Can 510 coupe use FRONT 240Z coils in rear?

[guyster]

I thought I read about lowering a the rear of a 510 using 240Z FRONT coil springs, but I can't find the thread. Thanks for your help. (And please don't give me the "here's how Google works" middle finger.)

[datzenmike]

No.

 

510 stock rears are around 300 to 350 lb/in. No Datsun known runs a front spring that hard.  Dodge D-50 front coils will work. Look it up in The Dime Quarterly  Google Docs.

[flatcat19]

No. Because a 510 coupe is not a real thing. 

[guyster]

^^ Well, aren't you pleased with yourself? Yes, not a coupe, a 2-door. My other datsun is a coupe, or fastback. Your call.

[flatcat19]

:yawn:

[guyster]

Zzzzzzzzzz. Bored? Stay off my thread. Thanks

[datzenmike]

Dodge D-50 coils swap story is Volume 9 issue 2 page 15 of The Dime Quarterly on Google Docs. A good read. They'll work on that coupe too.

[guyster]

Thanks Mike. That's very helpful. Looking forward to the read!

[guyster]

Dodge D-50 coils swap story is Volume 9 issue 2 page 15 of The Dime Quarterly on Google Docs. A good read. They'll work on that coupe too.

 

I've read the documents. My last question before pulling the trigger is ... am I gaining anything over the stock spring? If so, I'll stick with those, but if these are going to help the car handle better, then I'll go for it. Thanks!

[datzenmike]

Generally cars have a softer compliant suspension including plenty of road clearance to please the greatest number of buyers. 'Soft' springs and high ride height make a car lean to the outside on 'performance' turning and nose dive on 'performance' stops. By performance I mean pushing the car to its maximum handling abilities.

 

Lowering the vehicle's center of gravity makes it much more stable on corners and reduces weight transfer on hard stops but again it is closer to the ground which has it's own disadvantages. To reduce the chance of bottoming the under side components a firmer spring should be used. This also reduces body leaning on turns and nose diving when braking. 

 

According to the DQ text the stock 510 rear spring rate is 132lb/in*. The uncut D-50 front coil is 155lb/in. (only a 17% increase and from my experience on my 710 a 50% increase is much better and if anything still conservative) Trimming 1/2 coil off the D-50 spring raises the spring rate to 170lb/in or almost 30lb/in. This seems a reasonable amount to start with and besides once cut you can't put it back. The car may now sit lower or too low so fit rubber shim spacers to adjust. Never trim a coil spring to set the ride height. The shorter the spring the higher the spring rate. By the time you get low enough it may be too firm a ride for you. The chance of hitting your perfect ride height AND amount of firmness is ... unlikely.

 

Two last things, if you like the slightly lower ride height you will have to do something to the front to match it. Not just the height but the spring rate. Stock strut coil is 89lb/in.

 

* Because if the way the 510's rear spring is cantilever mounted, (not over the rear wheel) the spring must be 3.8 times stiffer to get a perceived stock 132lb/in at the wheel. The stock rear coil is actually about 500lb/in if measured by itself.

[guyster]

Very clear explanation. Thanks

[shacks510]

800lb Nissan Comp springs or nothing :D

[datzenmike]

800lb/in would feel like 210 at the rear wheel and this is about a 58% increase.