breale01

Any comments on whether using open end steel lug nuts is really necessary for Drivers Ed (Green Run Group, replica Cup I's)?

Buckeye

yes

KaiB

+964

breale01

OK, sold. Any source/brand in particular? The Rennline set seems good.

c didy

I think VW nuts work and can be easily obtained. The spherical seat is apparently the same. Do check with others though as this is something I have no direct experience with.

ThomasC2

+1. I bought my set from rennline. I think they are a "OEM" kit. a solid kit with a fair price. Just buy it.

FeralComprehension

FNG with and FNGQ:

Why open steel for DE?

Thanks!

ThomasC2

It's not that they are open. The steel nuts are more solid and the threads are stronger than on the stock alu.nuts.mon track everything gets very hot and the steel version keeps the wanted torgue better than alu which expands more.

Thomas

KaiB

Above +1 and the open nuts also allow the scruts to verify that enough stud thread is exposed.

FeralComprehension

Thank you for the cordial and detailed explanations.

breale01

+1

Rennlist....Ask a question....not only have it answered, but learn alot more

mongrelcat

Anyone have a photo handy? I'm curious about how they look (on the car.) Thanks.

Unkle

Just a question?
Not being into metalurgy, but how hot would you need to run to get the bolts to cause a potential risk on a track day? Doesn't the heat dissipate away from the hub through all metal contact surfaces (wheel, discs, hub, caliper, shock) and if you can touch a wheel it surely isn't hot enought to warp/expand alloy nuts excessively.

Or are the temps way lower for Alloy expansion than i am aware of?

race911

It's fine to use them, but I've never seen a stock lug fail even in competition. Ever. Since 1980. Lug nut requirement came into being because one too many dumb asses piled on spacers without regard to whether there was enough thread engagement. Then the above reference to easy tech inspection makes perfect sense. (I had one guy with an ex-factory race car try to pass my tech with stacked fender washers between the hub and wheel. Bitched to high heaven that some 21 y.o. dared send him home.)

So what do tech people do now on the cars with lug bolts??

Frank 993 C4S

To answer the OP's original question: For DE, your stock lug nuts are just fine provided you haven't added spacers that would limit your bolt thread engagement.

Be sure to tighten them with a torque wrench (to 130 Nm) after changing wheels and check them each morning during DE. If you want additional assurance, check them after lunch as well.

I have seen wheels come off cars several times. Usually happens on the first lap after the wheels had just been changed (and bolts not having been tightened).