aluminum flywheel and bolts - ZR-1 Net Registry Forums

ZR1 MK · 02-28-2006

He are some pictures to show and clarify the Fidanza flywheel and mounting bolts. I used 1 1/4" grade 8 flywheel to crank bolts and zr1products.com (Specialized Racing Products) pressure plate to flywheel bolts (ARP 200,00 psi). The stock flywheel to crank bolts are too long to use in the aluminum flywheel and the stock pressure plate to flywheel bolts are too short for the aluminum flywheel.
Keep in mind, all grade 8 bolts are not created equal. There are lower quality grade 8 bolts, probably from China, that are equal to USA made grade 5 bolts. Know your sources.
The Grade 8 flywheel to crank bolts I used are fine for typical usage. High power cars and extreme usage can benefit by using ARP 230-7303 bolts. ARP doent classify there bolts into grades, but rather psi rating. A grade 8 bolt is in the 150,000 psi range, where by, the ARP 230-7303 is a 200,000 psi bolt. Its considerably stronger. I will be using the ARP 230-7303 bolts when I get my higher power engine installed later in the year.

02-28-2006	#1
ZR1 MK Join Date: Aug 2005 Location: NY Posts: 142	aluminum flywheel and bolts He are some pictures to show and clarify the Fidanza flywheel and mounting bolts. I used 1 1/4" grade 8 flywheel to crank bolts and zr1products.com (Specialized Racing Products) pressure plate to flywheel bolts (ARP 200,00 psi). The stock flywheel to crank bolts are too long to use in the aluminum flywheel and the stock pressure plate to flywheel bolts are too short for the aluminum flywheel. Keep in mind, all grade 8 bolts are not created equal. There are lower quality grade 8 bolts, probably from China, that are equal to USA made grade 5 bolts. Know your sources. The Grade 8 flywheel to crank bolts I used are fine for typical usage. High power cars and extreme usage can benefit by using ARP 230-7303 bolts. ARP doent classify there bolts into grades, but rather psi rating. A grade 8 bolt is in the 150,000 psi range, where by, the ARP 230-7303 is a 200,000 psi bolt. Its considerably stronger. I will be using the ARP 230-7303 bolts when I get my higher power engine installed later in the year. Last edited by ZR1 MK; 03-07-2006 at 01:33 PM.