i'm also been thru tis dilemma..... finally go for 1JZ also
Dun mistaken i'm on 1jz transplant now, b4 tat is sr20det (drive for 2 years ++) on volvo 240.
Speaking on power (everything stock wif ori 3.77 final drive) sr20det on ~1400kg chassis, totally not impressive.....
Pls consider the cost to make 300hp out of sr20det (S13 redtop) compare to 1jz-gte, then u'll realize
(unless u rich lah). Dun say stock (200hp) is enuf ... Everybody chase for power... garenti punya..
Part availability is also an issue, definitely 6 cylinder will cost more than 4 cylinder. eg. water pump for sr20det is 200++ while 1jz somewhere around 1700++...
SR20 oil sump ngam ngam clear volvo 240 but 1jz need to mod a bit even the rear type punya
(volvo steering rack is in-front of the cross member).
So if in merc body, i vote for 1jz anytime,
if KE70 leh then sr20det loh..