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Old Mar 28, 2011 | 06:31 PM
  #41  
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Originally Posted by hustler
I'm about to put ~350/225 Hyperco springs on my daily w/ Ground Control perches, any thoughts on which free length for NA Bilstein HD's with NB upper mounts?
From my own setup with Bilsteins, FCM bottom perches, NB upper mounts, and Swift springs:

Front springs are 336 lbs/in (6 kg/mm) 8” long Swifts;
Rear springs are 224 lbs/in (4 kg/mm) 9” long Swifts;
Old Mar 28, 2011 | 06:58 PM
  #42  
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(zack morris's phone)

II had 8" 250# springs in the rear with 7" 400# front. Worked great for me
Old Mar 28, 2011 | 08:47 PM
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Originally Posted by JasonC SBB
Depends on the spring rate, car weight, desired ride height, and the difference between spring's free length, adn block length.

Basically you want the spring's installed length, *at full bump*, to be just a bit longer than the spring's block length.

Use FCM's spreadsheet.
That would take effort, someone's done it before...and it's my daily so I'm not exactly worried about it.

Originally Posted by Thucydides
From my own setup with Bilsteins, FCM bottom perches, NB upper mounts, and Swift springs:

Front springs are 336 lbs/in (6 kg/mm) 8” long Swifts;
Rear springs are 224 lbs/in (4 kg/mm) 9” long Swifts;
Thanks, how does it ride on the street? This is for my daily so I want it to not make me sick.
Old Mar 28, 2011 | 09:27 PM
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This was rec'd to me by Shaikh for 12.25" F / 12.5" R for my 1991.

Revalved NA R-pkg bilsteins, GC sleeve/perch, NB top hats

F: 6" 500lbs/in
R: 7" 325lbs/in

Will this have coil bind? Hopefully, I understood him correctly.
Old Mar 28, 2011 | 10:00 PM
  #45  
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Originally Posted by hustler
Thanks, how does it ride on the street? This is for my daily so I want it to not make me sick.
It rides surprisingly well, though not as well as my setup with the stock springs and Bernie's re-valved Bilsteins. Being twice the normal spring rate, though, that's to be expected.

I'd say it's perfectly livable, so long as exceptional comfort isn't one of your primary goals. It's compromised towards not bottoming the bump stops, and it's pretty good at doing that. I forgot to mention, and it's worth noting, that they're Shaikh's re-valves.
Old Mar 28, 2011 | 11:14 PM
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Originally Posted by Thucydides
It rides surprisingly well, though not as well as my setup with the stock springs and Bernie's re-valved Bilsteins. Being twice the normal spring rate, though, that's to be expected.

I'd say it's perfectly livable, so long as exceptional comfort isn't one of your primary goals. It's compromised towards not bottoming the bump stops, and it's pretty good at doing that. I forgot to mention, and it's worth noting, that they're Shaikh's re-valves.
I'd leave mine as is, but the damn tires are always rubbing the fenders and I'd like to auto-x this car. The perfect balance on this car was when I had MSM springs on it, although it was skyjacked. Any thoughts on what those MSM rates are?
Old Mar 28, 2011 | 11:32 PM
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Originally Posted by hustler
I'd leave mine as is, but the damn tires are always rubbing the fenders and I'd like to auto-x this car. The perfect balance on this car was when I had MSM springs on it, although it was skyjacked. Any thoughts on what those MSM rates are?
According to Shaikh's spreadsheet they're 215/158. That's probably a near perfect compromise between fast road work and comfort, at some reasonable ride height of course. But they might be a tad soft for autox, where I think the 350/225 rates probably have an advantage. On the other hand, a friend of mine does quite well autox-ing his 94R with stock rates. Another thought is that perhaps you could also go with longer bump stops (58mm) which effectively gives you a more rapidly increasing progressive spring rate.

While you're mulling over the 350/225 Hypercoils, you might give a thought to their 8x225 / 10x150 springs. They're effectively the same rates as the MSM springs you found worked so well, but might work with your GC/NB setup as well.

Last edited by Thucydides; Mar 28, 2011 at 11:54 PM.
Old Mar 28, 2011 | 11:36 PM
  #48  
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Originally Posted by kenzo42
This was rec'd to me by Shaikh for 12.25" F / 12.5" R for my 1991.

Revalved NA R-pkg bilsteins, GC sleeve/perch, NB top hats

F: 6" 500lbs/in
R: 7" 325lbs/in

Will this have coil bind? Hopefully, I understood him correctly.
Shaikh wouldn't recommend a setup susceptible to coil bind. Hopefully you understood him correctly.
Old Mar 29, 2011 | 09:12 AM
  #49  
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Im a little more confused on what i want now. I was thinking maybe
Koni sport front 6" spring 450 rate with koni sleeve/perch nb top hat
koni sport rear 7" spring 350 rate with koni sleeve/perch nb top hat
Big sway bar in front.
I want something capable of going low enough, but with a decent ride quality and handleing. Im not looking for the best, just a set-up that will get the job done for what i want it to do. Its a second car that will mostly get street driven as i live in the country with nice driving roads around.
Old Mar 29, 2011 | 09:13 AM
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Oh also wheres the cheaspest place to buy the nb top hat conversion at? Is there some spec miata sites that sell it for cheap.
Old Mar 29, 2011 | 09:18 AM
  #51  
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Those rates are pretty close to what I have and they ride well with my revalved Bilsteins. The cheapest place to get NB tophats is used or from Mazda Motorsports (which you need to register for and submit racing/autocross results for, but it is totally worth it.).
Old Mar 29, 2011 | 10:04 AM
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Originally Posted by 89325iturbo
Oh also wheres the cheaspest place to buy the nb top hat conversion at? Is there some spec miata sites that sell it for cheap.
First off, buy NB shocks. then get the OEM NB mounts for cheap from a dealership.

Old Mar 29, 2011 | 10:15 AM
  #53  
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And your ride height will go up an inch and a half. Otherwise, yeah, that's the solution.

Wait, are you suggesting that route with adjustable bottom perches? Actually, that should work and there's no worries about NB top mount fittings cobbled to work with NA shocks. Also, NB shocks are valved pretty good from the factory, unlike their NA cousins which are **** out of the box. Good idea.
Old Mar 29, 2011 | 12:11 PM
  #54  
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So nb shocks and top hats, with adjustable coilover sleeves will still be able to go as low na shocks with nb top hats? If they're an 1-1/2 longer how does that work? Wouldnt the shock just be compressed an inch and half more? i thought you would want shorter shocks to be able to go lower.
Old Mar 29, 2011 | 01:04 PM
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You have to knock the tabs off the NB shocks to get the sleeves to sit on the circlip.
Old Mar 29, 2011 | 02:06 PM
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Originally Posted by Thucydides
And your ride height will go up an inch and a half. Otherwise, yeah, that's the solution.

Wait, are you suggesting that route with adjustable bottom perches? Actually, that should work and there's no worries about NB top mount fittings cobbled to work with NA shocks. Also, NB shocks are valved pretty good from the factory, unlike their NA cousins which are **** out of the box. Good idea.
what's this about an inch and a half? NB shocks with NB mounts swap directly over to an NA...
Old Mar 29, 2011 | 02:09 PM
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I think the ride height issue is only when swapping NA running gear for stock NB gear due to the different spring lengths.
Old Mar 29, 2011 | 05:02 PM
  #58  
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Originally Posted by Adam777
I think the ride height issue is only when swapping NA running gear for stock NB gear due to the different spring lengths.
That's the issue, and that's why Hustler said his MSM setup was skyjacked.

I believe the shocks are also a bit longer, but the majority of the increase in ride height when swapping out NA parts for NB parts on an NA car is mostly a function of spring length and the position of the lower perch on the shock. If you're using aftermarket springs and adjustable lower perches you can probably work around that problem reasonably easily.
Old Jun 24, 2011 | 08:47 PM
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Anything to worry about here?

92
Car sits at 11.5/11.75

Sending my extra set of Koni yellows to be revalved
NB top hats
Probably going to end up with ground control sleeves

Thinking
700 F 5"
450 R 6"
Old Jun 24, 2011 | 10:06 PM
  #60  
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6'' front 7'' rear. a



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