i swapped out my 305 tpi with 350 left my heads and intake on the motor new injectors and all that stuff when i started it up it left a cloud of smoke everytime i touch the gas my question is i took the plugs out gapped them up to 45 thous and now i only get a very small amount of smoke has anyone done this swap before and ran into the same problem and if so what would be a good gap on the plugs

cyl 1 had 180 psi compression
cyl 3 had 190
cyl 5 had 175
cyl 7 had 180
cyl 2 had 180
cyl 4 had 175
cyl 6 had 180
cyl 8 had 180

is this normall for havin 305 tpi heads on the 350??

What size injectors did you use and did you tune the ecm to match it? How does it run other than that?

You just uped your compression useally means less plug gap unless you have a good coil/msd/wires And yah what RED said.

The higher the compression the higher the chance of blowing out the spark, so don't go more than 34 and use plugs meant to be gapped at 34, don't use one meant for 40 and regap it to 34, or vice-versa.

i have 23 lb injectors off of jegs and am running r45ts ac delcos for plugs no i havnt had the chance to burn the computer yet but otherwise its running good just smoking alot im just kinda wondering if somone else is having the problem or if my rings/ valve seals are bad because it is a used enging and instead of just throwing more money at it and not fixing anything i would like to hit it head on the first time... i tried some engine restorer to see if anything would change but it didnt do a thing

What color is the smoke?

the smoke is blue i thought for sure it was all oil at first but after gapping the plugs some more and running prem gas some of it went away but not all of it