View Full Version : Pressure Plate Bolts

08-17-2011, 05:52 PM
Hey Guys/Gals,
I'm trying to find the size for the pressure plate bolts on an 06 Evo, and I'm having difficulty finding anything but flywheels and pressure plates online, anyone have an idea where I can find the size (apparently my cousin thought it would be a good idea to keep bolts strewn about...)
Thanks for the help!

08-17-2011, 06:40 PM

08-17-2011, 07:16 PM


I once went into NAPA and created my own engine set using higher grades than what factory called for. It took me about an hour to pick them all out and match them, and it cost me about $20. Well worth the time. I did this for flywheel, pressure plate, motor mounts, transmission mount, transmission, intake and exhaust manifolds.

08-17-2011, 07:35 PM
Well that's what I plan on doing, going to one of the hardware stores and getting them in Grade 8, but I don't know the size (length/diameter/pitch)

08-18-2011, 07:08 AM
From memory they are M8x1.25, and the length is 15-20mm.

08-18-2011, 02:45 PM
From memory they are M8x1.25, and the length is 15-20mm.

Thank you much kind sir!

08-18-2011, 06:09 PM
There is no grade 8 in metric. Grade 8 is an american SAE bolt/nut term. In metric you want like a 10.9.

Hipster Lawrence
08-18-2011, 06:36 PM
I personally wouldn't do napa bolts just because they look like cheap hardware store bolts. Mcmaster Carr has any kind of bolt you want. In any material you want.

08-18-2011, 10:22 PM
To be honest, the pressure plate bolts don't need to be the STRONGEST there is. On the Evo, there are 6 bolts holding the pressure plate down. You don't have to worry about sheer forces as there are 3 pins that handle the sheer loads. Standard hardware would be fine to get. I personally would get stainless steel hardware just so you don't have to worry about corrosion, and make sure to use a lock washer and blue locktite on the bolts so they don't back out.

08-19-2011, 01:02 PM
IMO, it not always "best" to use grade 8 bolts or nuts.

Especially in the case of nuts that go on manifold studs. You want the nut to strip/break instead of the stud. For exhaust stuff when I re-do it I usually use brass nuts - strong enough to hold sufficient torque but soft enough to break off if they become frozen.

Certainly for something like a flywheel to the crank or engine to trans you want the strongest you can get. Same goes for head bolts but they are usually "special" and I would only use factory for them.

I'll go along with the recommendation of McMaster-Carr as well - I use them all the time for our metric hardware for the test system we make at work - they have like everything in any material and hardness you want - they usually have about 2 or 3 choices of stainless steel. NAPA is quality stuff - but with McMaster you really know what you are getting.