Dude if ur putting the car into a 4th gen civic or 2nd gen CRX, ull b fine. they weigh 27lbs more than the stock 1.6L Si engine. also the torque they make will compensate for any loss in weight u have. LS engines are nice man. if ur doing an LS swap for a 91 and lower Civic/CRX. ge the 92-93 LS, it has 13 more hp and a way nicer torque band. u must convert it to OBD1 tho, but its worth the extra hour ull spend re-wiring it.
Actually the 92-93 is obd I if he was converting it'd be to obd 0 anyway I missed where he even said what car he is swapping into.So all this could eb wrong info as we started with nothing other than a question about weight.