Thread: 3.9 Cylinder Head Bolts

Torques are specified by ARP. You NEED to follow their proceedures. With sacrificial gasket for first torque sequencing, tension in factory sequence in 3 equal progressive torques to max, 5 times to pre stretch studs, measure before and after stretch sequence.Check for any over spec.

Yes you can fit the head over the studs save for leaving the rear most studs out and fit them after fitting head. It's been noted on here previously and where I first realised it, as I refitted my heads with the engine out of car.

I've used ARP's on anything from stock Renaults to 1000hp+ Toyo 6's & V8's (one at over 50psi boost) and never had a head or gasket or stud failure.

When I swapped to a 4.6 in my disco I did a test on a new set of TTY bols and the variation in release tension and stretch was scary. As little as 38lb retained tension and stretch length variation as well as stretch location variation.

Originally Posted by PhilipA

Maybe it is just a missprint ( 6 instead of 8) as the 215 was the CID of the 3.5 V8 and it was known as the BOP215..

Maybe there are 215V6s also .
However if you google Buick 215 V6 everything comes up as V8, and an historical footnote is that the Buick V6 produced from 3/4 of the V8 AFAIK became the Holden 3.8.
Regards Philip A

The V6 was first produced in 1962 at 198 cubic inches. In later years it was produced in 225, 231, 252, 196, 181, 270 cubic inches, and 270 ci turbocharged in the Grand National front wheel drive rocketship in the 90's.

For some years four different displacements were in production simultaneously and up to 6200 per day were made. It came in front and rear wheel drive versions, carburetted and fuel injected, distributor and distributorless ignition, naturally aspirated and turbocharged, manual and auto transmissions.

By using a variety of production and/or after market components, the engine can be built in 151, 209, 244, 265, 272 cubic inch versions.