Eibach + KYB GR-2 = trouble?

[steve91tt]

I am looking for new springs and struts for my 1973 240Z. I would like to keep the ride as close to stock as possible but unfortunately stock springs are no longer available. In reading old posts the closest thing I have found to stock is Eibach pro springs with KYB GR2 struts. However, MSA recommends against this combination because the lowered eibach springs will shorten the life span of the GR2's.

Can anyone comment on the longevity of the Eibach/GR2 combination?

[Arne]

I suspect you will hear from several people with this combination who have not noticed a problem. While I do not have personal experience with this package on a 240Z, I do know this:

1.) KYB specifically says NOT to use GR-2s with lowering springs. If they determine that the inserts were used with lowering springs, the warranty is void.

2.) I ignored this warning in the past on a previous (non-Datsun) car, and the strut inserts were badly worn (bouncy, no rebound control) in less than 15,000 miles. YMMV, of course.

[steve91tt]

1.) KYB specifically says NOT to use GR-2s with lowering springs. If they determine that the inserts were used with lowering springs, the warranty is void.

2.) I ignored this warning in the past on a previous (non-Datsun) car, and the strut inserts were badly worn (bouncy, no rebound control) in less than 15,000 miles. YMMV, of course.

Arne,

I have read many posts that you have written in the past about the suspension on the 240z. Given the inability to find springs with stock rate and drop and the inability to get the KYB's to reliably work with a drop spring. What spring/strut package would you currently recommend for as close to a stock driving experience as possible?

[Arne]

Do you still have your original stock springs? If so, are you certain that they need to be replaced? Is the ride height still close to stock? If so, the springs are probably fine and all you need are new inserts, and the KYBs would be fine. I'd only worry about replacing the springs if the current set are sagged more than 1/2".

[steve91tt]

Do you still have your original stock springs? If so, are you certain that they need to be replaced? Is the ride height still close to stock? If so, the springs are probably fine and all you need are new inserts, and the KYBs would be fine. I'd only worry about replacing the springs if the current set are sagged more than 1/2".

The rear of the car sits very low (can't see the top of the wheels) and the suspension groans and creaks in the rear. The front seem fine

[Arne]

OK, it sounds like the rear springs at least are shot.

I'm not aware of any new springs in current production that are similar in ride height and spring rate to the stock 240Z springs. The current aftermarket springs all lower the car at least an inch, except for the Arizona Z springs which are about stock ride height but considerably stiffer spring rate.

To maintain a ride similar to stock, you will need either stock or only slightly stiffer spring rate. You could watch for a set of used 240Z springs, but there's always the risk that they may not be all that much better than the ones you have on the car now.

The other thing you could try to find is a set of the Nissan Euro Stage 1 springs, either original or a set of the reproductions that were available 2-3 years ago. I have the repros on my car with KYB and the ride/handling combo is quite nice. These springs do show up in the classifieds here or on eBay now and then. They need to be cut down some for use on US spec cars with gas shocks, but done correctly they give great daily-driver results.

[bpilati]

Actually we had stock springs made and sold by Courtesy Nissan a few years back and made it known on this site. I believe they were all sold. We also had Euro Stage I springs made, you might ask around about those. They are suppose to be 15% stiffer than stock and maybe 1/2" lower.

[GreenZZZ]

I wouldn't be surprised if most cars replacing nearly 40 year old springs, insulators and spacers with Eibach springs and Nissan insulators/spacers had the ride height raised, not lowered. Might be a good poll question for the forum.

[Arne]

Actually we had stock springs made and sold by Courtesy Nissan a few years back and made it known on this site. I believe they were all sold. We also had Euro Stage I springs made, you might ask around about those. They are suppose to be 15% stiffer than stock and maybe 1/2" lower.

Both the repro stock replacement and the Euro Stage 1 springs have been sold out for some time now - a couple of years, perhaps.

The official line on the Euro springs was that they were ~10% stiffer spring rate than the stock, and 10-15mm lower ride height.

The reality was much different. While the spring rate part seems correct, in real life the Euro 240Z must have had different strut tubes, as the Euro springs actually raised the ride height by 20-25mm. Most of us using them (like myself) ended up cutting a couple coils off of each spring.