NC Spring Perch Installation

Installations instructions for MonsterFlow intakes, Big Brake Kits, shocks and more.
Auto-x-er
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Re: NC Spring Perch Installation

Post by Auto-x-er »

I am using 2.5" springs with the Fatcat. I have not seen Brian's car, I am far away.

So is this what you are talking about then? http://www.good-win-racing.com/Mazda-Pe ... -0199.html

Getting expensive in parts to make this work.
skeeler
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Re: NC Spring Perch Installation

Post by skeeler »

Sorry; I got you confused with someone in Portland.

I think Goodwin's spring reducer is 2.5-2.25 inches; even though he doesn't say so in the description, he mentioned it in one of the forum threads. If your main and helper springs are both 65 mm, then you need something like this or the similar parts made by Hyperco or Eibach:

http://www.frsport.com/Swift-Stacked-Sp ... 4AodVWAA9Q

I don't think Goodwin sells a part like that.
2009, STR & DD. 1995, HPDE. 2004 MSM, sold. 2010 Mazda3, hers.
skeeler
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Re: NC Spring Perch Installation

Post by skeeler »

Brian,

As I mentioned, I've been using your upper spring perch adapters to run 70-mm straight springs in the rear of my NC. The 70-mm springs give me extra clearance to prevent rubbing the damper. In order to fit the 70-mm springs, I epoxied some carefully chosen hubcentric rings to the OD of the spring seat. Unfortunately, I still get a little rubbing between your adaptor and the damper.

So, would you be willing to offer a set of your adapters designed specifically for 70-mm springs, in other words machined with an OD of ~69.5 mm and and ID that's ~5 mm more than your current model?
2009, STR & DD. 1995, HPDE. 2004 MSM, sold. 2010 Mazda3, hers.
Brian
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Re: NC Spring Perch Installation

Post by Brian »

Did you space out the bottom connection per the directions in the production description? Properly installed there is no contact between spring and shock, no rub.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
skeeler
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Re: NC Spring Perch Installation

Post by skeeler »

Brian,

I didn't space out lower damper mount, since I didn't want to compromise the suspension geometry or the support of the lower damper by the upright.
2009, STR & DD. 1995, HPDE. 2004 MSM, sold. 2010 Mazda3, hers.
Brian
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Re: NC Spring Perch Installation

Post by Brian »

You are leaping to the assumption that the original arc geometry of the rear was in anyway ideal. To put it another way, you are also assuming that making that rear shock action more linear is somehow a bad thing. I humbly suggest there is no evidence to support those assumptions (the fact I am consistently TOP TIME OF DAY at event after event suggests we might even have improved that geometry, or at the very least not 'compromised' it).
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
skeeler
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Re: NC Spring Perch Installation

Post by skeeler »

Brian, you make a good point. Are you concerned about the bottom of the damper not being supported by the post on the upright? I guess it's never been a problem for you.
2009, STR & DD. 1995, HPDE. 2004 MSM, sold. 2010 Mazda3, hers.
Brian
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Re: NC Spring Perch Installation

Post by Brian »

Indeed never been an issue and I can't imagine many customers putting more stress on it than we do....with 18x10.5 wheels, 285/30/18 hoosiers and about 300 hp.

But if concerned on that point have a machine shop make you a little sleeve for better fit/support.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
RBNetEngr
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Re: NC Spring Perch Installation

Post by RBNetEngr »

I am using MeisterR CRDs. Is it advised to add the spacers and longer bolts to the rear bottom mounts on them, to move them more inboard?
Brian
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Re: NC Spring Perch Installation

Post by Brian »

RBNetEngr wrote:I am using MeisterR CRDs. Is it advised to add the spacers and longer bolts to the rear bottom mounts on them, to move them more inboard?
Not required but doesn't hurt.
Brian Goodwin
Good-Win Racing
www.good-win-racing.com
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