The 2604/ and 2601 are the same pipe with different logos on them. I am pretty sure that the Max 2602 is the same too. The Novarossi is the 2601, and the RB is the 2604. These pipes give slightly more bottom end than the 2630. The 2630 has a little more peak power, and makes it's power higher in the rpm range than the 2601.

Fuel mileage is very hard to predict for each person. One pipe may give you more power, therefor you are less aggressive on the throttle. Sometimes this can get you better fuel mileage than using a pipe with less power, and runtime because you are always on the throttle sucking the fuel.

The 2630 will also run out of fuel about one lap earlier than the 2601. Everything else being equal. Say 15-30 seconds more with the 2601.

great!
just the info i needed as well.

what's up guys I have a 35plus21. Has less than a gallon including break in, and the piston looks like this is that ok.

It looks really good, that's a perfect!

looks a little lean... ?

Really depends on what fuel you are using. For example in my racing engines i run Runnertime fuel, because of the special oil's it gives the entire engine a lightly brown colour.
But when i use Tornado on the practice engines it burns completely clean, even when i ran them a tad on the rich side.

But your engine looks good, if you will run the engine with this colour it will last quite a while.

Actualy the dark color comes mostly from castor oil. Running with synthetic oil wil give a much lighter color.

In my own personal opinion... When my piston reaches that color... I always take a polisher (Blue Magic or similar) and remove that carbon buildup. Always making sure not to touch the sides of the piston. I do this so the next time I run, I can look at the piston and know if it was ran too lean or too rich. Many people have different perspectives on this matter, some say that carbon buildup is not supposed to be removed... But hence why I started this paragraph with "My own personal opinion"

I leave the carbon coating alone, only if it starts to build up a crust layer on the top, then maybe remove it with polish, but never touch the sides. The crust layer will actually start to raise the compression over time. I also look at the sides of the piston at the carbon coating. This give you a good look a how well the piston is sealing to the sleeve. You can also clean the head button and run the engine and look at that for mixture tune, but like someone else said, its the fuel you run that will have different colors or hues, so you have to know you're fuel to do this.

To all Novarossi owner, are you suppose to replace the connecting rod after breaking in the engine? this will be my first Nova I just want to make sure I get it right, the model I plan to get is 353 2008... any feedback is appreciated.

Gday, i just bought a Novarossi 3sct-tuned and i have put about 2-3L on it and that includes break in and i still dont have any play in the rod, so i guess just check it after each run and if there is play replace it.

Mitchell

change it after 5 litres, then at 10, then again at 15. after this it should be at least another 10 to 15 litres before you get any need to change. It really depends on how tight the engine is, sometimes you can get away with just a change at 5 or maybe even 10.

with plug out, put piston at top dead centre and move flywheel, the free movement when the piston is locked at top is the play, you shouldn't have too much, a small amount (maybe 1 or 2 degrees of movement) is always visible though.

"My opinion" the top of piston,n button head not that important. Clean it with the fuel you used will get most (or enough) of them off.
But if you start seeing the piston's ring getting that much ash/burn, then may be a problem.

Thanks Mitchell & TomB for your feedback...

Thanks for the info guys