I have one Revo. The size specifications is the same as Savage. Tires are bigger on the revo such is big joe.
Length, width, and so on are 1/8 but scale sign is 1/10. I do not why, but I thing because Revo is using smaller engine: .15 cubic inches such another 1/10 models.
But dont worry, this engine have 1.33 horse power and revo is albe to do wheelies.
More small engine can run on smaller % of nitro. Smaller engine uses smaller fuel tank, smalelr engine have smaller consumption. So, smaller engine save your many because 16% nitro fuel is not expensive as 25% nitro fuel for .21 and bigger engines. Smaller capacity of sleeve save money again, because consumption is samller. Smaller consumption = smaller fuel tank.
And you can belive me, this stock engine TRX25R is very powerful and you will get a lot of fun with it.
If this engine is not acceptable for you, you can sell him and buy big block conversion kit to get opportunity to use bigger engine such is HPI Nitro Star .25 which is in Savage SS.
My friends have savages (here is more savages than revos) but the confrontation we do not do in this moment, but we plan to make comparsions at the track.
Question is, if you really need more power. I am not racer, I am basher and RC truck trial driver and .15 in the Revo is adequate.
I am using Graupner Titan RS16 with 16% nitro. This is syntetic fuel with 4% ricine (castor oil). And it is going very good and fast. This fuel is accessible in Europe.