Block sizes

[2revo1maxx]

I know that there are typically 3 sizes for nitro engines, small, medium, and big. I've heard that the trx 3.3 is a medium. I don't know if it really is or not, but a picco 21max is slightly larger overall. My sirio s27 is advertised as a mid block but is way larger than my 21max, and has a big block exhaust and fits my revo like it was born there. I know a big block is bigger than that, I've seen them. Do they just go by displacement? I seem to remember a time when a 21 was a big block. Thank you.

 

[olds97_lss]

These days, it has more to do with it's foot print and displacement. If the displacement is more than .18ci and it fits in a small block space, then it's a mid-block. If it's .18ci or smaller and fits in a small block place, then it's a small-block. If it's more than .18ci and does not fit in the space of a small block, it's a big block.

Has gotten kind of fuzzy over the past few years since t-maxx's "mid-blocks" came into play. Now there are more brands/sizes that are "drop ins" for the t-maxx/revo trucks. Some require a bit different mount, but most that are considered a drop in that are larger than .18ci are your mid-blocks.

 

[2revo1maxx]

Yeah fuzzy is right, but I see it's mainly with the mid blocks, thanx.