Honda B DOHC Piston Measurements
We have obtained multiple samples of each of these stock
pistons. Honda parts have excellent machining clearances right from
the factory. For example, the standard piston clearance in cylinder as
listed in the service manual for 1995 del Sol VTEC with B16A is
.0004"-.0016". Typical aftermarket forged pistons, even if
it is high silicon for better clearance would be .002"-.003".
BTW, the .0004"-.0016" not only applies to the
high performance DOHC VTEC engines. The manual shows that the
lower-specific output D motors also feature the same high clearance specs.
Engine &
Piston Stamp |
Compression
Height |
Dome
Height |
Weight
(grams) |
Bore
Size |
| B16A PR3 |
1.180" |
0.098" |
299 |
3.188" (81.0 mm) |
| B16B PCTX |
1.210" |
0.253" |
327 |
3.188" (81.0 mm) |
| B17A P61 |
|
|
|
|
| B18B PR4 |
1.180" |
-0.055" |
280 |
3.188" (81.0 mm) |
| B18C P72 |
1.183" |
0.000" |
305 |
3.188" (81.0 mm) |
| B18C5 P73 |
1.190" |
0.070" |
310 |
3.188" (81.0 mm) |
| B20B |
1.165" |
-0.035" |
312 |
3.307" (84.0 mm) |
We weighted many wrist pins and the average weight are
88.2 to 88.8 grams.
For a good intro on pistons, read this offsite
article on Pistons by Performance Professor. It also gives some
thoughts on piston rings.
