1.What is default rpm value for d15z1 vtec-e engage?can i adjust it?if can, how?
2.How my d15z1 vtec-e function?What's the different with d16z6 vtec?

[ look my friend the maximiu RBM for the D15Z is 7200 . and you can not adjust it else by changing the ECU ( ELECTRIC CONTROL UNITE )
else that you can make things make the acceleration better like using splitfire wich desine for the D15
the vtec is variatino valves timming and electric control

thet mean every thing in electric . vtec is 3 stage

1 from 0rbm to 2800 rbm ( nearly ) your motor is work as 12 valve
and of cource few feul and littel power
2 from 2800 rbm to 4800 nearly rbm it is work 16 valve as the d15b non vtec
3 from 4800 rbm to 7200 rbm and this stage is wich harmless for the youth it give great power to the engine and you will see the rbm run into the 7200. that vtec iam not sure what is the vtec-e
Hany

wtf is rbm. i think u mean rpm? vtec-e means at low rpm theres only 3 valves opening, mid range all 4 valves open then at high rpm regular vtec engages. or something close to that
http://asia.vtec.net/spfeature/vtecimpl/vtec1.html