I got a 91 civic 4dr with a d16y8. was dyno tunning it the other night and had problems tunning because of a bad missfire. we tried to gap the plugs as low as .017, new cap,rotor,plugs,wires and it still hasnt clean up, got alittle better though but hasnt gone away. a/f was in the 12 across the board. tune was with race gas 118 octane. we were only able to make 348hp with the missfire at 24psi. no cels. missfire happens around 5k-7400. any feedback will be nice. thank you...here is the specs on the car......

obd0 to obd1 conversion
hondata s300
rc750cc
vitara pistons
tt rods
skunk2 IM
stock head
gm 3bar
obx ramhorn manifold
garrett t3/to4e turbo with 60 trim
ebay fmic
2.5 inch dp
2.5 inch ic piping
tial wastegate/bov
msd blaster2
msd 6al
oem wires
ngk bkr7e plugs gap .017
clutch master stage4
lighten flywheel



Modified by TurboSohc3369 at 1:09 AM 1/19/2007

 

anybody??????

 

Check everything in ignition try another coil, also you could do a leakdown to check for sumthing with the valves, never had any reason for my car to bend valves and i had the same problem did a leakdown and found bent valves, just a suggestion.
what do the plugs look like see if it's limited to one cylinder maybe look into the inkectors also