Nissan_Convert

I'm swapping out the stock springs on my B13 for GC coilovers over my koni red inserts. Does anyone know if its possible to gain an additional 1/2 to 1 inch of suspension travel by using longer springs to raise the vehicle accordingly? Is there any margin in the operational range of the strut with OEM springs? Would this damage the strut insert by overextending it during a shock rebound? presumably the control arms would angle slightly downward from horizontal. what handling changes would you predict with the new suspension settings? thank you -

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2002 SE-R Spec V
1992 SE-R

 

squirlz

I know Cusco and GC top pillow ball mounts will add travel in the front and motivational mounts in the rear will also add travel. I think it would be better not to raise the car as the center of gravity would also go up.
Read the suspension thread to learn more.

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It seems that some people have been spoon feed their whole lives, It is societies job to teach them how to use the spoon for themselves.

Nissan_Convert

Unfortunately the mounts aren't an option for me - otherwise would love to have them. True the center of gravity would raise with longer springs, but also the roll center would be slightly higher and therefore the roll couple would become shorter....so theoretically body roll would be reduced. However I've also read that an increase in jacking forces can occur. On the surface it sounds to me like a tradeoff...as reducing the body roll would help minimize camber changes under suspension loading that tend to badly affect McPherson strut-equipped cars. However would the increase in center of gravity and potential for jacking forces outweigh that impact?

suspension experts and those with experience and/or opinion please chime in.

98sr20ve

You need to talk rates with this conversation. Here is the basic principle. Your struts have a lot more shaft travel then the GC lowering springs in the 8 inch or less range. To get long travel out of GC springs you need a 10 inch spring and you need to lower the front perch. In the 325 range this is a HUGE benefit with shortened struts as you get OEM levels of travel and a lower ride height. But you need a lower perch up front. Otherwise just use a 8 inch spring. Find the COIL BIND height in the spring specs. Set the height so that the spring would ALMOST coil bind at full bottom (don't forget the bumpstop takes a little room). Key is to know the coil bind height of your spring.

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Steve

06 G35 6MT

Nissan_Convert

I'm thinking 300lb/in front and 250lb/in rear. A little higher suspension frequency in the rear than when stock. I'm hoping to keep the rear end pretty light for tight rallycross turns. I'm limited in the prepared class and so cannot relocate the front perch. Don't have the $ for shortened struts. Need the extra suspension travel due to the elevation changes on the course. With stock springs and koni specials I've been bottoming out left and right. I'm hoping the stiffer front end will minimize the outer wheel positive camber change when loaded in a turn. The rear end already rotated pretty well, but I'd like to try a bit more oversteer. maybe I don't need the extra suspension travel considering the springs will be so much stiffer ?

98sr20ve

All it cost is time and a little tools to shorten them yourself. I would go 325/275 8 inch in the front, 7 in the rear. It might need to be a 6 in the rear on a B13. I forget.