Quite a few years ago,before I used the internet, I wanted to put together a long rod 400 but there was nothing available over here at a reasonable cost. What I did was buy 10 used ali rods off the 'parts for sale' bench of a blown alky or fuel racer ( Raymond Beadles Blue Max was the car,I believe it came from the States)at one of the bigger race meetings. They were 7.030" long,Brooks manufactured and not all from the same set,and of course Mopar dimensions. I measured them and none had seemed to have stretched so I crack tested them and they were fine. After a fair bit of machining they were fitted using LIGHT Chevy 400 pistons and a factory cast crank. Well I ran that engine for over 5 years in two different cars,7000rpm on every pass,100's of passes into the 9's for the last two years. Every year I maintenance checked the bearings and every year they looked great so they went back in. So much for needing to change them every 10 minutes! The engine is still going strong today. Ok,it was only making about 575hp,but that's my point-the rods were good to 8 or 9000rpm in a 2500hp engine so my piddling 575hp wasn't even tickling them!
Using ali rods is more than just about light weight,they have more bulk around the big end,they absorb shock loads in the event of a little detonation,are easier on bearings and rod bolts. British bikes regularly used ali rods ,in the road and race bikes and none of the manufacturers specified changing rods on a regular basis. I get sick of hearing "OOH ali rods,you need to change them every 70 passes" from other racers!
The new ali Brooks rods in my turbo combo,which I expect to make 1200hp, are said to be 2500hp capable and I have no intention of changing them unless they give me a problem.
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