GTA LS Specific Updates & GCR Corrections
#33761 from Christopher DeShong · Rule change · TB 23-06 (2023-07 Fastrack)
In GTA Category Specifications, GCR Section 9.1.2.G., Appendix D, change as follows:
"1. Must meet all requirements listed in Appendix A.
2. An ECU re-flash to raise the maximum RPM limit to 6800 is allowed.2 3. The base LS-1 heads may be replaced with unmodified cylinder heads, part #243 or 799.
4. New intake valves, Manley #11360H, and exhaust valves, Manley #11361, may be installed to 243 and 799 heads to matchLS-6
specific 243 hollow intake & sodium exhaust valves.
5. New valve springs, isky #165A or GM part #12586484, should be installed to handle the higher RPM limit.
6. New ARP rod bolts, part #134-6006, should be installed to handle the higher RPM limit.
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7. Howard's Camshaft, PN #197715-10, may be used to unavailability of GM #12480110. 1.7:1 rockers must still be used.3. An ECU re-flash to raise the maximum RPM limit to 6800 is allowed.3. 8. Optional upgraded intake systems:
Option 1: Any 90mm throttle body may be installed. One example is GM part #12589181. A stock, unmodified LS-2 intakemanifold to fit the larger throttle body must be installed. A stock, unmodified LS-2 intake manifold, Gm part #12589181, must be
utilized.
Option 2: An LS-6 intake manifold (part #12573572 or #88894339) may be installed, but the stock 75mm throttle body must
remain in place.
Option 3: The fuel injection system may be completely removed and replace with a Holley 650 carburetor as specified in
Appendix B, item 16. This conversion also requires GM intake manifold part #88958675 and an MSD 6010, or MSD
6014CT, timing modules.4 9. The ASA-spec filter box and air meter ducting (bellows) may be replaced by aftermarket parts, but the stock Mass Airflow
(MAF) sensor must remain in place.5. New valve springs, Isky # 165A or GM part #12486484, should be installed to handle the higher RPM limit.6. New ARP rod bolt, part #134-6006, should be installed to handle the higher RPM limit.7 10. Competitors may upgrade their own ASA LS-1 engines, but ONLY the items listed in Appendix D, numbers 2
through 6 9 may be modified. NO other modifications are allowed.8 11. All LS-1 engines, Whether sealed or not, are subject to the same teardown policies as covered by the GCR."
In GTA Category Specifications, 9.1.2.G. GTA CATEGORY SPECIFICATIONS (REGIONAL ONLY), change as follows:
"9.1.2.G. GTA CATEGORY SPECIFICATIONS (REGIONAL ONLY and are not eligible to compete in SCCA Hoosier Super Tour events or
the SCCA Runoffs)"