Description:

what? why would anyone buy new thru bolts?  go to my website and read the section "Tension Bolt Tech." (http://www.colemanprecisionrotaries....bolt-tech.html)
you will find that i tested all the tension bolt/thru bolt options and no surprise Mazda tested at 150,000 psi! that is metric 10.9 territory/Grade 8 in the USA. not far behind aftermarket options.

BUT, there is a BUT.

if your motor was rebuilt previously and you weren't looking over the guy with the torque wrenches shoulder it would be a good bet he cranked on the wrench more than the 28 ft pounds.. hey, more hp, more torque on the thru bolts. guess what happens when you over torque a bolt...it stretches into "yield" land. and becomes linguini. take a thru bolt and mike it... it should be 9.35 mm. you will find yours are less. that's because the bolt was stretched into yield.

simple: if your motor was previously rebuilt you would do well to toss the thru bolts.

a new set is $500 for the thru bolts and $40 for the washers.

i offer them to you from my brand new (not run) motor for...   $350 shipped with a set of $40 Mazda washers.