[HWYSTR455]

Not sure about 4", but know 3.5 is no problem, and would imagine 4 would also have clearance.

There are many factors for driveshaft design, too much to go into here. You can brush up on it by hitting vendor's website, most have good tech articles on it.

Here's a very basic one from MotorTrend:

https://www.motortrend.com/how-to/cc...alancing-tips/

Stated there, factory driveshafts are only balanced to 3000-3500 RPM. "They are rated for no more than 350ftlbs or 350-400hp".

Same article on 1310/1330 joints: " The smaller size basically becomes a fuse, and it will eventually fail."

That's pretty much for optimum setups, if your driveline angles are off, it happens sooner.

Then there's critical speed, the point the shaft turns to spaghetti. Smaller diameter tube, longer the driveshaft, heavier the driveshaft is, and heavier the car, start subtracting.

What's the saying around here? "You can fall off a log and make 500ftlbs/500hp."

Can't believe how many overlook such an important part of the driveline. $350-$500 is just not worth the risk, period.

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