Barrel differences?

[e30 gangsta]

Hey guys thinking about buy a spare set of barrels to send of to machining for my new engine. Small question though, are the barrels the same for all years of the xs? Thanks.

[bikerphil]

I want to say yes they are all the same. The pistons vary between the early and late motors only due to the dome top.

[Fields11789]

I have a set of jugs from a 78 on my 81RH. Swapped straight over without any issues.

Pistons fit in just right too. I saw no difference in the two I have.

[motoman]

I have a set of jugs from a 78 on my 81RH. Swapped straight over without any issues.

Pistons fit in just right too. I saw no difference in the two I have.

Head itself is where differences are........combustion chamber volume and intake/exhaust valve sizes. Along with that, 78-79 have different cam profiles....duration, lift, overlap timing, etc..

[mack]

Get a

bore gauge and measure them first. Tolerances are listed in the manuals. You need some life left in them because you should deglaze the walls with a honing ball or may have to rebore for a larger piston set. Sleves are available and if your significant other will let you use the oven, it a fairly quick change.