Rebuild for longevity

Question

So, I have a question about a 98 2.0 rt neon. I am going to get a top/bottom rebuild on it, the block has 260000 km on it. I have seen rebuild kits on the market anywhere from 300 dollars (ebay specials) to just under 3000 dollars (modern performance). The modern performance kit is for high horse power applications (500+)

My question is assuming a professional rebuild by a machinist, if I went with the mopar kit but was only looking at tuning up to 220 hp and the cars main use would be day to day driving, how long would a rig like that last (assuming regular maintenance). My first thought would be that if a new stock engine can get 350000km then a race grade rebuild under low stress would last a crap load longer.

Does anyone have any experience/ideas for this?

I know I can do a lower mileage swap for cheap or swap a 2.4L for more power, but power is not my endgame it's dollar cost per km.

Answer 1

If you are looking for a true dollar cost per km, then do a stock rebuild on the engine. The small amount of abuse from the hp gain you are talking about can be easily absorbed by internals of a stock engine. You just need to ensure you are doing things right. There are several things you can do while rebuilding an engine which will help with longevity:

• Remove stress risers from the block and rotating assembly. Single best thing you can do for longevity of an engine. This will also lower the reciprocating weight of the engine assembly, which will help the engine rev higher and quicker.
• Get the internals balanced. While they are balanced from the factory, they are balanced within a tolerance. (After you have the stress risers removed from the engine, you'll need to get the parts rebalanced anyway.) Balancing will help keep things even between parts so there will be less vibration and power output will be equalized.
• Pay for good machining. Don't be afraid to invest a little bit of money into your block. Things like align honing the mains and decking go a long way towards protecting your rebuild investment. If you get your engine bored (for larger pistons), ensure the machine shop uses a torque plate on the block to have round cylinders as a final product of the work.
• Use micrometers and dial bore gauge instead of Plastigage to check all clearances (rods & mains). This is by far more accurate and will yield better results.

Putting money in your block is money well spent. If you build the bottom end to take it, you can later add to the top end (head work, turbo install, cam shafts, etc) and not worry about whether the bottom end can take it. Build the bottom end right the first time and the longevity of the engine will increase exponentially.