Homemade WRX

I really won't guess now, considering I still have a few key questions on the bottom end.

Sorry another question, how high do you reckon the motor can rev with its current stroke + upgraded rods? (only asking how much the bottom end can take) Using my calculations of 131mm rod.

yeah, that's about right. Usually my 300M rods are for a higher power rating, so I don't have a direct number of same power to weight for you...15-20% would be the ballpark in weight savings. But since I pair it with a lighter piston and several other changes, it can lose more weight.

What kind of weight reduction are we looking at? :O
Just going by fatigue limit maybe 10-20% seems possible, over 4340.

No, they reduce weight and add strength. The beauty of good material and design. If I wanted to marginalize strength, I'd simply run aluminum

Am I right in speculating that the rods you plan to make are supposed to cut weight as opposed to add strength?

300M just costs that much more...it's roughly $50/rod more to produce. Since most don't want to pay for it, or gripe about pricing, it isn't worth most places time to stock it. OR they can simply get the strength in 4340 by making a beefier rod, requiring less machine time as well...no skin off of their nose. Cosworth and I (3MI Racing) actually use the same rod manufacturer btw.

Hey Homemade WRX, so I had a question since you mentioned 300M alloy rods. I noticed that it's pretty hard to find 300M alloy rods for most cars, almost all of them are 4340 instead. Some guys claimed their 4340 was 300M spec. Cosworth uses 4340 alloy. Am I just horrible at Google searching or is it just that unpopular?