Let's look at today's engines. In this case the 572" Wedge that Ohio Crankshaft built for us. It has a World Products aluminum block, Ohio Crankshaft 4.500" stroker crankshaft, Ohio Crankshaft 7.100" Chevy journal rods and 4.500" JE SRP Pistons with Total Seal 1/16" rings. It’s designed to be very durable and last a long time.
I made the call to Stan at Ohio Crankshaft about his thoughts on when to freshen an engine like this. We talked for a little while and I asked about the life expectancy of the aluminum rods, the rings and bearings. What should I look for, what is the life expectancy, etc.
After listening to Stan I have decided the best course of action is to "leak" the engine and check a couple bearings before doing anything else. Stan's one comment that I liked was that if the performance of the engine has not fallen off and oil pressure is consistent, there should be no reason to just take the engine apart for the sake of something to keep myself busy in the winter months. As for everyone's fear of aluminum rods, they should last as long as your aluminum pistons if treated correctly. The exception would be, in my opinion, if you use nitrous or other power adders; the aluminum rods are lighter and are absorbing some heavy detonation and load in those engines. If you do this to your aluminum rods I would look to change them at 150 runs but by then you are probably needing rings and bearings anyway. The days of replacing aluminum rods every 150 runs in a naturally aspirated engine are a thing of the past, in my opinion. If I am wrong, you will read about it in this magazine next summer.
I just finished the "leak-down" test and it was right at 4% per cylinder. This is very good and probably why this engine was running 7.53 at 176 mph the last weekend. I will take the pan off next week and see what the main and rod bearings look like that are the farthest away from the oil pump. If they look as good as I think they will I will reinstall the pan and get it ready for 2009 without tearing it all apart for what might be no reason at all.
If the basic inspection shows the engine is good to go I will save about $2500 that it costs to freshen an engine. That $2500 will cover all my entry fees and most of my travel expenses to local races next season. That is a "savings plan" I can relate to. I am thinking about putting that savings into some spare parts, like a spare converter, some valve springs, etc.
Of course, I don't want to risk the engine just because I didn't tear it down. On the other hand, it seems to have been assembled by Ohio Crankshaft in a manner that is creating good horsepower and reliability. How do I know we can get the rings to seal that good again? You don't; you just hope you can. So, until I get some signs that we are starting to wear out that 572" Wedge I think I will put some oil in the cylinders, take the rocker arms off and clean it up.
I am convinced that even a 1000-HP engine, built with top quality products, should go 300 to 400 runs without the expense of a rebuild just for the sake of a rebuild. We will find out, as the decision has been made.
Maybe it's time to reconsider tearing your bracket engine down to see if it is okay. Trust the quality parts and keep that money in your pocket so you can get out there and race at some events in 2009.
Good luck, and we'll look for you at the track next year.