1988-305-tbi

so i finally got my new weight jacks installed, and i wanted to give a little review. i specified when ordering that i intended to lower the car at least 2" the springs i recieved were 8" #1000 and 9" #200 i can slam the car or raise it to almost stock ride height, the whole install took less than 1.5 hours. i had taken the suspension apart earlier that day when i put on the new ball joints so it came apart pretty easy.

on the front i had to extend the weight jacks to almost 2/3 of the way towards the highest setting to keep the spring seated while i was installing the shocks. as far as the rear goes, with the rear end hanging by the shocks and the weight jacks installed there is atleast 2" of gap between the spring and the chasis, "if rear is allowed to hang down the springs can fall out" so i'm thinking about ways to limit the rear suspension travel, like maybe cutting out the old shock mounts and moving them 2" higher" any one else have any ideas???

the springs sent were made by "suspension spring specialist" or SSS and springs can be ordered throught them or few different places for around $45-60 a piece.


so some of you may think that #1000 lb spring won't be streetable, the ride is great, not much different than wityh the prokit, except the car goes over speedbumps much faster and smoother now, no bottoming out......


and now...for the important part..... words cant describe the improvement, it feels like a new sports car now. the front no longer rolls around like a boat,!!!!!!!!!!!!!!!!!!!! i hear people say, that there car corners like it's on rails, now i know what it means, i cant even believe how great this car feels cornering now, LIKE IT'S ON RAILS

i still need to get it alligned, i can brake the front tires loose a little when i throw it around hard, but if it slides is predictable/ smooth and most importantly controlable.

now i cant wait for the new steering box and wheels to arrive to complete the suspension

Stephen

iTrader: (12)

OK......You post what amounts to lowering discussion & NO PICS!

Where are the pics????

2fast4love

iTrader: (2)

im getting thoose things!!!!!!!!!!!! but do you have align evertime you adjust?

//<86TA>\\

iTrader: (14)

to do it right, yes

Stephen

iTrader: (12)

When my UMI stuff comes in (thanks for the GP Ryan!) I'll put my rear Ground Control Weight Jacks on at the same time.

I'll order the fronts some day, maybe.

1988-305-tbi

i would have taken pics but by the time i did the install i wasn't in the mood.
i got off work friday at 6 pm it was nice out so i decided to install new front lower ball joints. i broke my SS brake lines while putting the a-arms back in, beacuse i'm an idiot and didn't properly support the heavy A$$ strut/spindle/rotor assembly. Long story short i had to get a ride to get new hoses at atutozone. and then blead the system many times, beacuse the autozone rubber hoses suck, and didnt wan't to seal, bad crush washers? after all this nonsesnse it was like 3am and i said "F, IT" i'm going to put this crap on now because i'm not going to want to do it tomorrow.

at first the front was slammed and the rear up a tad. so i adjsusted the fronts, i jacked up the car put it on 2 jack stands, each side , on the UMI SFCs and it took less than 5 minutes a side. to do the rears i supportted the rear of the car on the SFCs and twisted the ajuster sleve up by hand, theres not really enough room to fit the wrech they give you to turn the adjuster, although if you were just trying to get 1/4" i suppose the wrech could be used


p.s. i didn't realize how much the SS brake lines helped until the rubber crap came back, they will get replaced with the SS lines again, when i do a brake upgrade next month, i hope, if i have money.

2fast4love

iTrader: (2)

in that case i will slam and thats all, tires are expensive so i will keep it that way. im going to put it on my iroc i wanted to do my z28 but im going to use drop spindles of my pinto rack so i only have to buy one set thankfully. im also hoping to have some money at the end of the month haha!!

paul_huryk

I wondered about those, but don't have them. Do have the adjustable rear spring (with height collars) from FC and I like them...

When you get some weight off the front end, it will make another huge improvement. Hood, aluminum heads, baer brakes, a/c delete...

Stephen

iTrader: (12)

I wasn't looking for install pics, but pics of how the car sits after the install. Got any?

Duratys

Can someone post some pics of these with the wheels off?

Are these for a weekend cruiser or a dedicated track car?

gunner53227

Did you replace your shocks and struts when you installed the springs?

1988-305-tbi

theres spmoe installed photos in this post>>>
https://www.thirdgen.org/forums/susp...o-project.html


i installed the koni's last month, this car is my daily driver....

i'm waiting for my new c6 wheel to arrive, maybe i slam it and take some pics after i get thoose on

I H8 WWD

iTrader: (5)

Someone tell me the size of these GC WJ's fully lowered and fully extended (k-member mount side to spring side of plate). I need to find out what size springs I will need with this all the way lowered. Thanks.

1988-305-tbi

it's about 3", to lower 1-3" you need 8.5"/9" springs

I H8 WWD

iTrader: (5)

Umm.

(In relation to first two pictures)
Front= 3" completely screwed down (Lowest point)
Front= x" completely screwed out (Highest point)

(In relation to last two pictures (Next Post Down))
Rear= x" completely screwed down (Lowest point)
Rear= x" completely screwed out (Highest point)

This is what I need for both front and rear type ground control weight jacks as the front is a plate style and the rear is a threaded ring.

I H8 WWD

iTrader: (5)

Last 2

//<86TA>\\

iTrader: (14)

shame you didnt ask a couple weeks ago, i just installed a set and could have gotten measurements.

1988-305-tbi

for the front the closed height is about 2.25" and the banjo bolt is 5" long so maybe 6.5" extended i saw that you plan on running drop spindles, so you need a 9.5"-10.5" front spring and youll be set and the shortest rear spring possible, i have my rear set all the way down, and wish i could go 1/4" lower but 9" is the shortest pigtail spring i could find.

the rear adjuster raises the rear spring about 1/2" above the original spring pearch and has 3" of adjustment

I H8 WWD

iTrader: (5)

Here is what I figure now with the new information (roughly). I want 2" of drop all around. Using Koni yellows. Stiff to real stiff ride (to keep from bottoming out and such).

This will show what I have and what I will need now.

Front:
-Moog 5662. Install height of 10.75"
-Ground to fender lip is 27.75"
-Add front Weight Jacks. New height is 30"
-Add 2" Drop Spindles. New height is 28"
-New spring must be 2.25" shorter (To achieve my 2" drop). New spring is 8.5" otherwise an 8" spring. (Weight Jacks will compensate for the .5")
-Since I have lowered the car 2", I figure add about 10-15% more spring rate for every inch the car is lowered. So around 25% more spring rate is what I figured would be good to keep the car as stiff as I need to keep from bottoming out easily.
-25% more spring rate from the Moog 5662 spring rate (748#) would be around a 937.5# rate or 950# even. Leaving me room for higher and stiffer rates.

Rear:
-Moog 5665. Install height of 10"
-Ground to fender lip is 27.75"
-Add rear Weight Jacks. New height is 28.25"
-New spring must be 2.5" shorter (To achieve my 2" drop). New spring is 7.5" otherwise a 7" spring. (Weight Jacks will compensate for the .5")
-Since I have lowered the car 2", I figure add about 10-15% more spring rate for every inch the car is lowered. So around 25% more spring rate is what I figured would be good to keep the car as stiff as I need to keep from bottoming out easily.
-25% more spring rate from the Moog 5665 spring rate (107#) would be around a 133.75# rate or 150# even. Leaving me room for higher and stiffer rates.

Sound good.

1988-305-tbi

sounds like you're on the right track as far as height and spring rate, with my 2.5" drop and #1,000 8.5" front springs i am about 2/3 of the way adjusted towards fully exteneded. if i had drop spindles it would cause me to adjust the front weight jacks to fully extented...... and i would need a taller spring you might want to think closer to 9.5"

I H8 WWD

iTrader: (5)

Yes the sizes I have are install heights and not free length, But I am sure if I buy an 8" spring it will install lower than 8" due to the load. So I think going 1" larger on each spring will be perfect. 9" front and 8" rear. If anything springs are cheap and can be swapped fairly easy. Thanks.

X77trinity77x

I have an 89 trans am and my car exhaust keeps bottoming out
I know i have the whole ground control kit from groundcontrolstore.com
I bought the car with it already installed
I'm not sure how to adjust the springs or shocks I'm new to working on cars and with it being aftermarket performance it's a hard thing to learn on

I dont know how to adjust the struts
The shocks or springs
Can anyone on this thread help or point me in the right direction maybe a video? Thanks

QwkTrip

iTrader: (22)

The front weight jacks have a big screw in the center that adjusts height. A 3/4" ratchet will fit in the end and you can turn the screw to raise/lower the car. There is a grease zerk fitting at the top (out of reach, of course) that will lubricate the threads.

The rear has an aluminum collar that the bottom of the spring sits on. You have to completely unload the rear suspension (let axle hang free in the air) and then turn the collar to raise/lower the rear. There is a set screw that you might have to loosen before turning the collar. You'll be able to turn it by hand if the springs are not pressing against the upper spring pocket. You'll need a special little tool to turn it if the springs are compressed any. You can contact Ground Control Racing for the tool.

McLovin1181

I hope y'all are modifying your roll centers to correct suspension geometry after lowering.

QwkTrip

iTrader: (22)

Oh, come on. It's not like the car blows up if they don't.

I hope they're having fun with their cars. 99% of people don't care and don't need to care about that stuff. They're just driving, and frankly will never drive in a way to discern the difference. The other 1% can enjoy kicking their butt in the handling department by paying attention to the details.