with my 75 im using an extreme flywheel made by Adelaide clutch now the original flywheel bolts seam a little too short, they stick out through the flywheel at 7mm. i went and brought some 8.8 grade high tensile bolts and one of them snapped off in the crank (was up to 90nm on the torque wrench and manual says 132nm) i was able to extract it easily enough. here is a pic of what i mean with the factory bolt

http://i148.photobucket.com/albums/s10/bigperry/TJ%20Sports/6g75/null_zpsa1e55c1d.jpg (http://s148.photobucket.com/user/bigperry/media/TJ%20Sports/6g75/null_zpsa1e55c1d.jpg.html)

do you guys think the factory bolts will be ok or am i just be fanatic about them

Measure the thickness of the flywheel at the bolt holes for both flywheels, whatever the difference is, needs to be taken up by new bolts.
You basically want the same protrusion as on the standard setup.
And 8.8 bolts shouldn't let go like that.

Ummm yes they should, there is no way in hell a 8.8 tensile bolt that diameter would take that torque

Perry you need to get some of matching tensile, flywheels do a lot of damage when they let go

Ok what tensile should I ask for , 10.9?

I will try and remember to look at some original ones tomorrow mate, need to match what Oem ones are

I will try and remember to look at some original ones tomorrow mate, need to match what Oem ones are

Ok cool, I went and brought some new oem ones which are the same between the 74 and the 75. There's no markings on them

My manual says 98 Nm for the flywheel bolts.

ARP after market bolts have a tensile strength of 12.9, about 50% stronger than 8.8 bolts.

My manual says 98 Nm for the flywheel bolts.

hmm is that the magna one or the 380 one, i was going off the 380 manual

Just an FYI, I've always used the following link as a rough guide to work out safe torque on high tensile bolts. This does not take all the variables into account but gives you an idea.

http://electronicfilters.tpub.com/TM-10-4330-237-13P/css/TM-10-4330-237-13P_105.htm

Always use the specified torque if there is one as it will apply the correct clamping force.

hmm is that the magna one or the 380 one, i was going off the 380 manual

Magna manual says 98Nm, 380 manual says 132Nm.

i recently got heavy duty flywheel which my mates from RPW didnt tell me i needed longer bolts or supply them.....there hard as **** to find...i think you need 20mm lenth 1mm pitch from memory mate....good luck finding them but, dont think arp do them and fasners 8.8 will make them but as mal said no where near strong enough... should go air craft quality 12.9 i think it is !