How to build a Pontiac 400 engine for a 1968 Firebird?

We work with the Summit Racing tech department to help you tackle your auto-related conundrums. In this week’s Mailbag , we’re recommending a parts combo to get 400+ horsepower from a Pontiac 400 engine in a 1968 Firebird. Q: I want to build a Pontiac 400 engine for my 1968 Firebird.

When did the Pontiac 400 V8 come out?

Pontiac 400 V8 Engine. The Pontiac 400 6.6 Liter engine was first introduced in 1967. This version of the Pontiac V8 engine was used in the GTO, Firebird, and the Trans-Am Firebird. The 400 was inspired by the Pontiac 389 V8 and proved to be the last Pontiac engine with closed chambered heads.

What’s the firing order on a Pontiac Firebird?

IGNITION Like all PONTIAC engines since 1955, the firing order sets is: 1-8-4-3-6-5-7-2, all by turning it counterclockwise. Note that the cylinder number 1 is the next driver in front of the engine (the same location on all V-engines) or just the first behind the power steering pump.

Where is cylinder number 1 on a Pontiac Firebird?

Note that the cylinder number 1 is the next driver in front of the engine (the same location on all V-engines) or just the first behind the power steering pump. Oldsmobile V8 engines (260, 307, 350, 403 and 455ci) is identical to the pontiac: 1-8-4-3-6-5-7-2 counterclockwise.

What was the horsepower of a Pontiac Firebird in 1968?

For 1968, the same basic 400 remained, now rated at 330hp at 4,800 RPM and 430-lbs.ft. of torque at 3,300 RPM, and equipped with “16” cylinder heads; “62” heads were used on some automatic cars. Pontiac also added the L74 400 H.O. engine, using the “067” cam on automatics and the 288/302-duration “068” on manuals, both rated at 335hp.

When did Pontiac stop making the Firebird 400?

The 400 V-8 and the Firebird 400 package did continue into 1969, but the Firebird itself changed substantially enough that year to warrant its own separate consideration. So if you’re considering buying a 1967-1968 Firebird 400, here’s what you should look for.

What was the gear ratio on a 1967 Firebird 400?

DIFFERENTIAL The 1967 Firebird 400 could have come with any of the Firebird’s range of rear gear ratios in the B-O-P 10-bolt differential, from a 2.56 through a 3.90. Firebird 400 buyers who ordered a 3.90:1 gear ratio–which was required with the Ram Air version–could only get that ratio with a Saf-T-Track limited-slip differential.

Do you need to adjust rocker arms on a Pontiac?

Whether you have decided to stay with the stock type stamped rocker arms or Competition Cams Magnum Rollers Rockers as pictured here, or something far more exotic, you will need to adjust valve lash. Torquing the adjusting nut per the old Chilton’s to 20-25 ft pounds won’t work on any heads that have been milled.

Where is the block code on a Pontiac Firebird?

The date code for the Pontiac V-8s is found at the back of the block near the driver-side cylinder bank and distributor hole. The block casting number is found behind the passenger-side cylinder bank at the rear of the block. All engines installed in the Firebird have a block code. The block code tells you the engine and application.

How to build a Pontiac 400 engine for a 1968 Firebird?