if you want a drag car definately go for the rb 26 or 25, if its a road car you're after i'd suggest the sr20 or even turboing your ka. as far as swapping the rb motors in goes the rb 25 isn't that hard, most ppl blow that out of proportion all you really need is someone who knows their shit and a motor mount kit that can be bought from mckinney motorsports and a few other places. Mckinney even makes one for the rb26 if you choose to go that way and the rb 26 is very doable if mated to the rb25 tranny with the rb25 oil pan. Both rbs will require a shortened driveshaft, you can use your stock one with the correct length measurements and the rb tranny's yoke up front most driveshaft shops should be able to do it. If not the rb engines then sr20 or turbo ka. Turbo ka is more cost effiecent cause you can spend the $4 to 5 g's on buildin up the ka with a mad turbo and honestly lookin at like 300ish horses instead of spending all that money for a bone stock sr20. but whatever you do it's awsome to see a serious 240 around here.
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