New engine lacks power

[Kmitch36]

Have fresh rebuilt in my 97 k1500. Shaved deck 15000 and bored 30 over,now acts like it has no power.was getting misfire code in 1 & 3 new plugs ,wires,dist.etc.only thing used is intake could this be a fuel problem or possibly crank pos. sensor problem?

[00Silverado4x4]

Yes to both questions. Could be either or worse both. Check them both out to make sure everything is where is should be setting wise.

[GMstrong]

i would start with the fuel pressure.

[Kmitch36]

Ok,will check all three

 

[Duelin]

Don't over look mechanical problems since the engine was just rebuilt. Did you do it or was it done by a machine shop?

[Doug_Scott]

Always start with basics, you need fuel, compression and spark. Remember, new parts can be defective.

As someone already asked, who assembled the engine? Who installed it and got it running? If it was not you, take it back. If it was you, how confident are you on the assembly\installation on being done correctly? How confident cam timing it correct? What about valve lash (assuming it is adjustable)?

Are engine components stock spec? You said it was 0.030 overbore, and deck height -0.015, is cam stock profile? Stock compression pistons (other than CR increase from decking and overbore)? If you have a non-stock profile camshaft, and a stock torque converter you may run into a sluggish condition from idle up to above midrange, with power coming on then.