ARP B-Series Head Stud Kits for B16A, B18A/B, B18C, LS/VTEC

ARP Head Stud Kits for Honda B-Series: B16A, B18A/B, B18C, LS/VTEC - Part #208-4302 / #208-4303 / #208-4306 / #208-4601

Any B-series that's going to see boost, real compression, or a VTEC head on a non-VTEC block should have studs holding the head down, and this page has the four ARP kits that cover the family. Pick by the block and head combination, not by the car it's in: the B18A/B18B LS engines, the B18C1 GS-R and B18C5 Type R, the B16A2/B16A3, and the B20 or LS block wearing a B16 head each have their own part number.

What It Is and Why It Works

A head bolt twists in the block threads as you torque it, so some of what the wrench reads is thread friction, not clamp. A stud goes in hand tight and stretches on one axis when the nut is torqued, which gives an even, repeatable clamp across all ten positions and keeps an MLS gasket sealed when cylinder pressure climbs. ARP machines every kit here from 8740 chromoly heat treated to 190,000 psi, centerless grinds the studs straight, and rolls the threads after heat treat for fatigue strength. Each kit ships with 10 studs, 12-point nuts, hardened parallel ground washers, ARP assembly lube, and a torque card. The differences between the four are stud length and which positions get the shorter undercut studs, which is why the LS/VTEC and B20 VTEC kit exists at all: the B16 head sits on a taller block than it was designed for, and the studs have to reach.

Specs

Available Options

Fitment

The 208-4306 has no factory car because it's a hybrid kit; order it by the engine you built, not the chassis. Swapped cars follow the engine, so an EG with a B18C1 takes the 208-4303. The B17A1 in the 92-93 GS-R shares the B16A head architecture; ARP does not catalog it separately, so confirm stud length against your engine before ordering for one.

What to Know Before You Buy

The hybrid kit is where people go wrong. A B16 head on a B20 or LS block needs the 208-4306, not the B16A kit; the 208-4601 studs are cut for the shorter B16 block and won't give you full thread engagement on the taller one. Builders have run the 208-4303 on LS/VTEC and B20 VTEC combinations for years and it works, but the 4306 is what ARP catalogs for that job, and the price is the same. Whichever kit you buy, install the studs finger tight into a clean, chased block, put ARP's lube on the threads and under the nuts, and torque in three stages to the figure on the card in the box, not the Honda service manual number, which assumes oiled factory bolts. If the head is off for a gasket anyway, this is a twenty minute upgrade, and the next head gasket job goes faster because the head slides down over studs that are already aligned. Pair with a Cometic MLS gasket on anything boosted.