DRM coilovers & spring rates
 

Many of you guys have this coilover kit on your cars and from what I understand various spring rates are used according to preference.

My question is what your experiences are regarding spring rates, what do you recommend and why so.

Doing all the bushings and shocks etc anyways and think I want to ship over this kit too in the container. Our car is a 94 ZR-1.

Brackets from Carter is also on the list but is there anything else to think about (besides the lathe job on the rings) if installing this kit?

Thanks and Merry Christmas to all of you [emoji318][emoji319][emoji1762]

**I can add I have emailed Randy (DRM) too but appreciate personal experiences shared here also**

https://www.dougrippie.com/c4-corvette-coilover-kit

Sent from my SM-G955F using ZR-1 Net Registry mobile app

Re: DRM coilovers & spring rates
 

I have 425 and 325 pound springs on my car. That's what was on the car when I received it. With the FX3 set on tour I don't like how the car feels, vague and floaty. In Sport the ride and response is tightened up and it's fine for driving on my local roads which are a combination of good roads and crappy potholed surfaces. I've not done hard nearing the limit) cornering so can't comment on that.

I've barely run it in the performance setting so can't comment on that.

I have poly bushings all round as well.

My car is moderately lowered as well. I'm happy with the setup I have and am not inclined to mess with it.

Re: DRM coilovers & spring rates
 

I can't fully comment since my car was equipped already when I purchased it. So I don't have any experience with the stock setup for direct comparison for example. I'm also not exactly sure what spring compounds I have, can't find any visible markings, but they are a kind of metallic dark blue color in case color coding means anything. Doug Rippie's website doesn't seem to have options for spring rates.

What I will say is keep the FX3 adjustable shocks with the coilovers. My car in tour mode is quite compliant and soft ride (with considerable sacrifice in handling - can feel the roll and sub-optimal levels of mechanical grip). If not doing any spirited driving and just a true Sunday cruise with the wife, she is happiest in this mode.

Sport and Performance settings are progressively better with whatever springs I do have. I'll say sport is my go-to for spirited, not pushing it driving. For highly spirited and/or track, I am happy with my springs and full performance FX3 setting as far as grip and response. Best of any C4 I have ever driven (my first was a base '94 383ci LT1 car with ZR-1 base suspension components installed for springs, shocks, brakes and ARBs).

so bottom line, whatever springs you choose, keep FX3 adjustable shocks!

Re: DRM coilovers & spring rates
 

"so bottom line, whatever springs you choose, keep FX3 adjustable shocks!"

I have bought new FX-3 shocks and a complete SuperPro bushing kit and will also replace the u-joint as well as new brakes, stainless brake lines and oil cooler lines etc.

Our goal is to try to get the driveability as good as new or even better because we want both comfort and control. New custom built wheels and new tires are also parts of the revamping we have planned. The coilovers will improve both the looks and the performance.

Sent from my SM-G955F using ZR-1 Net Registry mobile app

Re: DRM coilovers & spring rates
 

I've done this twice here are my recommendations


Total Poly Body bushing kit (Prophane kit)
Poly Sway bar links and end links etc etc
Guldstrand Front Sway bar relocation kit (Carter200 makes these as well)
Upper and Lower Ball joints (moog)
DRM Front coilovers with Hyper Coils 425 Spring rate fronts
DRM Rear coilovers with Hyper coils 275 Spring rate rears
Rear dog bones replaced with Heim joint links. The standards dog bones will not fit due to the springs.

Car handles well with stability, Does not wander. Very satisfied with the result. And no FX-3 lights. This build is solid.

Re: DRM coilovers & spring rates
 

Thes spring rates are etched into the top of the spring. These are mine before I had them sandblasted and powdercoated because they were looking worse for wear.

Re: DRM coilovers & spring rates
 

That's where mine are as well. They are not visible when installed but clearly marked on the top of each spring. Chances are if you bought your car from any member in this community this information has been shared for about 20 years on the optimal spring rates. 425/275

Re: DRM coilovers & spring rates
 

I am running 425/300 Hypercoil springs on mine. My FX3 shocks also have the
Maracca(sp?) valving. I would also recommend Poly bushings all around. I would also add, that the No Flex chassis stiffening system helps reducing chassis flex and that translates into the car handling flatter and with a feeling of more grip in combination with the Michelin PS4S.
I pretty much use Performance as an FX3 setting unless my gf is with me. I put it in Tour then.

Re: DRM coilovers & spring rates
 

I had to look it up as well Dom "Moraca Valving" is the correct name.