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mountune Sport Spring Review

BRGT350

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MKVIIST

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#4
Great video as always.[thumb]
 


OP
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BRGT350

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Thread Starter #5
Here are the measurements before and after the spring installation

Before:
Front 24.75" with -1.0' camber
Rear 24.88" with -0.4' camber

After installation a drive around the block
Front 24.63" with -1.2' camber
Rear 24.63 with -0.4' camber

After a week
Front 24.25" with -1.4' camber
Rear 24.25" with -0.4' camber

After a month
Front 24.00" (forgot to measure camber)
Rear 24.13" (forgot to measure camber)

Front delta: .75" lowering
Rear delta: .75" lowering

It is interesting how the height stayed the same front and rear for awhile, and then the front settled to be an 1/8 of an inch lower than the rear.

Here are a few pictures of the car a month after installation;

2015 Ford Fiesta ST Martini Racing 093 by Bryan Redeker, on Flickr



2015 Ford Fiesta ST Martini Racing 060 by Bryan Redeker, on Flickr
 


MOFiST

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#6
Thanks for sharing that info and looking forward to the how to.
Did you use a professional gauge to measure/set camber? Did you align it yourself?
 


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BRGT350

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Thread Starter #8
Thanks for sharing that info and looking forward to the how to.
Did you use a professional gauge to measure/set camber? Did you align it yourself?
I have a professional camber gauge and use strings to measure toe. I had trouble getting the jam nut loose on the tie rod when I went to align the front toe, so I took it to a shop to have it done. Their numbers for camber matched what I saw with my gauge. I needed about an 1/8 of a turn on the tie rod to bring back into spec.
 


Hijinx

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#10
I have 205/45-17, which may be two tall for the rear. Are you close to rubbing the fender liners anywhere? Would you happen to know their spring rate?

Edit- if that information is in the video forgive me. I haven't had an opportunity to watch it.
 


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BRGT350

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Thread Starter #11
I have 205/45-17, which may be two tall for the rear. Are you close to rubbing the fender liners anywhere? Would you happen to know their spring rate?

Edit- if that information is in the video forgive me. I haven't had an opportunity to watch it.
mountune lists the spring rate as 5% stiffer than stock and I think the actual rate is published in one of the stickies somewhere. As for rubbing, nothing at all with the wider and taller than stock tires. I have a good amount of clearance around the tire and the inner fenders. I haven't checked the front at full lock and full jounce since that isn't easy. I will try and get some numbers on how much clearance there is around the tires and fender liners.
 


YIN

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#12
mountune lists the spring rate as 5% stiffer than stock and I think the actual rate is published in one of the stickies somewhere. As for rubbing, nothing at all with the wider and taller than stock tires. I have a good amount of clearance around the tire and the inner fenders. I haven't checked the front at full lock and full jounce since that isn't easy. I will try and get some numbers on how much clearance there is around the tires and fender liners.
How about the offset of rim ?
I plan to use M spring and 215/40/17 with 17X7J ,offset 42. will it rub ?
Thx
 


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#13
mountune lists the spring rate as 5% stiffer than stock and I think the actual rate is published in one of the stickies somewhere. As for rubbing, nothing at all with the wider and taller than stock tires. I have a good amount of clearance around the tire and the inner fenders. I haven't checked the front at full lock and full jounce since that isn't easy. I will try and get some numbers on how much clearance there is around the tires and fender liners.
Hey BRGT350,

Are these springs OK on the stock shocks? Mountune says they are, but they're a business in it for profits of course.

Thank you in advance!

- JR
 


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BRGT350

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Thread Starter #14
these springs are prefect with the stock dampers! I have installed countless number of aftermarket springs on all sorts of cars with stock and aftermarket dampers. None of the aftermarket springs with stock dampers performed correctly and needed better dampers. Not the case with the Mountune springs. They are matched for the factory dampers and really toned down the over damped rear suspension. The Mountune springs are one of the best upgrades for the money.
 


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#15
They are matched for the factory dampers and really toned down the over damped rear suspension.
How so? I would assume that a lower ride height and stiffer springs would make the ride even more harsh if anything, but I am far from an expert when it comes to suspension tuning. I could certainly see some performance benefit to this setup of course. Maybe you just mean they are a better match for the dampers than the stock springs?
 


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BRGT350

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Thread Starter #16
controlling the spring rate is a function of the damper rates. My Mustang, for example, has a wheel rate (that is the spring rate at the wheel) is roughly 4 times what it was from the factory. This should be horribly harsh, but once the spring rate was matched to a proper damper rate, the ride is firm and not harsh. The dampers are matched to handle the spring rate. The same with the Mountune springs, they take advantage of the high damper rates of the factory springs to create a very well balanced setup. I would say the 5% increase in spring rate is the most you would want to go with the factory dampers. Anymore than that and you would overcome the damper rates and the ride would be harsh. You could still up the damper rates with the Mountune springs and come up with even better performance, but from just the springs, the handling and ride quality is very nice. Another thing about the Mountune springs and factory dampers, the springs don't lower the ride height enough to worry about bottoming out the dampers at full bump travel. I have seen lowering springs in the past that blow out the shocks and struts due to there not being enough travel.
 




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