meek

Having taken out one seat, without any mangled bolts ( wooo-hooo! ), and having re-dyed it, I now need to put it back in. Does anyone know the torque value for the 6 mounting bolts? I have searched and now know the values for a GT3 and 996, but not the 964. Help

If no one knows the precise answer, how many grunts would be needed?

Lord_Galva

MisterRisky

I did two grunts with a 3/8 ratchet... 7" handle. If it gets tight and then starts to get loose again you should use 1/2 less grunt.

In all seriousness, torque on these is not mission critical. They should be tight enough to not allow the seat to wiggle but not so tight as to strip the threads. in the event of a wreck you just don't want the seat getting a 'running start' before it hits the tightness of the bolts. In my experience of taking my seats in/out twice, I think you are more likely to strip the hex heads before you over tighten them. Just get them nice and snug then come back in a couple days and recheck and you will be fine.

meek

Thanks Risky, Will do them in two stages and hope for the best. Will post some pics and a write up once it is all done; just the driver's seat to dye and it is finished...ish; there is always something to tinker with.

Rob in Oz

Do it up until it strips, then back off half a turn...

Rob

Stewart H

They should be as tight as a Scotsman's wallet

elbeee964

Meek-
I'm sorry I don't have an answer at hand for this. I truly wish I did, though.

Seriously, as a more general thread/group question: has anyone just gone to a better Grade of bolt and not reuse what sounds like an 'intended-for-factory-install-only-and-not-multiple-re-use' fastener? (ie, better known as, "IFFIOANMRU", or "Iffy-maru", for short. )

From everyone's stripped socket head horror stories, these sound like typical junk Grade 5's, or worse, materials. Plenty good, as Mr. Risky (!!!) points out for their intended end use, but a pain whenever you look to take them out.

Wouldn't a quick trip to any generic industrial "Bolts-R-Us" yield Grade 8's, or better, as worthy replacements?
That'd certainly make them worthy of at least a Three-grunt effort!

(I ask because seat replacement is my next task... Besides, if I knew the bolt parent material I could gin up a satisfactory min. torque based off the bolt material's Fty [tensile yield strength]. Just sayin'.)

Rocket Rob

I stripped two of my seat bolts and replaced them with a normal grade 8. The seat has been fine for 5 years but I've always wondered if it would cause a problems in a serious accident. I'm sure the factory had a reason for using the bolts that they did.

elbeee964

Rob- That grade 8 choice is as strong, at least, than factory. You're fine. Very few industries routinely use better than Grade 8's. Did they exhibit better resistance to installation abuse than your factory bolts? By that, I mean, did they take the hex drive more cleanly & w/o socket deformation? If so, your two are plainly stronger.

The factory's intents and ours intersect only on one point: that those bolts function satisfactorily when the time comes. (ie, the bolt isn't the first to break )
But there are many ways to "skin that cat".
And the way we might favor to answer that question may be uneconomic for the factory to entertain.
It wouldn't suprise me if the factory's selection were based on least cost, or some tamper-proof non-reusability liability worry, or "it's just not that much of a concern (if at all!) to the vast majority of its customer base".

I guaran-damn-tee you that the two(!) bolts holding onto my calipers are strong enough -- and how! -- and meant for, multiple re-uses. The factory's seat bolt selections are just made of less strong, but Perfectly satisfactory bolts for their first, intended use and installation.

Rocket Rob

The Grade 8 bolts threaded in very smoothly and without any socket damage. I'm always nervous torquing and loosening the factory seat bolts. The metal feels excessively soft and easy to strip the heads. I prefer the feel of the Grade 8 bolts. To be honest, on my new 964 coupe, I was removing the seats to do some work and stripped one. The only way I could get it out was to grind the head off with a die grinder. What should have been a simple 5 minute task, turned out to be a 1-2 hour job.

The first time, I mangled one of these bolts, I worried about the Grade 8 bolt heads being taller than the factory bolts and that they would interfere with the seat track movement. I was pleased to learn that the tracks slide smoothly, no interference.

Bottom line: I would have some spare bolts handy when your remove you seats, just in case you strip them. Good luck.

elbeee964

Rob-

Thanks for your experience(s) and the heads-up!
Will do.

-Lonnie

(Still... still wish I had an answer for Mr. meek. It's such a straightforward answer once you know the grade of bolt.)

meek

I will let you know if I manage to mangle them after the weekend. I have bought new ones anyhow, plus some spares. It is only the passenger seat at the moment, so if I do have a crash, it won't be me flying out of the windscreen

springer3

German torque spec: guten tite.

meek

ThomasC2

I have replaced all the seat bolts with black 12.9 spec allen bolts. Stronger and they are almost impossible to damage/strip if your´re not very carless.