B13Birk
HalfDork
11/21/22 9:05 a.m.
As some of you know I am currently piecing together a 280zx challenge car. I have found that S13 (240sx) coil overs can be easily adapted to work on my Z. The Build So Far
My question is... How bad is good enough? I have ZERO experience with Chinese coil overs like Maxspeed and rev9 or even ones with ZERO brand name on the internet. I have found a set of off-brand coilovers for $100 and I'm just curious what the Challenge Hive mind thinks about running this type of setup. Not saying these exact ones, even new Chinese ones are $200 on ebay. I know they are junk... But are they usable junk? What if the springs are swapped out to something more pro? Anyways... tell me what yall think?
The other option I know is to run normal struts with Coilover sleeves. Does that tend to be a better option than a true coilover?
Unknown condition coilovers = three are blown, not sure about the fourth one and I can't tell the difference anyway?
My guess is that you'll be better off with stock shocks and sleeves, as long as the stock shocks are in decent shape. At least if you can't rebuild the coilovers yourself.
I ran Chinese sleeves and springs on my stock Miata Bilsteins a few years ago. The whole thing cost $40. The shocks were in good condition when I bought the car. Ended up tied for second at the Challenge autocross. I wasn't able to find cheap coil overs that didn't have at least one shock leaking.
The ones I tested had fundamental geometry problems that prevented them from being usable. Had the geometry worked, adding more pro springs would have just meant they were poorly damped - they managed to be both over and underdamped at the same time.
The springs are probably the most reliable part, as long as the metallurgy isn't total trash they'll easily last the Challenge.
Just drop it on to the bumpstops and pretend it's a kart. It's not like the Challenge involves any real roads :)
Stampie
MegaDork
11/21/22 12:51 p.m.
In reply to Keith Tanner :
There's actually a significant dip in the north west corner of the autocross area. I'll have to look later but I'll try and find Pete's comments about it in my underdamped Q45.
I built a set of coil overs using a set of cheap eBay (found on CL for even less $$) and a set of closeout Gabriel private label struts off Rockauto (less than $3.00 each). Look hard before you buy potentially blown-up stuff.
B13Birk
HalfDork
11/21/22 7:47 p.m.
All of your feedback has been very helpful. Thank you. Anyone else feel free to chime in.
Any suspension design works if you don't let it move. (Or something to that effect)
I dislike roll in an autocross car and want all the spring rate I can get. YMMV
No-name-at-all coilovers are very questionable even by Challenge standards, but the good news is that if you're willing to gamble on them and put in the effort, you can try them out and if they're too awful, then you can switch to something else and there's no budget hit. Also keep in mind that at least 1 car has done well just running on the bump stops...
Just use washers as springs... ask the guys with the echo. Super stiff for autocross works except on the bump, a stock setup would probably work best for the drags.
Toot
New Reader
11/25/22 3:23 p.m.
I know a lot of people don't like max speeding coil overs but we have run them on 2 Miata's and a 350z and they worked really good for what they are. I feel they would be better that great shocks and springs. I'm basing this off my experience which I mostly have run feal and Olin's coil overs on Miata's and Porsche. They will not last on a big track but for autox they will be fine
In reply to Toot :
How did you get around the lack of rear bump travel on the Miata? Were you using them in a lifted application with oversized tires?
Toot
New Reader
11/26/22 5:22 p.m.
In reply to Keith Tanner
it's funny you ask. I actually just took them out of the box and put them on on adjusted them down about 1". Never had a problem with bottoming out on the miata at all. The 350z had separate rear springs/ shocks. I sold 2 Miata's with those on it. 1 for a drifter and 1 that has already done 2 8hr races. Let me be clear they are not Olin's or feal but they worked better than the bilsteins at Sebring.
Then the geometry of yours was different than the geometry of the set I was sent. "Drop it down an inch" wasn't actually physically possible. If you had tried to race with my set at Sebring you would have pounded your spine shorter while getting passed by stock Miatas with blown stock shocks.
The damping was also obviously crap, but the constant slamming from the back overwhelmed that.
Toot
New Reader
11/26/22 11:23 p.m.
In reply to Keith Tanner :
I found the spring rate was to soft on the ones I tried. Actually driving this miata (first time ever in a miata) made me park my m4 and build my own. I drove that car for an hour straight at Sebring. I don't want anybody to take this like they are good coil overs but I can tell you they are good enough for the $2000 challenge.
We'll have to agree to disagree on that one. In my experience, they would have been a waste of good budget on a Challenge build.