I have a 2000 discovery, it has a blown head gaskets. Should I rebuild the heads r buy a used engine wit 90k on it. Mine has 146k. Now if u rebuild the heads will the new combustion pressure have n impact on tha bottom half of the engine. Both will cost rnd tha same. What should I do?

 

Just replace the head gaskets and be done with it.
$500 DIY.
$1500 at a indie shop.

 

I no n tha past wen I had a new head put on rodeo it wldnt run rite cus of all the new compression frm the new head was 2 much 2 handle on the bottom half of tha engine. Unless I get tha whole thing rebuilt.

 

Replacing the head gaskets won't change the amount of compression other than in the cylinder with the leak. Rebuilding the heads will raise the compression if the valves are in bad shape, and it is possible that the increase in compression and subsequent increase in power can put additional load on the rings and bearings. If that doubt exists, replace the head gaskets only and do a major overhaul some time in the future.

You know what you have with the existing engine, and that amount of mileage suggests it has been cared for. The replacement engine is more of an unknown, and you may be doing repairs you are not prepared for.