2659 is released this year I think... before that all RB engines were recommended with 2604 pipe. I have a RB R3 and 2604 pipe, performance is great. Bottom end is nice but it could have been better on topend. Runtime is awesome, more than 6min on one tank easy, like 6:30 or so.
Now Im using Novarossi 2652 with R3, motor screams! All the way from bottom to top, performance is significantly increased. When I put this pipe to my car, I thought that runtime would be poor, to be honest I was not sure if it could make 5 mins... It ran out of fuel in 6:17, so I was confused, because this pipe normally consumes lots of fuel, I remember coming in for fuel in 4 min mark with this pipe and Novarossi SCT.
As its your first nitro car, I would suggest you to start with a pipe which isnt so expensive, and since 2604 is older model now, you can maybe find it cheaper.
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