Anyone use Nippon FRM pistons?
04-09-2018, 04:24 PM
#31
In another thread, Chis Barry said this regarding the f20c FRM wall.
The only problem with the Nippon Racing Pistons is that the pistons are Cast, while the OEM piston in the F20c is Forged. I know that they advertise their treatment etc. makes the piston much stronger or equal to OEM pistons. I know the Mrsideways had issues running RSMachine pistons in one of his K20 builds, which I suspect are really Nippon Racing Pistons. Please update with more info fatjoe once you get it running!
The bores need to be honed using special diamond impregnated stones, its then polished using brush like abrasive tooling.
The FRM layer is thick enough for at least +0.5mm bore which should cover most minor damage. From memory the honda oversized pistons are +0.25mm.
Pay special attention to the piston/bore clearances. Try to keep to recommendations for the pistons being used.
The FRM layer is thick enough for at least +0.5mm bore which should cover most minor damage. From memory the honda oversized pistons are +0.25mm.
Pay special attention to the piston/bore clearances. Try to keep to recommendations for the pistons being used.
04-09-2018, 05:02 PM
#32
In another thread, Chis Barry said this regarding the f20c FRM wall.
The only problem with the Nippon Racing Pistons is that the pistons are Cast, while the OEM piston in the F20c is Forged. I know that they advertise their treatment etc. makes the piston much stronger or equal to OEM pistons. I know the Mrsideways had issues running RSMachine pistons in one of his K20 builds, which I suspect are really Nippon Racing Pistons. Please update with more info fatjoe once you get it running!
The only problem with the Nippon Racing Pistons is that the pistons are Cast, while the OEM piston in the F20c is Forged. I know that they advertise their treatment etc. makes the piston much stronger or equal to OEM pistons. I know the Mrsideways had issues running RSMachine pistons in one of his K20 builds, which I suspect are really Nippon Racing Pistons. Please update with more info fatjoe once you get it running!
04-21-2018, 11:39 PM
#33
So the Nippon pistons just arrived from the coater. I got enough parts to build 2 of these engines right away. So now the question is, should I pair the Nippon pistons with the 99mm stroker kit (left rod) or build a 11.8ish CR F22? Decisions decisions...
04-22-2018, 06:22 AM
#34
Thread Starter
Personally, I would not use the cast pistons on the stroker. The side load on the skirt is much higher from the rod stroke ratio...unless you're just doing it purely for experimentation. In which case, if the CR is 11.8 on a f22 it'll be higher on the stroker
12-20-2018, 03:15 PM
#39
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I am just about to build an F24C with nippon 87.25 pistons (FRM honing using OEM Honda 87.25 rings and new Honda pins). I am concerned about side load AND piston pin area strength as piston acceleration with the 99mm crank is very high. Fatjoe10 any news from your buid? I am planning to rev limit the engine at 8200 or even lower to keep mean piston speed below 27m/sec. I hope the pin boss area will hold. I am also using a thicker head gasket to bring down compression to a reasonable level for cast pistons (1mm or 1.25mm).
12-20-2018, 04:15 PM
#40
Thread Starter
I am just about to build an F24C with nippon 87.25 pistons (FRM honing using OEM Honda 87.25 rings and new Honda pins). I am concerned about side load AND piston pin area strength as piston acceleration with the 99mm crank is very high. Fatjoe10 any news from your buid? I am planning to rev limit the engine at 8200 or even lower to keep mean piston speed below 27m/sec. I hope the pin boss area will hold. I am also using a thicker head gasket to bring down compression to a reasonable level for cast pistons (1mm or 1.25mm).
For reference on the weight difference on different engine components I documented my F24 build here: https://www.s2ki.com/forums/s2000-fo...diary-1187042/