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Posted by: Mueller Oct 30 2003, 05:55 PM

With the new vented /4 front hub coming out soon (prototype next week I hope), proper torque of the wheel bolts will be critical as in not too tight.
(factory specs okay)

There is a safety factor built in of course, but if you don't use a torque wrench and have the strength of a gorilla, "something" is going to give

Posted by: ChrisReale Oct 30 2003, 05:56 PM

I aklways torque to 94 lbs. The one time I didn't, my wheel fell off while I was driving. Lucky fir me I was only going 15mph at the time

Posted by: Part Pricer Oct 30 2003, 06:01 PM

I torque my nuts at least once a week...wait, that didn't sound right.

I check the torque of the lug bolts on my car at least once a week. Ah, better. If I'm going to an AX, I will check the torque before I leave the house, check the torque before I run, and check the torque again after the event before I head home...and I mean the lug bolts.

Posted by: Air_Cooled_Nut Oct 30 2003, 06:09 PM

I torque lugs/nuts to spec then after 50-100 miles I check them to make sure then that's it until they come off again.

Posted by: Bruce Allert Oct 30 2003, 06:38 PM

Yup. Just before AX & everytime I take a wheel off to do sumpin. I been torquing to 95#
bruce

Posted by: SirAndy Oct 30 2003, 07:47 PM

100 lbs all around ...

Andy

Posted by: davep Oct 30 2003, 07:58 PM

Yes, in three steps 60, 80, 95.
When I worked in a VW+Audi dealer we had tires changed at local shops. They used the air gun to put the wheels back on and would warp the rotors. That was far too expensive. Did I ever ream them out for the practice. And do not lube the bolts/nuts. That can cause you to over-torque a fastener. It is not a trivial exercise despite appearances. I'm forever having to remind the production team on why the rules have to be followed.

DaveP

Posted by: Aaron Cox Oct 30 2003, 08:35 PM

I aklways torque to 94 lbs. The one time I didn't, my wheel fell off while I was driving. Lucky fir me I was only going 15mph at the time

Posted by: Curvie Roadlover Oct 31 2003, 05:08 AM

Little bit of anti-seize and 95 lbs

Posted by: James Adams Oct 31 2003, 08:01 AM

Mike, you are asking this for the screw-in version of the hubs, right?

IMHO I believe you should only offer pressed-in type studs with alumunim hubs. There is just too much risk of screwing the threads up over the many times they will be on and off.

If someone already has the long bolts for factory alloys, I think they could sell those and make up a good portion of the money to buy 911 studs and nuts anyway.

Posted by: davep Oct 31 2003, 08:32 AM

For a design such as this, studs and nuts would be much preferred. New nuts are cheaper than a new hub.

DaveP

Posted by: fiid Oct 31 2003, 09:54 AM

I agree - I much prefer to play with nuts. Errr..... I mean - it's nice to be able to drop the wheel on the studs while you fuble around trying to get the lugs on - it's hard work holding the wheel up while you get that first lug in with the stock system.

Fiid.

Posted by: silver six Oct 31 2003, 03:46 PM

If I'm not mistaken it's 94 lb/ft for five lug and 108 lb/ft for four lug. Word to your mother.

Douglas

Posted by: Part Pricer Oct 31 2003, 03:55 PM

Correct me if you're wrong, but I believe the following to be true:

It is 96 lb/ft for alloys (Fuchs 4 or 5 bolt, Pedrinis, Mahles) and 104 lb/ft for steel wheels.

Posted by: Curvie Roadlover Oct 31 2003, 03:59 PM

Posted by: markb Oct 31 2003, 04:07 PM

We generally do 85 lbs for alloys at the shop. Is that too little?

Posted by: Part Pricer Oct 31 2003, 04:18 PM

OK. You just made me dig out my VW/Porsche 914 Repair Guide, a Glovebox series book by Peter R.D. Russek., published by Peter Russek Publications Ltd.

According to this comprehensive technical manual:

Standard (steel): 15 kgm (108 lb. ft.)
Light Alloy : 13 kgm (94 lb. ft.)


Based on this, I would say that 85 lb. ft. is well below spec.

Posted by: silver six Oct 31 2003, 04:19 PM

Posted by: Part Pricer Oct 31 2003, 04:36 PM

I see the source of the confusion. You are using an older version of the manual.

If you look at the version published in 1974, you will see that Porsche specified:

For 25mm bolts (for steel wheels): 108.5 Lb. ft.
For 39mm bolts (for alloy wheels): 94 lb. ft.
For nuts: 94 lb ft.

So, we both are right. Wanna grab a beer?


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Posted by: roundboy914 Oct 31 2003, 06:11 PM

94 lb/ft, and do NOT forget the anti sieze.

Posted by: aufaber Oct 31 2003, 06:22 PM

Posted by: Rob Ways Oct 31 2003, 07:07 PM

I take my wheels off and on about 30-35 times a year with a 1/4 in spacer. Studs would be a real benefit. You lose the stock look though.