4 lug or 5 lug

how strong is the 4 lug axle? im trying to figure out if its worth it to do the 5 lug conversion. the car does see some track time but it is pretty much stock. i do plan on modifying it though. just wondering how much the 4 lug can handle
 
the lugs wont fail before the axle will. Stock or mostly stock and certainly on a street tire the lug configuration will not matter a bit.

Now throw some drag slicks, a shot of nitrous, and a 5000 rpm side step on the clutch, and that changes things.

I'll still bet the axle will go before the lugs shear off.
 
The switch from 4 lug to 5 lug isn't really about the strength.
You could always buy 31 spline 4 lug axles with cold hardened studs.

It's more about better wheel choice, 5 lugs is also visually more pleasing especially with 5 spoke rims, and by far it's easier to upgrade brakes.
 


Took the words outta my mouth