True Rear vs. Divorced spring (causes damage?)

scope22 · 02-24-2020, 08:12 AM

Quote:

Originally Posted by Brendan

True types are way easier to adjust than the divorced type. There aren't any real downsides especially if you are running relatively soft street rates.

If you are building the kit yourself, know that type set-ups will need to run a much softer rate spring in the rear than if you keep the oem set-up. if you are buying a kit off the shelf, that should already be taken into account.

Its my understanding that getting soft springs is the cause of the failure, if you hit something really hard and spring compresses all the way, the mounting point of the car will then take the rest of the force. I've been running fortune 500 coilovers for a while now, with stiffer springs and no issues (14k/12k) iirc.

Rusty · 02-24-2020, 02:44 PM

Quote:

Originally Posted by scope22

Its my understanding that getting soft springs is the cause of the failure, if you hit something really hard and spring compresses all the way, the mounting point of the car will then take the rest of the force. I've been running fortune 500 coilovers for a while now, with stiffer springs and no issues (14k/12k) iirc.

It's a combination of spring and valving. The oem set up has to use a stronger spring then a true style because of the leverage of the oem set up. If you use the same spring rate on a true style as the oem. You're over sprung.

Hotrodz · 02-25-2020, 07:40 AM

Quote:

Originally Posted by Rusty

It's a combination of spring and valving. The oem set up has to use a stronger spring then a true style because of the leverage of the oem set up. If you use the same spring rate on a true style as the oem. You're over sprung.

It is about wheel rate and because of where the spring located you have change the geometry so to speak and the wheel rate will be to high if you run the same springs as in a divorced setup. Ask me how I know!!! I did this with my Z and I had more offs and near offs at the track because I was way over sprung in the rear given a true setup over divorced.

16nz34 · 02-26-2020, 11:03 AM

Going with Fortune Auto 510's, true setup. Hyperco springs 14K front, 10K rear...my 2016 370Z is a full on track car and I have zero worries of failure. This baby has already been to WGI, VIR, LRP and many others and each have curbs that would rattle your fillings loose...no problems.

Hotrodz · 02-26-2020, 11:35 AM

Quote:

Originally Posted by 16nz34

Going with Fortune Auto 510's, true setup. Hyperco springs 14K front, 10K rear...my 2016 370Z is a full on track car and I have zero worries of failure. This baby has already been to WGI, VIR, LRP and many others and each have curbs that would rattle your fillings loose...no problems.

I don't know if you are running any aero or not as I have a 5" front splitter and a APR gt300 rear wing. I had my FA coilovers rebuilt to 510 with Hyperco 800lbs front and 350 rear springs. I still think your rear springs are too stiff. The should be closer to 7k. You find them to be more compliant going over curbing and bumpy tracks. You may struggle with oversteer if your rear springs are over sprung.

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16nz34 · 02-26-2020, 01:26 PM

Quote:

Originally Posted by Hotrodz

I don't know if you are running any aero or not as I have a 5" front splitter and a APR gt300 rear wing. I had my FA coilovers rebuilt to 510 with Hyperco 800lbs front and 350 rear springs. I still think your rear springs are too stiff. The should be closer to 7k. You find them to be more compliant going over curbing and bumpy tracks. You may struggle with oversteer if your rear springs are over sprung.

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No aero at this time...I wouldn't do aero unless I had a wind tunnel to test it in and some professional input...bad or "guess" aero could make things, much, much worse than anything I can do on my own with the suspension.

The current FA 510 setup and spring rate was professionally recommended...I provided a lot of technical detail to FA and they came up with the starting spring rate...we'll see how it goes once things thaw around here...trust me, I won't be heading out onto the track with brandie new coilovers and be whaling on the car...at least not until I know how it responds and reacts.

Hotrodz · 02-26-2020, 03:17 PM

Quote:

Originally Posted by 16nz34

No aero at this time...I wouldn't do aero unless I had a wind tunnel to test it in and some professional input...bad or "guess" aero could make things, much, much worse than anything I can do on my own with the suspension.

The current FA 510 setup and spring rate was professionally recommended...I provided a lot of technical detail to FA and they came up with the starting spring rate...we'll see how it goes once things thaw around here...trust me, I won't be heading out onto the track with brandie new coilovers and be whaling on the car...at least not until I know how it responds and reacts.

LMAO, you have not been on the forum very long and made a handful of post. I am not sure how long you have been tracking and your depth of knowledge with the 370z platform but your post in naive. First off you don't need to do a wind tunnel for all things aero. It is common knowledge that lowering the car and adding a from splitter and having some type of rear spoiler will help. I have been dealing with FA for several years and their product is nice but some of the advise is suspect on spring rate recommendations. Lastly, because of my aero I reached out to a aero consultant to help me dial in my aero and suspension. There is a thread dedicated to that discussion in the track section of the forum if you want to increase your know and whole lot of discussion about spring rates for divorced versus true type setups. Therefore my advise is not without consulting a professional or others on this forum that have equally as much knowledge. So the rule of thumb is with a true type setup you don't want your rear spring rates to be much more than what you have for a divorced OEM spring rate, maybe slightly higher. Good luck and I hope you don't have a negative outcome because your rear spring rates are too stiff. I think the track is the best place to try out your new coils as it is a controlled environment and on the road if things go wrong it could be fatal to you or someone else. I hope it all turns out the way you want.

Rusty · 02-26-2020, 06:20 PM

Quote:

Originally Posted by Hotrodz

I don't know if you are running any aero or not as I have a 5" front splitter and a APR gt300 rear wing. I had my FA coilovers rebuilt to 510 with Hyperco 800lbs front and 350 rear springs. I still think your rear springs are too stiff. The should be closer to 7k. You find them to be more compliant going over curbing and bumpy tracks. You may struggle with oversteer if your rear springs are over sprung.

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02-26-2020, 11:03 AM	#4 (permalink)
16nz34 Base Member Join Date: Feb 2019 Location: NH Posts: 9 Drives: 16 Nissan 370Z PW M6 Rep Power: 8	Going with Fortune Auto 510's, true setup. Hyperco springs 14K front, 10K rear...my 2016 370Z is a full on track car and I have zero worries of failure. This baby has already been to WGI, VIR, LRP and many others and each have curbs that would rattle your fillings loose...no problems. Rusty likes this.

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