I need springs what can you reccomend for rate?

[cyrus]

I need springs what can you reccomend for rate? The car is 2550 wet no driver.

 

f/r = 52/48 when done.

 

406RWHP

 

245/40/17 kumho esta 700, treadwear 50 (all corners)

 

usage track/street/auto-x/drag (in order of importance, most importance ->least.)

[jt1]

I've got 250F/275R with Illuminas. With the shocks on 2, it's very firm but not teeth chipping level on the street. Fine for short trips, but would get old on a long trip/rough roads. With the shocks on 5 it works well on the track, probably as stiff as you want without major chassis stiffening, which I don't have.

 

John

[johnc]

200F/225R with Illuminas and 25mm front and 19mm rear anti-roll bars.

[auxilary]

coilovers, 10" x2.5" springs, front 225/rear 250, tokico illuminas. use smaller rear sway bar. illumina shock adjustment plays a big role in controlling rebound, you WILL feel the difference.

 

edit: listen to coffey, he knows better than i. my car was 2400 even in stock form with 200 all around, and it was quite a stiff ride

[blueovalz]

I had a great ride for the street with 200 front and 235 rear.

[Drax240z]

I'm running a 200f/250r split with no rear bar and a 1-1/8" front bar, and using illumina's for damping. Works well, but I still need some fine tuning, I think a 1" front bar would help. John's suggested setup would work very well. (I ran 200/225 for a while, but had too much understeer going on with no rear bar... so I added some more spring)

[cyrus]

200F/225R with Illuminas and 25mm front and 19mm rear anti-roll bars.

 

Where can I get the sway bars in millimeters?

[johnc]

19mm = ~3/4"

25mm = ~1"

[Clifton]

I run 250f / 280r with Konis on the street car. Nice ride. They only dampen on rebound though. I've been in other Z's with similar spring rates that were much stiffer from too much dampening.

[gramercyjam]

300# springs + 1" way bar is not enough.

 

 

[johnc]

300# springs + 1" way bar is not enough.

 

Not enough for what?

[gramercyjam]

Not enough to be the quickest.

[auxilary]

yeah, but if you look at his order of importance, he wants to be able to take it to track days, and take it out on street on weekends.

 

I don't think 300lb springs would be comfy for street

[johnc]

Building a good track/autocross/street/drag racing car is basically impossible. The car will not be good at any of these uses when compared with a car built for a single use. If you're lucky, you're somewhat uncomfortable street car will be a mid-pack track day car, a back of the class understeery autocross car, and a resonable drag car with launch and traction issues.

[auxilary]

or, he could invest in several sets of springs and make it easier for specific events?

[JMortensen]

or, he could invest in several sets of springs and make it easier for specific events?

 

Problem there is you need different shocks for the heavier springs, and they would suck on the street.

 

[bragging]I ran 200/250 with several different clubs and was always in the top 10% at track days including 12th overall out of 150 at a POC event (1st in the "not a Porsche" class) and 2nd overall at a local club event, and usually in the top 20% at autox including 2nd out of 200 at a NASA event.[/bragging]

 

Definitely not top of the field every time out, but certainly not mid pack as John would have you believe, although I think he hangs out with some faster drivers than I do. My car was definitely not a fast FP car, that's for sure. It's hard to be fast in a Prepared class with a 2350 lb Z that runs on pump gas. Instead of harping on how slow I was in my class, I just concentrated on the overall standings. One thing is true, I was always a bridesmaid and never a bride; never took FTD. 2nd twice but never fastest.

 

I did go the extra mile though and I hauled my slicks to the track and changed the tires right there. I also took the suspension farther than most with heims jointed front control arms and TC rods and camber plates.

[tube80z]

300# springs + 1" way bar is not enough.

 

 

 

Looking at the photo you can definitely see a lot of extension on the inside, which is pretty common. If you limit this you'll find that the car won't roll out of its geometry window as easily. I currently use 0 mm rebound on the front and 15 mm in the rear. If you run on rough courses you may need a little more but generally not more than 5 mm front and 25 mm rear. You don't really need a lot of rebound.

 

What you'll find is the car rolls less, turns in quicker, and puts the power down better. When I started doing this I started getting comments about how flat my car cornered. I found it was generally about 0.15 seconds faster on my standard referrence course. I also found the car more consistent and easier to drive.

 

Easy to do with cables and turnbuckles. Worst case you throw it all away and call it a waste of time. This is a common setup crutch that's not too well documented.

 

Cary

[gramercyjam]

300# springs are definitely not comfy on the street. Good tip Cary - I'll give it a shot after things slow down this summer. I still have a lot of suspension work to do to get things where they should be.

 

It's funny how one day, you find yourself outdriving a car you thought your driving skills couldn't keep up with in the first place.

[johnc]

BTW... with my comment above I didn't mean to imply driving the car on the street/ autox/track/drag strip wouldn't be fun. It would be a hoot! Even a box stock 240Z on a race track is an absolute blast. Its not the fastest way around the track but you'll be smiling and laughing the whole way.

[Montoya]

After reading through all the posts I am amazed nobody has said this before. If you stiffen the old Datsun chassis you don't need to run as stiff a spring. There are numerous ways to do this depending on budget and class rules; bolt in roll bar with strut tower braces, fully welded cage, seam welding the chassis, foam, or any combination. 300# springs on a tweaking chassis are probably about the same as 225# springs on a stiff chassis. Plus the stiff chassis is much more fun to drive being more communicative and responsive.