Originally Posted by delkat
Are the OEM pistons, rods and crank forged or cast? Is the block sleeved?
The components look stout from the pictures. There's a lot of mass in the valvetrain with the chains and Vanos components. How does the combustion chamber/port design/valve profiles look? Do you think the roll off of power at redline is due to head flow limitations, valve size, cam profile, a combination? Just wondering where the best bang for the buck is to get more power out.
Most of the stock components in this motor (S65) are not forged, the stock block is not sleeved. The S65 was designed to be a light and naturally aspirated high reving motor. So when we decided to start adding high boost to a motor like the S65 we already had taken this into consideration.
The stock S65 heads flow very well from factory and the rev limiter set on them is still actually very conservitave. Our company M3 vehicle has a rev limiter set way above the factory limit. The power loss up top is all due to tuning, nothing to do with the flow of the heads. The factory heads are capable to support well over 700whp.
What many people dont know is that from the day we finished and started testing our bolt on SC kit back in 2008, we had already taken apart an S65 motor and started doing heavy R&D and testing for High boost applications. We tried several different set ups for high boost, from using a stock block with lowered compression Mahle pistons to Sleeving the block and trying different brands of Forged pistons until we found a successful combination. The problem we found when using just the stock aluminum block and Mahle pistons was they could not handle the boost levels we were trying to accomplish. When doing our testing we saw signs of the cylinders becoming deformed and leaving marks on the sides and skirts of the pistons. This was caused because the aluminum block was flexing too much when pushed hard. That is when we started sleeving the stock aluminum block with cast iron sleeves and since have been able to push boost levels upwards of 20lbs thus far.
Some believe sleeving an aluminum block with cast iron sleeves weakens the block, but we beg to differ. We speak from actual experience and testing, not from opinions and theories that may be bias. We would not be doing this if it wasn't neccesary. Sure you cut away at the stock block but you are re-inforcing it with Cast iron which is much stronger than aluminum. We also would never consider using stock rods on the boost levels we are pushing and trying to accomplish. Why take apart the whole motor, build it and leave the stock rods? Doesn't make sense to us. We have also changed and updated a lot of other stock parts that we found as we went along were not getting the job done. We are not gonna take short cuts just to save our customers a couple hundread dollars on a 30k+ build.
Our goal is to push this motor as much as possible and do what everyone calls "impossible". So far we have been very successful with our motor builds and we are still to this day working on pushing even more boost than what we have made available to the public. We are far from being done. We want M3 owners to be able to not only compete but be able to defeat any other supercar or F/I car with claimed 800+hp. We know we are the under dogs because we havent been around as long as other companies have but I can assure you we are here to stay. We are doing whatever it takes to accomplish our goals and prove our products are just as good if not better than our competitors. We are hard at work everyday and we hope to expand are FI options in 2012. We want to offer not only more power but road/track tested reliability.
Hope this clarifies some questions and concerns, Thanks and Happy Holidays!