STA

iTrader: (1)

If your happy with the pro kit and HDs why would you do another spring? Something Stiffer? Just curious, thinking about using your setup and looking for input.

Sam Strano

iTrader: (41)

Springs and shocks have to work together. That's the case for ANY spring. He has stock shocks with lowering springs, it's not going to work well, period.

It's not you are hitting the stops ALL lowering springs do, hell so do the stock springs. It's that you aren't getting any help from the shock in two ways. Any meaningful compression damping on the way down which makes you slam into the stop harder, and a complete lack of rebound control on the way back off the stops.

There are plenty of folks with Pro-kits that are very happy, but you'll find those folks also have good shocks too.

WS6freak

iTrader: (3)

I second that.

Eibach Pro Kit + Koni Yellows Single Adjustables + 315s = no rubbing

jimmyblue

iTrader: (11)

I have Hotchkiss and about 1/4-1/2" rise off my air shocks
and have only bottomed out the rear on a couple of
occasions; messed up roads. But I also do have to grandma
it over any foreseen bumps to avoid tagging the Y-pipe or
trans pan. The Hotchkiss do have a higher final rate than
stockers but are playing catch-up with the first inch of
drop and sometimes you just don't win. I found the HD
(=SLP) Bilstein rears unpleasantly harsh and the rear
height did not look right, hence the Gabriels. You could
try that and, if you don't like it, it's a $80 experiment
down the tubes.

Fulton 1

iTrader: (9)

With Prokit springs and SLP Bilsteins (rears are same as HD Bilsteins) I never even realized how badly I was bottoming until I installed my 12-bolt. Because of a condition with my wheel speed sensor I spent some time montoring rear axle travel and noticed I was bottoming regularly during street driving. For a temporary fix I swapped the rear Prokits for Hypercoils and I'm happy with the results. Is it the ideal solution? Doubtful, but it works for me until I get my LG coilovers next spring

JasonWW

iTrader: (2)

If you want to try a cheap experiment, I would recommend simply adding 2 rubber or steel spacers to each spring. Just jack up the car by the frame to uncompress the coils and slide them in. The metal ones tend to have twice the effect of the rubber ones. Adding them to the closer coils will increase ride height without hardly any effect on spring rate. Adding them to the wider coils will increase spring rate and reduce the amount of contact with the bumpstops. So try some out and see if that fixes your problem.
http://gmocart2.gmotion.com/store/me...ing_suspension
http://gmocart2.gmotion.com/store/me...ing_suspension

These units are great for a performance application. Try it before you go off and spend big money on parts you may not need.

Jason

redsscamaroboy

iTrader: (7)

I have the Eibach Pro kit and had to add urethane coil insulators to the rear springs just to make it level(did sage in rear). I also removed the metal portion of the bump stop and that helped a ton also.
I DO NOT recommend removing the entire bump stop,that was not pretty when i hit a set of bad R/R tracks.
I want to return to the stock springs but i can not find mine???????


Anyone want to trade a GOOD set of stock springs for a set of Eibach's?
Dave

2FAST4U

It is fine to remove the bump stop! the suspenion would work at all if you are on the bump stop! The fact is that not having the bump stop wouldn't hurt the car or suspenion at all! I have never hit the bump stop with the stock V8 rear springs and koni SA!

nvrstsfd23

I took out the metal spacers and it fixed the issue alot it still bottoms on hard roads and tracks. I need shocks what would u guys recommend. With xmas coming I think I am going to ask for shocks, subframe connectors. What else should I get.

Sam Strano

iTrader: (41)

I disagree it's fine to remove it. But I also don't buy that quote. I've NEVER seen an f-body that hasn't touched the stops with ANY rear spring people. And they certainly do with the stock springs. All you have to do is look at the axle under the stop, you'll find it's shiny from the bumpstop rubbing it. With proper damping it's not an issue. Note that most of the folks who complain about "bottoming out" have shocks that don't work particulary well with Eibach's or toss a ton of weight in the car with no regard to the spring rate. Again, I want to re-iterate that if the definition of "bottoming out" is hitting the bumpstops, ALL springs bottom out.

John_D.

iTrader: (2)

When I was running the pro-kit springs all around on my car, and had the rear isolators off, there was only enough room to slide a key (flat) between the bumpstop and the axle tube, and that's it... (my car didn't have any spacers in the bumpstop)

When I put the isolators back in, I could get a finger in there (between 5/8" and 3/4"), but it still jarred you when going over small bumps.

I recently put the stock springs back on the rear. Left the bigger rear bar on there, and left the stiffer shocks on it. It rides much better now on the road (has some compliance), and still corners well with the sway bar and shocks doing a large portion of the work.

I still have the eibach's and the koni's on the front.

PeeDee

If you have the Eibach springs and wheels with more than a +20mm offset you are doing more damage to your car than you probably realize. Under car problems will be obvious- dented exhaust is the most common. Where you won't readily see problems is the top of the rear fender- right where the corner of the hatch meets the fender. If the tires have contacted the fenderlip, more than a couple of times, you will see waves or buckles in the sheet metal- about $250.00 for a paintless dent repairman to work them out.
Some guys roll the fenderlip- unacceptable to me.
Expensive coil over shocks- waste of money- *** busting ride- got a set on the shelf if anyone is interested.
Airbags- helped a little, too noisy and will bind the springs- got a set for sale.
Ride height adjusters- big pain in the butt to adjust and very easy to damage threads- threw them in the junk barrel after breaking two spanner wrenches.
Custom tuned shocks- got three sets- look nice hanging on my garage wall- they are for sale too.
Removing or shortening bump stops- just adding to the problem.
Air shocks- started with Gabriels, set at 35psi for regular driving- picks the car up 3/8" in the rear, car is level, no "Ricer Bounce", handles well and does not bottom out or have tire contact with fender. Set them to 40 psi when loaded- two adult guys, luggage, a cooler of iced down beer and tools- it will not bottom and I don't have to tippy-toe around bumps. These are hydraulic shocks with air assist.
Custom built gas shocks with air assist ( tuned for lowered F-body)- Just installed them this weekend- running 20 psi- does not bottom out or contact fender, hooks up like crazy, corners extremely well, sits level and rides smooth but firm.
HMMMMMMMMM- maybe this old hot rodder has found something to solve the continuing problem of bottoming out and scraping tires!
Contrary to some opinions- Air shocks aren't just for towing. $140.00 sure beats the hell out of the other exensive options and you can drive/ enjoy your car.
If you are around Atlanta, Ga. and want a demostration, get in touch. I'll take you over to Cheaha Mtn. Ridge near Talladega (12 miles of serious road)- I'll buy the fuel and show you what this setup can do- without bottoming out or banging the fenders. After I release your butt suction from the seat-If you aren't happy with the results- I'll buy dinner/lunch and the beer.

JasonWW

iTrader: (2)

PeeDee, I'm sorry you had so much trouble with your setup. Did you try and get some help to figure out the problem here or in another forum?

Generally speaking, the rear factory bumpstops are just too stiff and come into play too soon. I have some custom bumpstops and 170lb springs along with 315's, Koni SA's and a 26 1/4" rear ride height and have no problems with rubbing, bottoming out etc... I have plenty of suspension travel and the ride is quite smooth. The bumpstops are being used, but are so progressive, I can't feel them. Here's a quick photo of how I mounted my bumpstops.

I know Sam doesn't like this method but it works extremely well so far.

JasonWW

iTrader: (2)

Here's a pic when I first put the new shocks on. This is with the factory springs and ride height.

PeeDee

JasonWW,
Cool, looks like another good approach to the problem- worth looking into. Have a couple of questions:
Are you running the stock 10 bolt rearend or a 12 bolt?
Do you have a stock wheels or after - market with more offset?
Seems as if all these things come into play regarding bottoming out and tire scrub.
I have a fairly new set of BFG Drag radials- one with a six inch slice in the side wall, from fender contact.
I guess we all eventually find what works best for each us.
An added benefit of my set-up is that I am able to dial in the rearend for the drags- even lowered, I have no wheel hop, hook up is excellent and I am running 12 flat on my street tires.
As a note - I have a 70 Hemi Road Runner ( #4 of 12 built), factory lite- weight Super Stocker. It was delivered with soft rear springs for weight transfer and heavy duty air assisted shocks to keep the tires planted. They must have known something way back then. I am the original and only owner of this car, so I know it has never been modified.

JasonWW

iTrader: (2)

It's the stock 10 bolt rear.
I have 11x17 ARE Torque Thrust II's. I don't know the exact offset, but they make a size just for these cars.
I've also rolled my fenderlips to about a 45* angle, beat in any areas on the inside where it was rubbing and installed an adjustable PHR to center the axle just right.

This is all common when fitting 315/35/17's to a lowered car though. It's not as bad as it sounds and is well worth it.

I don't really drag race so I didn't set it up for max weight transfer. I also don't carry any big loads in the rear. If I did, I'd probably raise the ride height a little.

PeeDee

I see, you have had to do some work to fit those fat tires in the wheel well. My car is not a drag car- It's set up more for highway and twisty roads. Enjoy going to car shows, races, etc.- normally with a passenger & assorted luggage. I looked into 11 x 17 wheels when I put on the AR 220S set up- saw all those clearance issues so I stayed with the 9.5's.
With the air out of the shocks, my ride height is 26.5" (passenger side), 25 7/8" (driver side)- springs have sagged unevenly. With 20 psi in the shocks the car sits even at 26 3/4" will not bottom or rub. For loaded driving(gear & passenger) I set them to 35 psi,
27" ride height, settles in at 26 5/8" loaded with no problems.
Haven't been happy with the Eibach springs- looking at Hotchkis or Hypercoils.
Did you get the shock bump stops from Koni- did they come with the shocks. Have a set of Koni's hanging on the garage wall.

JasonWW

iTrader: (2)

I bought the 55mm ones seperately. The Koni front shocks should have come with the 40mm ones. I have some more detailed info here.
http://www.ls1.com/forums/showthread.php?t=507015
http://www.ls1.com/forums/showthread.php?t=505485

PeeDee

Great- Thanks for the links. I will check it out. Could be a positive addition once I get these sorry Eibachs off the car.
This what I like about hot rodding- a million ideas and good people always looking for a better way to do things.
Drive Hard & Stay Safe.
Pee Dee

mario65

iTrader: (7)

Not all rear springs bottom out. I guarantee there is a great difference in the eibachs and g2 springs. Ther ride is better with the g2's because they never hit. The g2 car I have out handles the prokit car hands down.