should all 240's have rear sway bars

[Arne]

Thanks, Carl. That pretty much confirms what I had heard. I think the Stage I will be just about exactly what I am after.

[SteveInOakland]

I'm riding on my new stock springs, they're great!!! I ordered a set of the Euro springs too.

Dramatic difference from the old tired springs? Any idea if the car rides significantly higher?

Thanks,

Steve

[wa5ngp]

Wow, if had wanted to troll I couldn't have done a better job than I did with my question about a rear sway bar. At least now I know not to order the rubber parts for it when I get all the other stuff. If I get more serious about auto crossing again I'll probably add one to the rear. It does seem odd that the USA version would not include one since I would assume that a rear bar would not add to ride roughness. I suppose that Datsun just didn't think we cared with all the big wide highways etc.

tks for all the comments.

Don

[bpilati]

Dramatic difference from the old tired springs? Any idea if the car rides significantly higher?

Thanks,

Steve

I would not say significantly higher, but at least noticeably higher in the rear from the sag it had. My wife stated she could see a difference while following me. Don't worry, your Z will not look like a 4x4.

[Carl Beck]

Hi Don/Arne (everyone):

Don originally said; ..."An opportunity to do something better".... it may be Don. Better is a relative term. Better than what? Better for what use?...

"Better Handling".... Here again the real question is; better for what driver, under what conditions?

Should your 240Z have a rear anti-roll bar (ARB)? That depends on how you want the car to respond and/or ride under the conditions you plan to use the car. It also depends on how you like to drive. That is to say "a good driver handles the car", only when it is not responding the way the driver wants it too - does he fine tune the suspension to meet his needs.

Almost everything in a vehicle is a trade-off of one parameter against another. In stock form, our 240Z understeers when pushed hard into corners. A car that understeers might plow nose first off a corner if the driver pushes too hard, but one that over-steers is likely to spin-out of control completely. In the US, cars are considered to be "safer" ie. "better" if they understeer a bit, and most of the cars sold in the US are designed to do just that, as they leave the factory.

In stock form our 240Z gives it's driver lots of "margin" and lots of "warning" before it looses adhesion in a corner. (the body rolls, tires squeal and it starts to plow forward). Add that larger front and rear anti-roll bar, stiffer shocks, stiffer springs, wider wheels and better tires..... and it will corner at a higher rate of speed and handle in a more neutral manor... but the trade-off is that when it exceeds it's limits of adhesion...it will also let-go with what seems like "No Warning" at all!

So which is a "better" handling car for the average street driver - one that gives you lots of warning and which you can retain control of, or one that you can easily loose control of as it lulls you into that corner at even higher speeds?

IMHO - the average person driving a Datsun 240Z back in the early 70's - won't have the nerve to push it to it's limits, and they certainly don't need to start fine tuning it's stock suspension, until they are able to control it at it's limits with its stock suspension. In other words, improve your "handling" skills first, then decide what fine tuning needs to be done to advance the cars capabilities to respond. (as has been pointed out there are lots of options in the fine tuning dept.)

If you are using the car mostly for High Speed Auto-X, club Track Days, or even weekend Road Racing.. then yes maybe that larger front and rear ARB is just the ticket. But it would make good sense in those cases, to take some formal drivers training, spend some seat time getting to know how your Z will now handle with its modified suspension... Get some seat time in, were you can spin off the track without serious damage to your car.... As you increase the 240Z's cornering ability, you reduce the time and warnings you had when it was in stock form, before it lost adhesion to the road.

Spring rates are another example of trade-off's being made. US Spec. spring rates were most likely the "best" for most US drivers, on US Freeways and Secondary Roads, as well as daily in-town driving. Where the car was used mostly as a second family car, or a highway cruiser (al la GT use). They provide a reasonable trade-off between handling and ride harshness. Stiffen them up a bit, if you want to improve your times through Mullholand Drive, but the trade-off will be a slightly harsher ride the other 98% of the time you are in the car.

Keep in mind that something like 94% of all 240Z's produced were sold in North America, and if I had to guess, I'd say that about 10% of those, were actually sold to Customers that could be considered "enthusiast" drivers, or who would actually use the car primarily for "Sport". DATSUN Competition Department existed for those enthusiasts, as did BRE/InterPart, BSR etc..

As close as I can guess, based on Alan's input in an earlier thread, about 3% of the 240Z's were sold in Japan, and based on other sources about 3% of the 240Z's were scattered among 5 different Countries around the world. I would suggest that those units were purchased 90% of the time or more, by sports car enthusiasts, not simply as second family cars. So we see Nissan fine tuning them for the niche market they were in, with slightly stiffer springs, 5spd.'s and lower rear axle ratio's. For these markets these items stock or optional, supplied "better" handling for the majority of their owners.

Going Auto-X'ing on the weekends?... Spend your money on better tires.. leave the rear ARB off. Install better shocks with the Euro Spec. Stage I Springs, a thicker front ARB and Torque Sensing Posi.. (my personal Best set-up - you driving style may vary).

The bottom line is, if you take the customer base, the driving conditions, and the most common use of the car into account - then I believe that the US got the "best" suspension set-up for the US Market, and I'm just as sure that the other countries got the "best" set-up for their Customers as well.

BTW - The original BRE Rear ARB is a more effective mounting method. It runs around the rear of the differential, and does not rely on the thin metal in the uni-body for mounting. I'm not sure who handles them now... Ground Control/Suspension Techniques used to..

FWIW,

Carl B.

Carl Beck

Clearwater, FL USA

http://ZHome.com

[SteveK]

BTW - The original BRE Rear ARB is a more effective mounting method. It runs around the rear of the differential

Indeed, there is a picture in my gallery

that shows the general idea, courtesy of Motormec car prep who used it on one of their rally cars.