DerHase
Autocross Champion
- Location
- Hampton Roads, VA
- Car(s)
- 2019 GTI Rabbit
I've run Redshift (BC style) coilovers on a 2200lb Mazda2 and never had issues with clanking noises. With 12k front and rear springs with 0.97:1 M/R front and 0.96 M/R rear. (I ran with no sway bars and had no LSD and this worked best).
Where are your bump stops at ride height? What kind of bump stops? I replaced the stupid hard stock ones with some soft, progressive Ground Control bump stops. Makes a massive difference.
Preload will not do anything with noises. Real motorsport ($10k+ Penskes) do not have preload.
This is probably the best video to visually show the effects of preload. All it does is trade bump travel and droop travel in relation to the shock shaft. With really soft spring rates you do need to have preload, because if not the shock will be almost fully compressed at ride height leaving no bump travel.
I set up "fully threaded" coilovers like in the video... adjust the body height with the spring removed so that the bump stop limits wheel travel right before something interferes, then use the upper collar to set ride height with the spring. Preload be damned. With high rates, chances are the springs will be loose when jacked up. You'll never unseat them while driving because the sway bar will keep the inner spring retained. With lower rates, you may need a bunch of preload to get a reasonable ride height. If it requires a ton of preload (like 5mm+) then your springs are either too soft for your setup, or your shock body just doesn't have enough travel.
I understand this basically flies in the face of what most people say to do... but I challenge anyone to explain why you want a shock body that has unused shaft travel (body extended to get a reasonable not-too-low ride height), or a shock body that is shorter and may risk cutting a tire on the chassis or whatever else may be hitting.
edit: You can see how I set my shock body length on my Mazda2 here... Used a floor jack under the LCA, no springs installed, with a 15x9 and 225/40R15 tire to fit into that tiny car's fenders. I ran actual ride height about 2.5in higher than pictured IIRC.
Where are your bump stops at ride height? What kind of bump stops? I replaced the stupid hard stock ones with some soft, progressive Ground Control bump stops. Makes a massive difference.
Preload will not do anything with noises. Real motorsport ($10k+ Penskes) do not have preload.
This is probably the best video to visually show the effects of preload. All it does is trade bump travel and droop travel in relation to the shock shaft. With really soft spring rates you do need to have preload, because if not the shock will be almost fully compressed at ride height leaving no bump travel.
I set up "fully threaded" coilovers like in the video... adjust the body height with the spring removed so that the bump stop limits wheel travel right before something interferes, then use the upper collar to set ride height with the spring. Preload be damned. With high rates, chances are the springs will be loose when jacked up. You'll never unseat them while driving because the sway bar will keep the inner spring retained. With lower rates, you may need a bunch of preload to get a reasonable ride height. If it requires a ton of preload (like 5mm+) then your springs are either too soft for your setup, or your shock body just doesn't have enough travel.
I understand this basically flies in the face of what most people say to do... but I challenge anyone to explain why you want a shock body that has unused shaft travel (body extended to get a reasonable not-too-low ride height), or a shock body that is shorter and may risk cutting a tire on the chassis or whatever else may be hitting.
edit: You can see how I set my shock body length on my Mazda2 here... Used a floor jack under the LCA, no springs installed, with a 15x9 and 225/40R15 tire to fit into that tiny car's fenders. I ran actual ride height about 2.5in higher than pictured IIRC.