89' Help bad shake above 45!

[90_240_Silvia]

When ever i hit 45 or above i get a horrible shake in my front end. I got the tires rotated and balanced and got my alignment done?

Any ideas?

I was thinking it might also be my tein full coilovers ? Also my friend said it might be because i took the power stearing out?

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I tightened the purches on my springs and it seemed to help!

[180fan]

how are the tension rod bushings?