BC ER, SPL Install and Adjust

sandersd

So I reinstalled the shocks and went to fill up. After I pulled up to the pumps but before I started filling I measured and both sides = 26.5". After I filled up both sides measured 26.5".

Went back home and measured and the 1/2" diff was back. So all that was for nothing. Moral of the story is make sure you have a flat and level area to take your measurements.

Well, at least I am intimately acquainted with my suspension setup.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

GSS138

Similar problem when I was doing this-I have BC BR's and 12k/11k swifts. Some of it can be the surface, also if you let your car down off the lift and don't move it or roll it out, you can expect to lose a good 1/2" once you have rolled out the binding.

Also everytime I have removed the top 3 nuts and put them back on, clunk. I drive it for a day or 2 or 3, retighten the bolts and find I usually have sometimes almost a full turn of play in them.

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Current Mods: Vorpal Weapon +5.

sandersd

Alignment shop was booked for last Saturday so I'm planning for this Friday. Still have an annoying low speed rattle/klunking. Doesn't seem to be localized from one place so I still have to sort that out.

Was driving home Sunday from the grocery store, went over railroad tracks and something sounded like it broke, then a dragging sound. Limped around the curve, turned left, drove 100 yards and turned into a parking lot.

I'm thinking "Geez, now what?"

I look at the rear - nothing. I look at the front - nothing. I look under the car and there's a branch jammed into the undercarriage and dragging on the ground.

Relief...

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

Robert Yuras

You plan on corner weighting the car?

sandersd

Yes, but I want to drive it for a while so I have something to compare it to.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

sandersd

Installed the adjustment extenders that came with the shocks. To mark the place to drill the holes I took a sanding roll bit from my Dremel set, snipped it to an appropriate length and inserted it in the piece that fits over the adjustment knob at the top of the shock.

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Installed the cap on the shock, then bolted the shock into place. The pointed piece was just long enough to dent the underside of the plastic trim so I could see where to drill.

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I used a 1/4" bit to drill the hole.

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The hole is just big enough to fit the extender shaft and tube through. I trimmed off excess length so they would clear the hatch by about an inch.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

GSS138

Think twice before you corner balance it, kind of a waste of money at least in some people's opinions unless you have replaced all of your compliance bushings. I know a few guys in formula D that say it is a complete waste of time and money to do it on a car that has compliance bushings in it still. They told me that if you have the ride heights to the millimeter, you are as corner balanced as you are going to get. This was sort of surprising to me but they swore by it. Told me that even if I got corner balanced, as soon as I took a turn it wouldn't be corner balanced anymore.

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Current Mods: Vorpal Weapon +5.

Robert Yuras

Sorry, but I disagree 100% - ride height has nothing to do with corner weighting. Ride height is certainly important, but its only the base of the foundation for weighting. If I came and put a 200lb weight on the passenger seat of your car, you'd hardly see a ride height change. However, you'd see a corner weight change. In fact, I could shift that 200lbs all over the car and you'd hardly see a ride height change. The 200lbs would make a dramatic corner weight and cross weight difference though.

Of course you aren't corner balanced through a turn, the car is turning and throwing weight all over the place. However, when the car comes back to neutral, it better be back to normal - otherwise you've done something very wrong.

Sorry, but there is not logic in that "formula D" answer, much like the series itself.

GSS138

I was skeptical about it myself at first but the more I think about what he said the more sense it makes.

The guy sets up, sponsors, and is a crew chief on a professional race cars that have won and are competitive at a number of different levels, so I would put a lot of weight in what he told me.

Specifically he said ballast the weight like you mentioned, set the ride height, you are done. I am not personally sure how that accounts for front to back, it definitely does not account for cross. But his point is that even if you balance it perfectly, because of the soft subframe and knuckle/control bushings, it is going to go out of whack almost instantly. He showed me our OEM bushings, they are very soft, you can depress them with your finger. I had a hard time believing it myself but the more I think about, the more I think he is right.

And I am no fan of formula D, I just go to his shop for tire mounting and to shoot the breeze. Like Formula D or not those guys know more about setting up a car than probably anyone.

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Current Mods: Vorpal Weapon +5.

sandersd

Still clunky over bumps so been doing some research. Many threads here and elsewhere regarding clunky coilovers, BC or others.

Things to check:

1. Top nut on shock - tighten
2. Play between lower shock mount and OEM mount - add spacer
3. Preload on rear spring (8-10mm per BC) - verify and correct

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

Robert Yuras

All springs should have preload. If they don't, they will bounce during sudden transitions and make a clunk. You should be able to keep your ride height, but adjust your preload if the coil over has a threaded shock body.

sandersd

The fronts had preload set as shipped. The rear had preload set at 5mm during installation. What I'm going to do is jack up the car, remove the wheel, and measure the preload with the suspension weight unloading the spring, then bump up the preload to 10mm per my discussion with BC tech support.

I believe as you said above that, due to the amount of play in the shock mount, the preload is moving between 5mm and <0mm as the suspension moves through its travel, allowing the spring to strike the lower/upper perch with a clunk. This time I will be sure to recheck after I release the jack supporting the lower spring seat and apply pressure in each direction to verify it remains at 10mm preload.

I don't expect the top nut to be loose - I'd be surprised if it was. I did notice the width of the lower mount was wider than the OEM mounting point and this might account for the rattle, but not the clunk. If it seems significant enough I'll add a washer/spacer to achieve a snug fit.

Some have also complained that the locking rings have loosened over time and their solution was to add blue Loctite to keep it from backing off.

There are only so many joints in the rear (or front) suspension system. It's just a matter of eliminating them one by one till the culprit is found.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

Spooler

Corner balance it first, then have the alignment done. That's the point of getting coil overs, to be able to balance the car.

sandersd

My primary motivation is to be able to lower the car and maintain full suspension travel on linear springs. I agree corner balancing is necessary to take full advantage of coil overs capabilities and something I certainly intend to do so, but I want to compare the handling and performance between balanced and unbalanced, so I need a frame of reference.

It's just to satisfy my own curiosity. But you're right, if one is into performance corner balancing is fundamental. If one is more into styling and profiling then corner balancing is not essential.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood

sandersd

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Very disappointed in the workmanship at EVS Motors so I will find a different shop for future work and corner balancing. I want to speak with the shop manager before I get into specifics.

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2014 370Z NISMO -- HKS Hi-Power Exhaust -- Swift Springs -- BC ER Coilovers -- SPL Suspension Components -- Nismo R-Tune Intake -- Seibon BD CF Hood