hi guys. i'm a newbie here driving a 180sx once fitted with a ca18det engine. ever since i did an engine swap over to an s15 sr20det together with its six speed gear box and stock ecu, i have experience problems such as very high petrol consumption, a power lag from 2000 to 3000 rpm and my speedometer cant seems to work. ive brought it to several workshops over in my country(singapore) but none of them know what is exactly wrong with the speed meter. some suggested to get it tuned while others recommend me to have change my speed meter panels to s15. another probable solution was to change the rear gear box to the s15 one with LSD as the s15 runs the meter from its rear gearbox.

does anyone here have encountered this problem before or know of the solution ? cos i need to fix this problem fast before the authorities in my country finds out about the engine swap. any help is deeply appreciated. cheers.