RaverRacerX

specifically:
20700-6

and

25150

anyone have experience with these springs?

wdigitog

I'm curious too.....Afcos come in much stiffer versions than Moogs but I was wondering about which length to get.

RaverRacerX

anyone?

Roostmeyer

iTrader: (3)

Maybe instead of posting part numbers you should post the specs?

Also, is a factory weight car? Even then there's enough options and variance to make it difficult.

wdigitog

Well, the stock front springs measure 5.5X15.5" ....the Afcos are 5.5X11"...4.5" shorter! Now the spring rate is higher....600 vs 900 or 1000...does this mean the ride height will still be good, too low or impossible?

RaverRacerX

700lb and 150lb spring.


and roost, i asked because the rate is about the same that people have said the moog 64's were. the height will really depend on what the installed height is.. hence.. the thread.

hellz_wings

iTrader: (2)

If they are that short, maybe they would be best suited to be run with weight jacks?

RaverRacerX

from Afco's website:

"Stress Consideration in Spring Design
Many times, because of the long stroke requirements for certain rates of racing springs, material strength must be sacrificed to achieve significant stroke. Couple this with the fact that the ideal wire diameter is not always made and you can see why some springs have a real potential to take a set. We have seen some brands of springs lose as much as 15/16" of free height during normal operation. To eliminate any set from occurring at the race track, it is good manufacturing policy to pre-set (press to solid height) all racing springs during their manufacture.

If done correctly, pre-setting will generally eliminate any potential for additional set, even when springs are designed with smaller than ideal wire. Shot-peening will further enhance a spring's durability. It should be pointed out that all Afcoils are pre-set and shot-peened during manufacture."

so with that in mind and the 10.75" install height of the 5664 moog spring... theres a conclusion there that im not experienced enough to be privy to..

Roostmeyer

iTrader: (3)

Those springs will be too short for that spring rate. The 10.75” loaded is height is the height of the spring compressed in the car sitting still. If those are 11” long free height they’re going to be 1.5-2” too short at the spring. At the wheel you would be hard on the bumpstops. The 707lb/in iroc springs are 13.18” long if that gives you an idea.

I would suggest cutting stock or stock replacement springs or if you want to go significantly stiffer you could use something around a 5.5x12” long 850-900lb spring.

RaverRacerX

i have this issue where i try to find things that work that not many use

if they dont work, they dont work. ill go with what does. i dont want to go to such a high rate that i cant do what i want to with my car.

monkey-leader

Digging up a grave here, but did you guys ever find out what worked for you?

I know the Moog 5662's free height is 13.01" with a free height of 10.75. The rate is 748 lbs/in and installed its loaded at 1690 lbs/in. So they would be pretty stiff.

The Afcos (PN 21000-6) come in 1,000 lbs./in. Rate, 11 in. Length, 5.50 in. Diameter. Listed as fitting for our cars. The rates go up to something like 1300 lbs/in if you want. I imagine the 1000lb/in. will drop about 1.5" to 2" and sit at about 9-9.5 installed.

I'm thinking of using weigh jacks in my set-up, so I'm unsure if ill have enough room to play with. Cutting up some Moogs is one thing, but Afcos is another story. The rate will go through the roof.

They have another listing of 21000-1 which are 9.5 inches in length. but these might limit my travel too much for anything but oval tracks?

monkey-leader

bump, for science...

cosmick

If you're wanting the stiffest Moogs, the 5664s are stiffer than the 5662s because the 4s have the larger wire size. The published rates are in error.
Ultra-hard springs are no practical benefit, the real goal is a higher wheel rate, and the best way to get that is with coil-overs. Especially if you can either go 20 MM narrower on the front tires, or move them out 1/2".

monkey-leader

Not going to be possible. Likely going to have 305/35/18 up front.

So the catalog is wrong for the 5662s?

cosmick

better to have a well-controlled 285 on a 10.5 than a poorly-controlled 305 on an 11. And by better I mean more predictable, more ultimate grip, and more cornering power. Besides, there are 315/30R18s, which is actually a bit too much for common 10.5s, 11s would have to be custom at roughly 4-5 times the cost, and I can't find the oddball tire size you propose. just try it right to begin with, rather than redoing it right later at more total cost.

monkey-leader

Quote:

Originally Posted by cosmick

better to have a well-controlled 285 on a 10.5 than a poorly-controlled 305 on an 11. And by better I mean more predictable, more ultimate grip, and more cornering power. Besides, there are 315/30R18s, which is actually a bit too much for common 10.5s, 11s would have to be custom at roughly 4-5 times the cost, and I can't find the oddball tire size you propose. just try it right to begin with, rather than redoing it right later at more total cost.

Thanks for you input. The tires really aren't that odd of a tire. Google found it instantly. Probably with some spacers and corvette mags.

Example:
http://www.summitracing.com/int/part...1180/overview/

As far as your coil over suggestion, I fail to see how that is even remotely less costly. The whole shebang runs for over 1000$?!?!

I went with some weight jacks and the Afco 5.5x9.5" springs at 1000lbs. should be a 3.5-4 inch drop compared with the Moog 5662s.

I'll be raising the front with the weight jacks to compensate.

I'll let you know how it rides in the summer.