Here is Guy Chamberlain's Honda Civc Type R which uses a full 4130 full rollcage for HKS Drag Racing
This car is one of the fastest Type R's on the track today.
These cages are required for cars running from 9.99-8.50 seconds

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Paul Creswell's immaculate Type R Honda Civic which has recently left HRC with complete back-half rollcage.
Back half cages are required for cars running 11.99-9.99 seconds.
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