Eaglerulez

So I've been reading a ton of threads about suspension upgrades lately, but am a little confused as to wear to start exactly.

I have a 2004 Black Coupe with the F55 MSRC suspension, and Sumitomo HTRZII tires.

The HTRZII tires are fairly new as they were just installed when I purchased the Corvette (which was about 3,000 miles ago).

So far, I love my Corvette and think it is a fantastic car through and through but I feel like I am missing something in my suspension. For instance I used to drive a 2012 V6 Camaro to work everyday and I now do that run in my Corvette. In my Camaro I was able to basically hit turns at the same speeds as I do in my Corvette, but the big difference is that the Camaro definitely had some more body roll because it is a taller car, but the Camaro for some reason felt more confident in corners.

In general, I think my Corvette's suspension suffers from being "floaty" in the sense that it will handle turns fairly well, but for some reason it does not feel connected with the road and because of that it is hard to feel super confident when taking turns with it. The car isn't exactly "sharp" like I was expecting/hoping it would be.

Here is what I am confused with:

Most threads recommend upgrading the tires as the first big thing for the suspension. Though my Sumitomo's are cheap, I am wondering where they stand on the tire hierarchy and what a worthwhile upgrade for them would be. At this point, would my tires be the main thing that is holding the car's handling back?

My car also suffers from a squeeky front suspension which is especially noticeable over bumps. I figure I should just upgrade to a C6 Z51 sway bar with metal endlinks and poly bushings to see if that takes care of it. I am also wondering if these sway bars are going to help with the floaty feeling that I get when cornering.

My last question is in regards to my shocks. I know the F55 suspensions are notorious for leaking and going bad fairly early in a car's life cycle, and this car being 10 years old and all, it would not surprise me if these shocks were going bad. With that said though, I do feel a noticeable difference when switching between touring and sport mode, which leads me to believe that things are functioning, I am just not sure if the shocks are worn after all of this time. For the record my car has 50,000 miles on it.

I know the popular upgrade is to get Z06 shocks, which I am very tempted to do, but with me having a F55 suspension, I feel like doing this upgrade is a tad more expensive as it might just be easier to take the car to a shop to get the shocks installed so that way they can deprogram the F55 suspension option etc. Would the Z06 shocks help with that floaty feeling and road feel as a whole?

I will probably never ever track this car, but my uncle has a C6 Z06, and I like the idea of getting this car up to around 500 crank horsepower, and investing in some solid suspension upgrades so that way I could potentially give him a run for his money. Because of this, I am also considering a coilover suspension system since those systems generally have a better performance potential, and because I heard they do help with the "floaty" feeling which is something that is inherent with a leaf spring based suspension anyways. Since I plan on keeping this car for basically the rest of my life, I would not consider coil overs a waste of money even if I limit them to street use.

As a whole though, could anyone give me some thoughts and opinions on how to get this car feeling as sharp and connected with the road as it should be?

Thanks!

Dave-A

Eaglerulez

Haha tell me about it!

RFDrpm

Poly Bushings. #1 upgrade IMHO..

Eaglerulez

I personally have always liked the idea of poly bushings. It's an upgrade that makes complete sense to me. I know on Camaros their bushings were the weakest part of the car's suspension.

My only reservation is that they seem like a complete PITA to install, and I am not entirely sure if my bushings are what is causing the floaty feeling (though poly's could certainly help I think).

ezrider4u2

In each of the cars I've had the first things I changed were the shocks, the springs and sway bars in one visit.

These two items really changed the ride feel and handling for me. Once I did those, I could really through the car at corners with more confidence.

NukeC5

They are pretty good tires. Had them on another car. Sway bar upgrades and end links are the cheapest and easiest way to get some better handling. I'd start there. Poly bushing are a real pain. But worth it if you can do it.

Eaglerulez

Thanks for the input with the tires.

Yeah I was definitely thinking of starting with the sway bars.

Does anyone have any thoughts on replacing the shocks? Would doing some work on those be appropriate at this point?

Lt. Dan M.

Replacing the F45 in my 99 with C6 Z06 shocks. Already put C5 Z06 sway bars with stock bushings on it. That alone made a big difference. Only changing the shocks because they are noisy and I think they are dead.

racebum

tires are garbage, that would be the #1 thing i would change

as for suspension, poly bushings are a mixed bag. while they seem to work well on sway bars they go to hell quickly on lower control arms. i tried a set on an old daily driver and before 40k miles they were so sloppy i could move the lower control arms by hand a good 1/4" what seems to cause this is the inner bushing rotates in the poly. with rubber, you just have flex, the inner steel jacket doesn't rotate or wear. this is why rubber lasts so much longer than poly. it doesn't grind itself apart

what i would do if i were you is

1. get a good tire like the re11 if you're on stock wheels
2. call vettenuts and buy a used take off suspension from a z06. the springs, sways, shocks, all 3 items, install that and have a balanced car

if they won't give you used shocks for 60-80 bucks you can just buy c6z shocks which are similar to the 04z shocks but cost less. shocks usually should be changed out at 10 years of age so i wouldn't want to pay very much for any oem z06 shock even if they are low mile.

if you do this you should have an average skidpad of around 1.05-1.10g and peak transitions north of 1.25g on a warm day with decent pavement, car will also be a lot more responsive

MSG C5

I went old school with my setup. I installed C5 Z06 sway bars on my 2004 vert after I swapped out my OEM wheels and ditched the run-flats. I then installed Koni FSD shocks and an Elite Engineering tunnel plate with thermal abs. The car corners like it's on rails with no body roll as the Konis really plant the car on the road.

phil hunter

I upgraded my 2001 with C6 Z51 sway bars & metal end links. I did not change the shocks since I have the F45 shocks with only 17,000 miles on them and did not want to deal with reprogramming the car by switching to C6 Z06 shocks. I also switched to C5 Z06 wheels with Nitto Extreme II 275 40 17 tires up front and 305 35 18 tires in back. The sway bars, wheels and tires made a MAJOR difference in the handling of my car. I am now pretty happy with how it handles. When one of my F45 shocks goes bad, I'll upgrade to C6 Z06 shocks.


Phil

ScumOne

Eaglerulez, I've got a 99 C5 with the F45 and an 04 with F55 magnetic ride shocks.

The 99 F45 died after 15 years. I put in the Z51 sway bar kit, and MOOG metal end links in mine. It made a nice difference even with the F45 shocks, but they started to leak soon after the sway bars went in. I had those deprogrammed, and put in Bilstein Z51 version shocks. That REALLY tightened up the ride, and you could tell the old F45's were shot since the ride height came up about 3/8" in front.

I no longer bottom out on pebbles with the front air dam, and it's very tight in corners now.

When my 04 F55 go out, I'll be doing the same upgrade to them.

The whole suspension upgrade on the 99 (Z51 bars/bushings, MOOG end links and shocks) cost me around $1200 total.

Just to replace the F55 magnetic shocks will set you back close to $3000, plus labor.

Hope that helps you decide what to do. It sure was an improvement on the 99, though, it outhandles the 04 in my opinion...even in the sport mode.

spdislife

Poly is a lot of work and will wear quicker than rubber. Heavier sways and springs will give you the biggest bang for the buck.

I run the T1 suspension on my 04 Z since it's primarily a track car. I have the original Z06 springs, sways and shocks for sale if you're interested in a rather inexpensive upgrade. Just PM me if you want more info.

Mike94ZLT1

Go for the gold and just get it over with. LG GT2 coilovers. After dicking around with different shocks and springs, and finally getting coilovers, I wish I did them so much sooner. Yeah, they're pricey but they're so worth it. Easily one of my favorite mods.

racebum

strongly suggest you take him up on this offer OP, well, provided the price is decent

this is already a balanced setup that won't require you trying multiple bars or springs to find the under/oversteer combo you're after

olbear1962

100%.
Best suspension mod I ever did!
Upgrade the sway bars as well.

racebum

and with bars you're at what? 2750 shipped for the G2 coils with g1 bars?

full take off z06 setup is around 400ish

i guess it's the op's fault for not throwing out what he wants to spend

Eaglerulez

First off, I just wanted to thank everyone for their input and opinions. It is all very helpful and incredibly enlightening.

I think my first step will definitely be getting some kind of sway bar. Probably the C6Z51 bar because it is so cheap, but that may change depending on what happens with the rest of the suspension.

So here is what I am considering.

The car will basically never see the track, and it will almost never see speeds past 100mph. With that said though, I really do want to be able to throw this car into a turn at say 30-40mph and to just know that it is going to stick to the road and to feel nice and confident when making that turn. I guess another thing that concerns me about my car at the moment is that when I do go over a bump say when turning into an on ramp, it feels like the whole car rattles and vibrates (whereas say on my Camaro only the side hitting the bump would be affected), and that is an unnerving feeling that I want to get rid of.

I read up on some threads comparing coil overs and and leaf spring setups. The big thing that got my attention when it came to coilovers was that almost everyone said that their car definitely felt more independent when going over bumps and the like, and that this made things more pleasing.

The counter argument that the leaf spring proponents had was that these "improvements" were attributed to the fact that these drivers were also getting their cars aligned, and basically putting on better dampers than what came stock so that those improvements was going to happen anyways, even if those drivers were still using leaf springs. A few people were even saying that with upgraded leaf springs, shocks, and sways, their car basically had perfect handling, it was just at the 160+mph mark where the coilovers started to really help.

So really the question is: For those of you with Z06 shocks and either a Z06 or stock leaf spring, are you still feeling your whole car vibrate and move when you go over imperfections on the road? Is your car feeling planted and connected to the road enough to feel like you can take turns very aggressively?

As for how much I want to spend, I really don't know what the answer is. As I said, I will be keeping this car for a very long time, so spending $2700+ on coilovers could be worth it to me if it means I am going to LOVE the car's handling. But if spending $400-$600 on upgraded stock parts + whatever is needed to install and align, is going to get me feeling satisfied, I am all game.

I just don't want to invest in upgraded OEM parts and then have to spend more money on coilovers a couple of years later.

Thanks again for all of the thoughts!

spdislife

Thanks for the endorsement. 400.00 plus shipping would take it.