I am currently looking for new suspension for my 96 civic hatch. I was originally planning on getting some blox full coilovers because I really liked my friends car that had the omnipower 12k 10k coilovers. I understand that this is very stiff for a street car but I have daily driven 8k and 6k rates with kyb adjustables for 4 years and I think the ride is pretty soft. What I was worried about was that if the blox coilovers blow I am pretty much screwed where as koni and progress I can get replacements. I would like to run at least 500 pound springs front and rear and maybe even stiffer than that later on. I like the progress shock because I really do not care to have an adjustable shock as long as it can handle my spring rates. I have adjusted the kyb's and have never felt any difference so I left them at full stiffness. So basically will the progress shocks handle these spring rates as well as the koni yellows? In the progress sales thread the seller said that their shock is comparable to the koni yellow's green line on their shock dyno plot if that helps at all?

Also, I am guessing that these taiwan made coilovers(omni,blox,d2,etc.) shocks are not actually stong enough to handle the rates they come with so how are they getting away with 12k and even 18k rears without blowing the shocks?

 

Yellows will cap out at 500lbs, not sure about Progress.

I know this much, if your going stiffer then 500lbs in the future Yellows are not the way for you w/out risking shock blowout.

 

I ran 550 rear rates on my car for a little over a year with racing every weekend and street driving every day. The shocks held up just fine. I've heard numerous times over from others and from Red Shift Motorsports(where I bought my Koni/GC's) that the Koni Yellow Sports can be used with up to, but not past, 600lbs/in springs.

I do not know of the limit for Progress's shocks. However based on their websites information and especially their warranty information, I think it's safe to assume that their shocks really aren't meant to be used with rates as high as 500lbs/in. If you go above their "Street Performance" kit, which is 350F/250R, they will not warranty the shocks. They do sell their "autox/drag" setup with 500lbs/in rear springs, but wont warranty it and I can only assume that they may expect you to expect replacing the rear shocks in a fairly short amount of time... The shocks are non-adjustable and the rates they offer for Street Sport and Street Performance are probably the best to stick to with these shocks.

For what it's worth, I'd say go with the Koni Yellows. They will definitely handle the 500lb/in springs you're looking for. BUT, remember that they should not be used with springs higher than 600lbs/in. If you want to go higher than that, you'll have to have them re-valved. Which is also one of the nice benefits of using the Koni's.. I had mine re-built over 2 years ago for 650 front and 850 rear springs and they're still great. Although stupid rough on the streets lol.

To answer your last question about blox, d2, etc.. using high rates, they aren't getting away with it. Just because they offer it and might sell it doesn't mean it works or works well lol. Stay away from them. Go with Koni.

 

Thanks for taking the time to really answer my question in detail. I didn't know that progress didn't warranty the stiffer rates so I am glad you mentioned it. I think I may have to spend some extra money to get the konis and ground control to get the setup that I want.

BTW, do you have the off the shelf konis that you had revalved or do you have the spss3 version that have a shorter length. I am thinking that I may need to do extended top hats with the off the shelf konis.

 

Konis won't blow at 500lbs+ the shocks just start to be under-damped at those rates. Getting the re-valved is suggested. Or buy the koni race shocks.

That said, I love my progress CS-II, I've put 5 track events and about 6,000 miles on them and they still ride great. People that have ridden in my car at track events think the car is well setup, not too stiff, and might just need stickier tires.

 

I inquired with Progress on their dampers before purchasing my CS-IIs, and I was informed their warranty, and therefore reccomended maximum spring rate, is good up to 500lb springs, which they include in their AutoX/Drag kits.

 

I had originally bought ots Koni's but have extended top hats and the shock body a little low in the damper fork for extra travel. You really only need the extended top hats for the front, the rear has quite a bit of travel room. Unless you're really slammed..

Hmm, guess I missed the change. I was pretty sure I had seen on their website that they did not warranty the higher rates but after looking at it again, seems like they offer a 1 year limited warranty for all the setups.