Widest Rear Tire?

The 456/456M wheel well easily accepted 355/25 19 Pirellis on 12.5" NF2s when those tires were available. Needed 25 mm spacers on the rear to prevent rubbing on the inside of the wheel well. You are probably more limited by wheel width for tire size unless you have huge HREs. Owners with NF2s now use 345/30 19 MPSS, but they need 11.5"-12.5" wheel widths.

Insufficient information to fully answer your question like wheel width and offset.

 

It really depends on the tire manufacturer, ie 325 width R888r is similar in width to other manufacturers' 345. If the 456 is anything like the 550/575, you can easily fit a 13" wheel back there. As far as 19" options, basically stay in line with what the GEN3+ Vipers are running on the back.

I've run 305 & 315 on the rear (11" HRE) and have plenty of sidewall and traction while still allowing some wheelspin to go easy on the driveline.

 

When choosing wheels and tires for your car, refer to the attached document...

 

Not to be an echo chamber, but we need to know how wide your HRE wheels are to provide an accurate answer. It also depends on the tire, as all tires have an minimum and maximum width wheel on which they can be safely mounted (and if varies slightly from tire to tire)

 

The widest you an go on an 11in wide is many, not all, 325 tires. Which tires are leaning toward? 325/30 19?

Pilot Sport 4S, Continental Extremecontact Sport, Goodyear F1, Bridgestone S007 all list 11in as minimum width and could theoretically fit.

 

I'm running 315/30 on an 11" and previously ran a 305/35 . There is a lot of meat for both of these tires.

305/35
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315/30
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