I recently picked up an 88 and have been buying parts to completely refresh the worn suspension(looks like this thing might have the original rubber bushings all around). One thing that I wanted to replace is the springs since it seems that the suspension hasn't been touched in almost 30 years. I've been searching for a bit but i can't seem to find hard answers for what I'm looking for. Does anyone have info on replacement springs for the front of the 88s if i don't want to go with the lowering springs? I'd like to pick up a new set, preferably in a bit higher spring rate, but the lowering sets have appeared to be my only option. Any of you have info on other options that work for the 88 front?
Its very doubtful they are in need of replacement as they carry very little weight. sandblast and repaint them. If you want a slight increase in spring rate and a small decrease in height, cut one coil off with a cutoff wheel.
88 front springs are about 1" shorter than 84-87, so you can get some of those and cut them down to get a mild increase in rate. You can get lowering springs for the 84-87 and see an even higher rate with minimal lowering. Or you can review springs dimensions and moog catalogs to find something cheap to cut down and end up with rates anywhere between 300 lb/in and 600+ lb/in for under $75.
Is there not any risk that they've lost some of their effectiveness after 30 years? I would imagine that the material has fatigued some in that time with exposure to the elements.
On the question of "how stiff?" I'm not certain yet. I'm building the common diy coilovers for the rear and considering doing 300# back there for more of a performance street feel. I intend the fronts to be stiff enough to maintain the feel of a more race oriented ride without giving up too much ride quality. I was going to try a few different values at each end before really making up my mind.
Thanks for the recommendation on the Moog catalog. I see there are tons of different springs listed there. Would you happen to have a reference for the original measurements for the 88 springs?
88 ARD spring specs: Wire Dia: 0.493" Coil Dia: 3.881" (minimum about 3.25") Coil ID: 3.388" (maximum about 4.75-5.0") Free Height: 12.31" Load Height: 7.87" (stock)
I ran some 86 GT springs cut down in the front to get close to a 300 lb/in rate for many years. Then I ran some Moog 7634 (Chrysler Cirrus) trimmed to about 9 1/2" free length (about 360 lb/in rate) for a few more years. A year ago I followed Fierobsessed's lead and used the Moog 639 springs cut down to 8 3/4" free length to get close to 575 lb/in. But all these values are to get a lowered stance vs. stock ride height.
Generally speaking, you want springs that are longer than 12" and thicker wire and smaller coil diameter tend to increase spring rate.
[This message has been edited by fieroguru (edited 12-06-2016).]
88 front springs are about 1" shorter than 84-87, so you can get some of those and cut them down to get a mild increase in rate.
Yep, that's the route I went with my Formula. I wanted to lower and stiffen the ride... so from an '84 parts car, I cut two full coils off the front springs (the set I had happened to be the longest ones that Pontiac had used) and they were perfect. (Lowering springs were used in the back, as IMO cutting the rear springs doesn't work as well due to their shape and the way they sit in their perches.)
[This message has been edited by Patrick (edited 12-07-2016).]
Suspension springs should not generally fatigue or sag with time.
Actually, if the stresses are low enough (as they should be), steel springs can have an "infinite" life; not limited to any number of cycles.
I have had a fatigue failure on a spring (Saturn SL2), but I suspect it got dinged with a sharp tool or something... maybe it was manufactured with a defect.
When I set my 88 up, I looked at everything and then replaced the shocks (with Konis) and the sway bars but left the springs alone, as I assessed them as (correctly, I think) offering little benefit on a street car.
The springs on my 88 had been cut by the PO. waaaay too much. I bought a new set for an 82 Chevy Chevette. They have plenty of extra length to cut to what you need to get the ride height you want. But if your's haven't been cut and you're happy with the way it sits, I wouldn't worry about it.
The springs on my 88 had been cut by the PO. waaaay too much. I bought a new set for an 82 Chevy Chevette. They have plenty of extra length to cut to what you need to get the ride height you want. But if your's haven't been cut and you're happy with the way it sits, I wouldn't worry about it.
When you cut springs you get a higher spring rate, so be careful you don't end up stiffer than you need - calculate what the rates will be at the height you want before chopping.
When you cut springs you get a higher spring rate, so be careful you don't end up stiffer than you need - calculate what the rates will be at the height you want before chopping.
My gray 88 Formula has 86 GT springs on the front, cut by 1.25 coils, and 88 front springs on the rear, cut by one coil. With new shocks and struts, it rides quite nicely, and handles as well as I need it to.
My white 88 coupe has 88 the stock springs in the front, cut by one coil, and 88 front springs in the rear, also cut by one coil. Both cars have poly everywhere except the sway bars and the trailing links (on the coupe.) They sit a little bit lower than stock, in the front, and about stock height, in the rear. Both have fieroguru's rear camber correction kit.
Originally posted by BillS: When you cut springs you get a higher spring rate, so be careful you don't end up stiffer than you need - calculate what the rates will be at the height you want before chopping.
The spring rate on most springs is linear, so if you cut 10% off the length, the rate increase 10% as well. On the stock front springs, the rate would go from 205 to 226 lbs/in which is only a slight increase. Most lowering springs are in the 250-400 range.
The main issue with the 88 front when lowering, is you must trim the front bump stops to avoid riding on them all the time as they are much too tall for most people's desired ride height. The quote below covers most of the needed information to maintain proper suspension travel (and good ride quality) on a lowered 88.
quote
Originally posted by fieroguru:
The cheap way to get a higher spring rate is to get some 84-87 GT front springs and cut 1 3/4 to 2 1/2 coils from them (depending on how low you want it). This will raise the stock rate about 30% and firm up the ride, but not be as firm as most lowering springs.
Just as an FYI for those who didn't take the time to see where the 88 front bump stops hit... this is with the front spring and shock removed with 205/50/16 tires (about 24" in diameter) and the wheel raised with a jack so the bump stop is making contact with the crossmember. This extra gap is additional travel that can be used to help avoid bottoming out on the bump stops - less harsh of a ride (even if you like firm springs).
The bump stops come out with a 13mm socket (single nut holding them in place) and are easy to cut down: Stock with the cut line:
Cut:
New wheel/fender gap when sitting on the bump stops:
If you run KYB front shocks, they are longer than stock and can bottom out internally when the bump stops are cut, so you should add a couple of spacers between the shock and the lower a-arm (some 1/2" nuts work well). Here just the KYB shock is installed and the bump stop removed and I had a very similar wheel gap, so it adding the spacers allows the bump stop to compress w/o bottoming out the shock.
I recently picked up an 88 and have been buying parts to completely refresh the worn suspension(looks like this thing might have the original rubber bushings all around). One thing that I wanted to replace is the springs since it seems that the suspension hasn't been touched in almost 30 years. I've been searching for a bit but i can't seem to find hard answers for what I'm looking for. Does anyone have info on replacement springs for the front of the 88s if i don't want to go with the lowering springs? I'd like to pick up a new set, preferably in a bit higher spring rate, but the lowering sets have appeared to be my only option. Any of you have info on other options that work for the 88 front?
