Topic: any special name?

[Sopcich04]

is there any special name for a pontiac 400 engine? like the chevy 350 is an ls1/lt1 and i think corvettes had codes like L88(maybe).....just wondering on that

[chris189]

The base 400 Pontiac engine was called an L78 as the performance package that boosted it to 200 or 220 was called W72.  Hope that's what you were looking for.

[rkellerjr]

So my '77 400 base engine is a L78?

[chris189]

Far as I know, you have to check to passenger side front of the block right below the head for two letters stamped.  Then look on the net for what your letters mean, could be something like yx or yv, something like that.  Mine is a '78 with WC which means it IS a W72.

[rkellerjr]

Ah, gotcha, mines a Y4 then.

[kyledyr]

the LS1 and L78 and the such are called RPO codes, i believe.  rich, your RPO code IS a L78.  if someone had the "performance" engine, its called a W72.  my little chevy 305 is called an LG4.

[ta78w72]

Both the "W72" and the standard are L78's, one has the performance package...but the same basic engine.

[John Witzke]

W72 was originally going to be called LS7