I am starting my 390 build up for my 66 Tbird with advice from all of you. See previous post of "FE Mild Racing Buildup" After many responses, I had chosen the Crane cam 341191 and the TRW L2291F pistons. My engine builder will build to my specs, but highly recomends against any TRW pistons. He says that the weight of the TRW vs the Keith Black hyperertectic is the biggest factor. That the Keith Black is far lighter and stronger than the TRW. He says the TRW pistons are "old school" engine building. Telling me that if I insist, we can install them, but really wants me to rethink the decision. The TRW pistons are slightly cheaper, but not enough to base the decision on only. He says that if I want forged pistons, I should spring for the JE pistons for around $600. Now I know that some of you regular guys on the FE forum here use the TRW pistons with wonderful results, but is there any reason I should not run with the Keith Blacks? Has anyone used the Keith Black hypereutectic and liked or disliked them? Are the TRW pistons superior, or just more popular? The only other factor is that Keith Black pistons come in 020, 030, 050. The TRW come in 010-060. I am currently bored 030, and will most likely go to 050. RS, DF, or anybody have an educated guess for me? Maybe I won't be able to tell the difference? I would like to order pistons in the next day or two, but now I don't know who to give my hard earned money to.

 

Well I can see where the KB pistons being lighter is an advantage. I really don't think he is right about the strength. The KB pistons are great for performance builds but if you are going to run massive amounts of nitrous then you need forged. TRW are not the strongest forged pistons on the market but still I am pretty sure that they will handle more of a power adder than the KB. The best way to know is to call KB and ask them if they are good for a 250 shot of nitrous. I'm betting that they will recommend a forged piston.

 

If your engine is going to have a power adder, especially nitrous, get the forged pistons. Hypereutectic pistons, while better then stock cast pistons, are still cast pistons.