my z28 has almost 134,000 miles on it, i was talking to my friend today that is a mechanic, he said if i wanted to get the most horsepower is to get the engine overhauled, is it worth it to get it done ?

 

It depends on the condition of the engine. I it running smoothly? How is the oil pressure? Is it leaking fluids? Is the compression OK in all cylinders? 130K mles on a well maintained engine that is not abused, and mostly highway driven is no big deal. However; if it was abused, poorly maintained, and driven in city traffic, it will probably need to be rebuilt. Rebuilding a good engine is going to add little if no power, rebuilding an old clunker will definetily result in a power boost.

 

well i bought the vehicle in january with 127,000 miles,it wasnt in the greatest condition but it still ran well, i have had the cat converter replaced, opti-spark, water pump, front seal, spark plugs and wires, valve cover gasket, and intake manifold gaskets, and had the differential rebuilt.it does run pretty good now, i did plan on getting some better flowing heads and having the valves replaced.it isnt leaking any fluids, i havent had the compression checked, but fuel pressure is good, i do monitor the oil pressure on the stock gauges so im not sure how accurate they are but at WOT it stays about 60 im assuming psi and at idle it is in the 20 range

 

Sounds like a pretty decent engine to Me. If it's not smoking, overheating and maintaining good oil pressure, It's in good shape. Do a good tuneup, change to fliuds and press on.

 

yes, it doesnt smoke at all and hasnt since i owned it and it has never over heated gets to the half way mark and thats it, thanks for the advice

 

Sounds like your engine is in good shape, so I doubt that a rebuild will result in a noticeable power increase, if any.