WHY LHD cars have exact same springs as RHD cars?

[kats]

Hello,

I have a question, I looked up earliest parts catalogs both LHD and RHD, springs are exactly same for both.(except Z432,of course this car is RHD only)

I thought the reason of front springs are different right side and left side because of the driver and related systems weight( steering/pedals/guages e.t.c), but seems not.

Because of what? I think LHD should have inverted springs right side and left side.

All S30 have longer spring on the right side than left side, they become same length when installed.Please see attached picture.

Long spring means soft(confortable) ? or stiff ?

If it means soft,

I can see this is reasonable for RHD cars, but I do not get it for LHD cars.

Am I slant little bit to the driver's side when I am in the each car's (LHD and RHD) cockpit?

Any thoughts would be appreciate.

kats

Edited June 15, 2011 by kats
add some text

[John Coffey]

I've corner weighed a stock LHD 1971 240Z and the right front is heavier then the left front with a driver and passenger in place (actually 125 lb. sand bags). Removing the battery balanced the front weights.

[Arne]

I've always heard it was the battery, alternator and starter all on the right side that required the longer RF spring, not the weight of the driver. The passengers sit far enough towards the rear wheels that I suspect their weight has more effect on the rear corners than the front.

[HS30-H]

Kats,

Damper rates ( bump & rebound ) are different between north American market Export 240Z and Japanese market Fairlady Z & Fairlady Z-L.

And 'European', UK, Australian & NZ market Export 240Z are different again.

Spring seat heights are different too!

Complicated subject......

Long spring means soft(confortable) ? or stiff ?

I think it means neither. Key point is compressed length with car level and stationary. Aim was to level up the car. Spring rate ( 'hard' / 'soft' ) is a different issue.

[LeonV]

Other dimensions held constant, a longer spring will have a softer rate.

[spitz17]

This is interesting to know. I was thinking of cutting and welding on threaded collars to my stock JDM 240Z-L strut housing for coilovers. Now that I know they are different, I best source a set of USDM strut housing.

[HS30-H]

Other dimensions held constant, a longer spring will have a softer rate.

I'm trying to point out that the car needs to sit properly ( level side-to- side, and not too much rake end-to-end ) quite apart from the actual spring rates, but still taking them into account. Does that make sense? Probably not.....

[kats]

Thank you All, thank you.

I should not say all S30 have same , thank you Alan.

I should say in terms of early S30s,I looked up Oct 1969 LHD 240Z parts catalog, Dec 1970 RHD 240Z parts catalog, Mar 1970 Fair lady-Z parts catalog.

Springs are all the same except Z432. (for RHD 240Z, there is an option though)

Shock absorbers are all the same even Z432.

Some point in 1970, changes were made.

Mr.Miyazaki( S30 test team, not test crew in the U.S. late 1969) show us some reports, Euro 240Z was finally settled in Mar 1971.

The one interesting reports there,it says

Apr 1970 : at Yatabe test circuit, Euro version (HLS30Q) project started using HLS30U( US spec) they found bad cross wind stability in high speed cruising

Jun 1970 : Euro version was set. It says this suspension set up is same as Z432, same spring rates and same front / rear stabilizer.Shocks are the same of all the S30. At this point, rear spoiler only.

Aug 1970 : Above Euro car(s?) was shipped by boat to DATSUN Netherlands

Nov 1970 : DATSUN Netherlands tested and reported feed backs.They said

"The side wind stability is Very Bad. This is caused by the following points"

1,The center of gravity is a bit too high

2,Too much body roll caused by bad shock absorber

3,Roll bars in front and rear are too light

After this reports, the team took immediate action.First, they took a rally car Monte spec, then tested.

to be continued.

kats

[kats]

Like Arne said, right side of the car is heavy. Especially Export 240Zs have a big battery.

I thought L24's intake and exhaust manifolds and carbrators are heavy, but maybe not that much to compare the right side.

Z432's S20 engine is right side heavy, all the things installed right side.On the left side, only stainless exhaust manifold and small battery.

We are sitting almost in front of the rear tyre, yes(^0^)

kats