ARP Main Stud Kit for B18A1 B18B1 (Integra LS 90-01)

ARP Main Stud Kit for Acura Integra B18A1 B18B1 - Part #208-5404

The LS bottom end is the workhorse of the B-series world, and the moment you bolt a VTEC head on it and start chasing the 8,000 rpm the head can breathe at, the factory main bolts are the weakest thing holding the crank in. The ARP main stud kit for the B18A1 and B18B1 covers every 90-01 Integra RS, LS, GS, and Special Edition, and it belongs in every serious LS-VTEC plan.

What It Is and Why It Works

Main caps move under load, and cap walk chews bearings. Studs clamp the caps harder and more consistently than the stock bolts because the stud stretches on a single axis while the 12-point nut is torqued, so your torque wrench reading reflects true clamp load. The block threads also last longer since nothing rotates in them under load, which matters on a block that has been apart before or will be again. ARP machines the studs from 8740 chromoly heat treated to 200,000 psi with threads rolled after heat treat, and the kit includes 10 studs for the 2-bolt main B-series block, nuts, hardened parallel ground washers, and ARP assembly lubricant.

Specs

Fitment

Covers the non-VTEC 1.8L Integra bottom end, which is also the foundation of most LS-VTEC builds. The 86-89 Integra ran the D16A1 and does not use this kit.

What to Know Before You Buy

Plan the machine work. ARP notes an align hone of the main bores may be necessary after installing studs, because the higher clamp load can distort the bores compared to the factory bolts. Do this on a bare block with the caps torqued, verify bore size and alignment, then assemble. On an LS-VTEC or B20-VTEC build these go in alongside ARP 8mm rod bolts (208-6001) as the standard bottom end fastener package. Building a B20 block, several catalogs list this same kit for the B20B and B20Z since the bottom end shares the LS architecture, but confirm against your block before ordering. If the engine is staying a stock-rpm daily LS, the factory bolts are fine and your money is better spent elsewhere.