center is?

How you can tell it is off?

And how it is adjusted?

thanks
D
 
You know what center of gravity is D? Instant center is a point where weight is transferred, kinda like a pivot on a lever. Most of the weight in a G body is in the front, and the rear arms, being triangulated, (configuration) have an imaginary meeting point. That point is the fulcrum, the axle is one end of the lever, and the body is what you're trying to move.When you hit the gas the tires cause the axle to rotate and with the arms in the right location, can transfer weight to the tires getting decent traction. The factory position for this is in front of the bumper. With a relocation of the upper or lower arms you can change that transfer point to get better traction.
 
Go to the baseline suspension website and he has a calculator you can out your measurements into to get IC
 
baseline.jpg
you also will need longer lowers as the tire will end up to close to the WWell,so buy the whole kit .I think Sack may still have some for sale

http://www.baselinesuspensions.com/instant-center.php

my car before and after old set up was SS lowers and adj uppers
 
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Once you fit the baseline kit and correct the IC you will be shocked by the results, I went from up in smoke at various places down the track to stuck like superglue and worrying about my seat mounts...
 
Correcting the IC will let the car dig harder, but what most don't get is how the rest of the suspension can effect the launch. 90/10 shocks can help as well as hurt but you need to look at everything, not just the rear arms and their location.

I've said this before and most blow me off, but if you stand at the drivers side and think about this it will make sense. The drivers side tire will be turning counterclockwise and the axle will be trying to turn clockwise. The pic I want to post won't load so look at the disc brake conversion I posted in the how to section. The spring perches are welded off towards the back of the axle tube, which actually helps the axle rotate clockwise. By just cutting the mounts off and flipping them so they overhang the front, the axle will not be able to rotate as easily. This creates more lift to the chassis..The spring mount is nothing more than a pressure point that acts like a lever and if you put more pressure on the front of the axle then you will plant the tires even harder.;)
 
Sub'd

Anyone know the estimated weight of the rear, for the GN? Only change is a missing spare tire and jack.
 
Correcting the IC will let the car dig harder, but what most don't get is how the rest of the suspension can effect the launch. 90/10 shocks can help as well as hurt but you need to look at everything, not just the rear arms and their location.

I've said this before and most blow me off, but if you stand at the drivers side and think about this it will make sense. The drivers side tire will be turning counterclockwise and the axle will be trying to turn clockwise. The pic I want to post won't load so look at the disc brake conversion I posted in the how to section. The spring perches are welded off towards the back of the axle tube, which actually helps the axle rotate clockwise. By just cutting the mounts off and flipping them so they overhang the front, the axle will not be able to rotate as easily. This creates more lift to the chassis..The spring mount is nothing more than a pressure point that acts like a lever and if you put more pressure on the front of the axle then you will plant the tires even harder.;)
So is there a kit needed to move the spring purch to in front of the axle?
 
So is there a kit needed to move the spring perch to in front of the axle?
There ate several kits that you can buy from dirt track suppliers, but you don't need one. All you've got to do is cut the mounts off and flip them 180 degrees. Weld them back and it will hang over the front enough to help offset the chassis. Use a cut off toll or even a hacksaw but leave the factory welds as a guide.;)
 
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