What CC are Pontiac 6X heads?
Pontiac Heads
| PONTIAC HEAD CHART | ||
|---|---|---|
| CASTING NUMBER | YEAR & FACTORY APPLICATION | CHAMBER VOL# CC’S |
| 6X | 75-79 350 & 400 ALL 75-76 455 | see chart below |
| 5C,5X,5G | 75-76 455, SOME 350 | 93-114+ |
| EDELBROCK | PERFORMER RPM ALUMINUM | 72 or 87 |
What degree are Pontiac heads?
Until ’67, the valves within in a stock Pontiac cylinder head were at an angle of 20 degrees from the piston centerline, and it was revised to 14 degrees after that.
What degree heads are LS heads?
The stock small-block angle is 23 degrees but as the angle approaches true vertical, the port flow improves. This is why the original production LS heads use a 15-degree valve angle.
What are 4X Pontiac heads?
The 4X head was the 49-state casting used on all ’73-74 400 and 455ci engines. Since Pontiac offered the 400 2-barrel, the 400 4-barrel with both manual and automatic transmissions, and the 455 4-barrel for 1973 and 1974, separate applications of the 4X head were required to meet such broad usage.
How do I know if my Pontiac engine is block?
On 1955–63 blocks, the casting code is on the passenger side of the block. For 1964–67, they are found on the distributor pad. Casting codes for 1968–81 appear on the ledge at the rear of the block behind cylinder eight. Once you locate the casting code, you can find your block through a number of searchable databases.
What is the bore and stroke of a Pontiac 400?
With a 4.12-inch bore and a 3.75-inch stroke, Pontiac’s 400 had similar bore and stroke to Chevy’s big-block 396 (even when the Chevy actually displaced 402 cubic inches).
Are all Pontiac blocks the same?
The blocks of all Pontiac V-8s from the 287 to the 455 are the same size and very close to the same weight, which can make it more difficult to identify the 11 different engine displacements produced from 1955–79. Adding to the confusion, multiple block codes were used, and date codes can overlap up to three decades.
How much horsepower can you get out of a Pontiac 400 engine?
Back in the day, the most powerful 400 (Ram Air IV) made by Pontiac put out 370 hp (GTO), so 512 hp is certainly a ton more performance; all in, it’s a package that looks deceptively stock.
What LS engine had 243 heads?
The 243 heads came on the LS6 engine produced from 2001 to 2006. It was typically found in the C5 Corvette, but it was eventually ported to the LQ4 and LQ9 to meet truck specs.