We get TONS of questions on these items, which are Heeltoe's most popular coilover offerings. This video should answer 95% of your questions, and if any others come up be sure to ask below! Here are some timestamps for you:

0:37 Street Advance Z Details
3:11 Flex Z Details
5:00 Preload: What it is and how to adjust it.
6:30 Stroke/Travel Differences between SAZ and FZ.
10:28 Made in China or Japan, and why it doesn't matter.
12:00 Top hats reviewed; stock Base TL, stock SType bushings, and FZ upper mounts.
13:19 Why some upper mounts don't have camber adjustment and some do (shocks versus struts)
14:05 Heeltoe's exclusive Upper Mount Installation Services

SHOP Tein FLEX Z on Heeltoe: https://www.heeltoeauto.com/index.php...
SHOP Tein Street Advance Z (SAZ) on Heeltoe: https://www.heeltoeauto.com/index.php...
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