IRS vs Watts Link

[CYAZ06]

What is better for road racing?

[chicane23]

Is the Mustang IRS better than a properly setup up Mustang with a solid axle with a Watts link? Some IRS systems certainly are, but some aren't or have marginal advantages over a solid axle. The Mustang IRS system is a compromise for the Mustang chassis, as the Mustang needed to support both the solid axle and the IRS systems.
I have heard Ford Engineers say many of times that the Mustang IRS is a huge compromise and is not what the originally design was.

For the Corvette that was designed for an IRS has certain advantages and inherently performs better than a dual purpose chassis.
I have seen advantages of the IRS at Barber Motorsports Park, being able to use the whole track including the berms/curbing in turn 12. My GR40 car would not like crossing the inside berm. The IRS car in front of me for that particular corner would just track out normally and he was able stay on the throttle through that corner. With my car, the inside rear tire would run up on the berm and almost pole vault me to track out making me provide more steering input. This was quick solved by not using the berm.

I personally believe a rough track or huge change is surface heights from one rear wheel to the other seems to be a huge advantage with the IRS.

I think most knowledgeable drivers would be surprised at how well a Griggs Racing solid axle can perform. I know for a fact that I have had a very large number of Porsche, Vette, Viper, BMW guys that can’t believe they were just out run buy a Mustang much less one with a solid axle.

The biggest disadvantage is the IRS is heavy, expensive and not as durable, but I also believe it can be just as competitive if setup correctly.

Solid axle cost - $2051
TA - $449
Watts - $759
Control Arms - $189
Rear Coil-over kit with shocks and springs - $654


IRS - $3091 to $4589
MM IRS Grip box - $ 975
MM Coil over kit with springs - $429
Rear IRS Shocks - $308
KB Upper Control arms - $849 - optional
KB Lower control arms - $649 - optional
MM IRS Cooler - $1379
_________________
John G.
http://www.chicane23.com
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