b4 engine vs Gen 4 engine

[JMlegacy]

I had to do a rebuild and it kind appears to me that the bottom half is from a B4


IF not, can anyone Identify those pistons?

IF it is indeed from a B4, are they any weaker/stronger than the Bl5 / Gen4 legacy GT engines?

[dr20t]

Per your other thread, I was shocked to see this block

Looks like a version 5/6 open deck jdm ej207 block from an Ra Sti

I'm pretty sure these were the blocks that came with forged pistons marked hsb but will double check

[dr20t]

From this post looks like I was mistaken - the jdm v6 ej207 with forgies had hb not hsb and no valve reliefs:

http://www.perth-wrx.com/vb/mechanicals ... ild-6.html

I remembered the letters hsb and a pic of an open deck block with forgies from my research over the years, and thus why it rang a bell. Looks like yours is different though.

If they told you its from a b4 then you have an ej208 / ej20h block from the TT legacy b4 - open deck 9:1 compression cast pistons. If late model gen 3 I think they came with 9.5:1 as well, but not 100% sure on this maybe Australian market only.

Your gen4 jdm ej20y has 9.5:1 static comp and semi forged piston (crowns)

[JMlegacy]

Oh I see.