Topic: Z suspension
Hi i need some help setting up our z with suspension. I see other z's taking cornors and holding speed where we have so much body roll we can not carry any speed any help would be great thanks
#28 Frak This Racing green z
- Jeff G 78
- Lemons Staff Stalker
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Re: Z suspension
Yeah, I've watched videos with your Z in them and it looks pretty terrible in the corners. I'll email you a few ideas. I'm sure Troy will chime in too.
BRE Datsun (Broke Racing Effluence) formerly Dawn of the Zed Racing
'74 260Z
Facebook page http://www.facebook.com/editpicture.php … 2559430584
'74 260Z
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- Troy
- Lemons Staff Stalker
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Re: Z suspension
I sent you guys a email.
I found a lot of cool parts online a locally.
Primarily, get the car lower, stiffen it up and add camber.
Troy
#35 LRE
1973 Datsun 240Z
#35 LRE
1973 Datsun 240Z
Re: Z suspension
We could use some help too! (240z). We've got the camber figured out with some offset aluminum bushings for the control arms, but need stiffer springs +/- a lower stance.
We had the idea of putting some e-bay coilover sleeves and springs on the stock strut housings, but the OD of the housings is 1/16" too large for the ID of the coilover sleeves.
Any advice?
- Jeff G 78
- Lemons Staff Stalker
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Re: Z suspension
fifty, email me at jeffgrauer at yahoo dot com. I'll forward the note I sent to Heathc182.
BRE Datsun (Broke Racing Effluence) formerly Dawn of the Zed Racing
'74 260Z
Facebook page http://www.facebook.com/editpicture.php … 2559430584
'74 260Z
Facebook page http://www.facebook.com/editpicture.php … 2559430584
Re: Z suspension
What you want is really stiff springs. You can calculate the new spring rate and ride height using the formula for a coil spring (search the web, there are plenty of car guys doing this). plug in the numbers (free length, turns) for a spring and calculate the spring rate, then calculate the car's ride height with that new spring rate. do some math before hand to know where you are starting from and then what your "new" springs will be.
You can increase the stiffness of your stock springs by cutting them, but that probably won't be stiff enough. So take the diameter numbers and your calculator to the JY and start looking under 3500-5000 cars (also see if you can find the little Mitsubishi truck, or Dodge D50 mini truck, they have really stiff front springs which are about the right size to match Datsun struts). Find some right diameter springs and calculate the spring rate, then use your cars weight per corner to find a new ride height. Then calculate how much you want to cut off and recalculate the spring rate, and then plug that back into the ride height calc.
Kind of tedious, an excell spreadsheet helps a lot, but you should be able to find JY springs that will make your car work.
Dudes Ex Machina: https://www.facebook.com/dudesexmachina
?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche
?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche
- Troy
- Lemons Staff Stalker
- Offline
Re: Z suspension
The 240Z has smaller diameter strut housings than the 260 and 280. At least in the front. I don't recall the diameters off the top of my head.
We used some cheap coil over stuff marked Saturn a friend had laying around. The threaded parts were too long so we cut them down.
Measure your housings then look at kits on eBay. See what's cheap and common. Then go to the junk yard or try to find the housing diameters some where and see what you can use.
Troy
#35 LRE
1973 Datsun 240Z
#35 LRE
1973 Datsun 240Z
- russian
- Effluent
- Offline
Re: Z suspension
mackwagon wrote:
What you want is really stiff springs. You can calculate the new spring rate and ride height using the formula for a coil spring (search the web, there are plenty of car guys doing this). plug in the numbers (free length, turns) for a spring and calculate the spring rate, then calculate the car's ride height with that new spring rate. do some math before hand to know where you are starting from and then what your "new" springs will be.
You can increase the stiffness of your stock springs by cutting them, but that probably won't be stiff enough. So take the diameter numbers and your calculator to the JY and start looking under 3500-5000 cars (also see if you can find the little Mitsubishi truck, or Dodge D50 mini truck, they have really stiff front springs which are about the right size to match Datsun struts). Find some right diameter springs and calculate the spring rate, then use your cars weight per corner to find a new ride height. Then calculate how much you want to cut off and recalculate the spring rate, and then plug that back into the ride height calc.
Kind of tedious, an excell spreadsheet helps a lot, but you should be able to find JY springs that will make your car work.
but when you are in a YJ, how do you know free length? or do you mean doing your homework at home finding the matching springs and then hunting for them?
ford escort front: # Spring size: Inside Diameter 5.65', Bar Diameter .593', Installed Height 7' # Load rating: 690 lbs. # One tangential and one pigtail end - how do I find vehicles with matching spring diameter? any web site with sizes database?
Re: Z suspension
Russian,
Well first if you can do some home work at home.
1. try and estimate the weights on the front and rear of your car from stock, then from your Lemons cut down/gutted out weight.
2. Then decide if your going to try adn get to equal or different rates front and rear. The easist to design to is equal front and rear, but its all a crap shoot in JY diving.
3. Check the forums for your car and see if anyone has info about springs from other cars that fit your stock struts/mounts.
4. Then you'll just have to go to the JY and measure some springs. Yeah this is time consuming, but its cheap.
As far as free length, most cars in the JY are up on supports with the suspension hanging in the air. Now not all of the springs are completely free (unloaded), but you can just assume that and make a couple guesses. The big thing is finding the matching diameter to your mounts, if you can find a couple, note that manufacturer and see if they have other vehicles with the same sized spring, but maybe in a different rate. then with your calculator you can run a couple rate calcs and see if its what you want. Remember you run an initial calc to find out the initial rate, then you'll need to figure out what you should cut that spring to to get the ride height and then what its new rate will be.
Dudes Ex Machina: https://www.facebook.com/dudesexmachina
?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche
?Everyone who has ever built anywhere a 'new heaven' first found the power thereto in his own hell- Frederick Nietzsche