taintedred07

iTrader: (1)

Has anyone gone from YYZ springs with koni strut inserts and koni rear shocks(my current setup), to BC coil overs?

Wanting to know if it would be worth the swap for:

1.) Lower stance(just enough to eliminate wheel gap)
2.) Stiffen the rear to prevent any squatting on hard acceleration

I haven't heard of anyone at this power level with a setup like this on yyzs + konis. While I have the upmost confidence in this setup, I'm trying to gather info and experience to determine what would be best for me.

I plan on making the jump to light speed with my batmowheel s259et, shooting for 500-600whp(depending on tires/fuel) and want to have a competent setup to help putting traction down + maintaining confidence in the control and handling of my cobalt at that power level in the street.

Current suspension/drivetrain mods:

Yyz v2
Koni strut inserts
Koni rear shocks
Rotated front/rear trans
mounts(powell)
Trailing CABs
Moog endlinks (may upgrade to powergrid)
4.45 trans
Gmpp clutch kit

****going to get regardless: hardcore/xxx rear sway bar****

Important notes:
-this is strictly a dd for the time being
-street driven only

Basically, would it be worth swapping to coil overs at that power level.

Thanks

blueLNFftw

iTrader: (16)

Is the GMPP really going to be able to hold that for any length of time?

taintedred07

iTrader: (1)

I don't see why not, it's been holding 400+wtq fine and others have used it on their builds in that range. I'm also not going to be launching the car anytime soon, just dding with occasional roll racing.

yellowsupercharged06

iTrader: (3)

hey has this already lol, its guna be a clutch job sometime in the future though.


as for the suspension setup, ive always wondered this.

Infra has Pedders XA with R888 on his redline @ 550+ whp https://www.cobaltss.net/forums/whee...review-313928/


maybe powell can chime in on this one.



i think the tire is going to be the other sticking point.

taintedred07

iTrader: (1)

Exactly, I plan on upgrading to sticky tires when I put the turbo on, that's why I didn't mention a specific tire.

Infas had great success with his coilovers and r888s and that thread was very informative, so that's why I was wondering about staying with my yyzs.

As far as the clutch, I know this is asking for a lot but this is a dd so if it starts slipping at a certain powel level we'll just turn it down until it gets replaced ect Again, this isn't going to the track anytime soon.

Bass_Waves

iTrader: (24)

I sort of went with coilovers. Just due to powell being a auto x guru. I haven't read much on what he knows but I know I was supposed to run the yyz with v1 springs. Yet they are like unicorns. So next best thing. BC coilovers. My buddies and I have had a lot.of track time with the coils. Came out ok.
12.6 on a stock turbo lnf with exhaust,intake and tune. Drag radials.
So I am doing the Same. Since I'm playing with them. I went softer in front. Stiffer in back. Small reverse rake going on but seems to work.
Currently im.going for 550 to the wheels so come spring I'll let u know how the suspension reacts.

JapEatr

iTrader: (9)

my only concern with coils is maintaining decent stiffness and ride height while preventing the axle bind

taintedred07

iTrader: (1)

Well I don't think axle bind is much of an issue from what I've heard on a conservative drop, just to eliminate wheel gap. I could be wrong but it's more of a slammed issue from what I've heard.


I know the yyz and konis shine through the auto x/ road racing ect, just wondering if the lower center of gravity and overall adjustability of coilovers is worth it - for STRAIGHT traction during wot pulls ect.

JapEatr

iTrader: (9)

the rear spring rate is also key

taintedred07

iTrader: (1)

Yea I have this same thread on fb and Powell's been giving his input and he said there are no aftermarket springs that can equal yyz rear rates.

So I'm pretty content with staying with my setup.

hawkssoccer11

iTrader: (13)

i say go with coilovers just because it will be a stiffer ride and the weight transfer wont be too crazy. if your on 18s axle bind wont be an issue at all. im on 17s an decently low but not making the power you are but ive had the coilovers on for about a year now and no axle bind. def get those R888s lol they are so damn sticky and nice esp for roll racing lol all my friends who are making good power fwd and rwd are running those tires they swear by them

yellowsupercharged06

iTrader: (3)

i thought one of the coilover brands were making a special rate spring for us ... it may have been a 1 time deal but i thought i read that somewhere for a group buy.

Joe09SS

iTrader: (1)

Yeah stance 9k spring rates.

yellowsupercharged06

iTrader: (3)

how do those compare to the yyz's ?

InfraRedline

iTrader: (4)

I would say try out what you have first, because you already have them. If you want to switch it up after trying it out then that would be the time. I really have no experience with any YYZ's or Koni's or a combination of the 2, I've only heard good things. As far as a spring/strut setup I would think that would be about the best. I have had great success with my Pedders coilovers on my car coupled with my R888's, and I know that my B&G springs on stock struts would have struggled to put the power down because of all the weight transfer, but yours should be much stiffer. So I say try what you have an make your decision from there.

taintedred07

iTrader: (1)

That's what I'm going to do for now, whenever I piece together another kit with tires ect. Both the strut inserts and the rear shocks are adjustable so I'll have to play with those and see what I like I guess.

yellowsupercharged06

iTrader: (3)

I mean if u really wanted to, you can crank down the rear struts for race time and that should keep it from throwing the weight to the rear.

Viperoni

Don't CSS/IRL coilovers use regular coilover-type springs (2.5")?

JapEatr

iTrader: (9)

Viperoni, are you suggesting gettkng 2.5" diameter coils for another application that is closer to 9000 lb spring rate?

Viperoni

9k isn't 9000lbs/inch, it's 9000kg/mm. The conversion is approx 56x, so 9k springs are equal to about 504lbs.

A 2.5" inner diameter spring with both ends flat is a common coilover spring, and they're available in many different spring rates.
As an example, 2.5" ID 10" long Hyperco springs go up to 800lbs:
Hypercoil 2.5" x 10" Coil-Over Springs

Powell Race Parts

iTrader: (3)

^^^ exactly. Viperoni is right on. And the damping is the issue with any cheap ass coil overs. The shock cant damp that spring rate. But if you dont care about the ride, jack the back up and chain the front down with cables or chains and you will be set for drag racing. Better get a trailer ; it will be a horrible car to drive to the track. Hyperco 500 inch pound springs will be linear, best quality, cost about 80 dollars each. The coil overs will break soon enough but I imagine the trans will beat the shocks to it.

If you want to drive your car and go to the track here are YYZ. For best track performance you still would need to deal with the front etc but I am not sure you will go to the that trouble and like I said, the transmission will blow up soon enough. Drag racing is arguably the most difficult, most expensive mechanically sport known to Cobalts.

But still.
YYZ are rising rate. YYZ SPRING SPECS:
V.1
Blue pc finish, acid washed and media blasted.
Front: .540 wire diameter, nominal 12 inch free length. Variable rate, 138/265 lbs.
Rear: .512 wire diameter, nominal 12 inch free length. Variable rate, 108/250 lbs
V.2 December 2012
SPRING SPECS: v.2:
Blue pc finish, zinc phosphate prewash before powdercoating. Shotpeened before powdercoating and prewash.
FRONT:0.532” wire diameter (High Tensile Chrome Silicon spring wire), nominal 11.625” Free length. Variable rate 138/265#/in
REAR: 0.485” wire diameter (High Tensile Chrome Silicon spring wire), nominal 11.250” free length. Variable rate 105/325#/in
Trim height: compared to v1, drop additional 0.350-0.400”Front and 0.750” Rear
By comparison, OEM FE5 Cobalt SS Turbocharged springs are a constant rate of 158 lbs at the front, and variable rate 120/200 lbs at the rear. All other aftermarket springs (including OEM SS Supercharged, and OEM FE3 springs) on the market have less rate than the OEM FE5 TC springs, which were our benchmark for the YYZ springs.

InfraRedline

iTrader: (4)

We are talking about street use, I don't think he plans on doing much or any drag racing. Gotta keep that in mind. Something streetable that will still hook up is the key. I still say try what you have because you already have them, and go from there.