Engine block deck height is the distance from the centerline of the main bearing bore to the flat surface of the block where the heads bolt on.
How is it measured?
The easiest and most accurate method is to have it measured by a machine shop.
To measure it yourself, use a pair of 12 in. Calipers and a Dial Bore Gauge. Be sure to measure all the cylinders. The height will vary slightly between the cylinders.
- Install main caps without bearings.
- Measure the main bearing bore.
- Divide the bore measurement by 2 to find the radius.
- Hook the jaw of the caliper on the main bearing bore.
- Measure up through the cylinder to the deck surface.
- Add the bore radius to the caliper measurement.
How does it affect performance?
Engine block deck height will play a role in selecting:
The deck height will be reduced if the block is "decked" by a machine shop. This will affect Deck Clearance and Quench.