I think it truly depends on experience. Are Keith Black Hypereutectic Silv-O-Lite pistons any good etc.? Keith Black Performance Pistons. Keith Black makes a high end hyper piston. I have cast 10:25 to 1 flat tops now. This makes them not only light weight but extremely durable. You can now use the stock 4.0 rods with the Keith Black "ICON" forged pistons, because of their wrist pin location. The Keith Black pistons unique thermal conductivity, ring location and varied end use requires special attention be paid to top ring end gap. I trust his knowledge just wanting to see if anyone esle has had the same problem. For theirs, they recommend a much wider top ring gap. I stumbled across a very informative 4.0 stroker page from some Jeep guys, and you no longer have to use the 258 rods. Bought a set of KB pistons(9.2 to 1) for my build and curious if anyone knows what the 2 extra rings that came with the set are for. Some people say they are fine if you install the rings properly. Ive had some people say speed pros arent the best. Do you think either brand others a distinct advantage or disadvantage, in terms of reliabilty and performance. If you had a good one you praise, a bad one you bash. What are your thoughts on Speed Pro vs KB hypereutectic pistons for street performance use, say around 450 to 475 hp range. The pistons are Keith Black hypereutectic 10.5:1 cr. I'm in the market for pistons. Made from hypereutectic 390 aluminum alloy, Keith Black Signature Series pistons are CNC-machined for accuracy and are heat-treated with 16 to 18 percent silicon. When rod tries to pull the piston back down, it chunks off the top ring land. Top. Since 1922, United Engine and Machine have been building a reputation for their pistons of the utmost quality. 115 Posts . Thus, they carry and manufacture Keith Black pistons. Keith Black Silvolite and Federal Mogul/Speed Pro are the main players in the hypereutectic piston market, and we have used both brands in … Now, don't misunderstand, Keith Black hypers are good pistons, I just personally don't like that big gap required for their top ring. 319 Posts . They have several different stroker build options/combos listed, from mild to wild. Keith Black also offers KB Signature Series performance pistons for Ford, Chrysler and GM muscle car applications. If you don't use the wider top ring gap, they ring ends can butt at the top of the cylinder (hottest part) and stick. My machine shop guy said this is a common problem with these pistons, and KB blaims it on tight ring gaps. I use Speed Pro (Federal Mogul owned) hypereutectic pistons which use a normal top ring gap. Discussion Starter • #1 • Nov 6, 2004. KB pistons make more HP by reflecting heat energy back into the combustion process and, as a result, the top ring runs hotter and requires additional end clearance. These pistons mostly contain high silicon aluminum alloy. I've never seen a problem with them. Discussion Starter • #1 • Apr 27, 2007. Or can anybody suggest a brand. Had oil consumptions problems on pretty new 408sbc. I hear bad things about Keith Black Hypereutectic Pistons. HP fan Member Posts: 91 …