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  1. #1
    RC Enthusiast
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    Question New to me T-Maxx

    Have a new to me T-Maxx thatís used, but in great condition. Itís been about 20 years since my last nitro. Weíve been running slashes, 4x4 Stampedeís (one VXL brushless) and decided to get our first nitro. Hoping to get some feedback on the following?

    1.) Nitro fuel? Whatís everyone using and recommend?
    2.) After-run oil or WD40? Seen several you tube videos showing both and wanted to see what everyone else is doing as I never did this on my old nitro engines....I know, I know this was wrong but I was only 15/16 at the time and just ran the mess out of them.
    3.) Going to set the carb to factory specs and then tune in from there. What temps are you guys seeing when dialed in?

    Thx!

  2. #2
    RC Qualifier westoakmech's Avatar
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    I run vp power master 30%. It is what is the most readily available to me. I have ran traxxas top fuel, and morgan fuels. Morgan fuels used to make top fuel, have not seen a top fuel jug in awhile, so not sure if they still do.
    The most important to me is to run what I can get easily, and not have to change and retune.

    I use wd40 for after run oil, works great. I think almost any light weight oil will work, some use marvel also.

    Once I get one dialed in, I try to keep my temps around 250. 270 is where you will start doing damage. Some engines do like to run up there closer to the 270 mark. I tune by smoke, sound, and performance. I use the temp gun as a reference. Like I said, I have had some that perform best right at that 270 mark, so every engine is a little different.
    Rusty 2.5R,T-max 2.5 & 3.3,Summit VXL Nitro 4-tec

  3. #3
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    Thx westoakmech, figured WD-40 and I keep marvels around for everything under the sun except personal consumption ��. It’s great to cut with 3-1 oil for a super light electric motor bushing oil. Will also have to develop the ear for the nitro as I do 2-stroke repair and learned to tune by ear. The temps help keep me out of trouble.

  4. #4
    RC Champion MaXXL's Avatar
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    If you plan on storing your engine for a while, you may want to use a thicker after run oil like marvel. Lighter oils will tend to run down into the crankcase rather than staying in the combustion chamber.

    And yes buy whatever fuel is readily available near you. More oil content is better to a certain degree and as for nitro content: try to run what was previously used. If you dont know what was used last start with a lower nitro conent and work your way up.

    Tune the engine with a half tank of gas as well. The tune leans out as the fuel level drops so if you tune it at a half tank you'll be running a bit rich with a full tank and a bit lean with an empty tank. Better than running perfect with a full tank and very lean with a half tank.
    10 RCs and counting 😅

  5. #5
    RC Qualifier westoakmech's Avatar
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    +1 on the half tank tune. I run a different tank, so I always forget about the half tank tune. It can be frustrating chasing the tune sometimes if you don't take that into account.
    Also keep your air filter clean. I keep spares in a zip lock bag pre soaked in oil. I can just change out, and then clean and store.
    Rusty 2.5R,T-max 2.5 & 3.3,Summit VXL Nitro 4-tec

  6. #6
    Marshal Double G's Avatar
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    Quote Originally Posted by SlashRunner80 View Post
    1.) Nitro fuel? What’s everyone using and recommend?
    I've ran O'Donnell's and Byrons. Since my LHS hardly sells nitro I had to pick up some Blue Thunder and have yet to use it.
    Quote Originally Posted by SlashRunner80 View Post
    2.) After-run oil or WD40? Seen several you tube videos showing both and wanted to see what everyone else is doing as I never did this on my old nitro engines....I know, I know this was wrong but I was only 15/16 at the time and just ran the mess out of them.
    Carefully read the manual for your engine. Some recommend not to use WD-40 because of o-ring degradation. Traxxas says it is okay. For my OS engine I use after-run oil.
    The Super Derecho

  7. #7
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    Interesting on the half-tank tune as I figured it wouldn’t change till the tank was almost empty like 2-stroke engines. Are any of your guys running fuel filters? I picked one up to keep trash out of the carb.

  8. #8
    RC Champion MaXXL's Avatar
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    Some people swear by fuel filters, others say they only cause problems.

    I have never used one and dont feel i need one. I feel like you would have to be very careless to accidently get dirt in the tank.
    10 RCs and counting 😅

  9. #9
    Marshal Double G's Avatar
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    Quote Originally Posted by SlashRunner80 View Post
    Interesting on the half-tank tune as I figured it wouldn’t change till the tank was almost empty like 2-stroke engines.
    I look at it like this: air can be compressed. Unlike your gas 2-stroke engines, RC engines use exhaust pressure to push the fuel to the carb. As the tank drains there is more volume of air that can be compressed and less fuel going to the carb. If you get a great tune at full tank it may be very lean at empty. After first start, warm the engine up and then start tuning when it is at temperature and around half tank; then you will have a slightly rich tune at full and slightly lean at empty.

    As for fuel filter: I did when I had a T-Maxx. Now that I have a Revo it has a built-in stone filter on the pickup tube.
    The Super Derecho

  10. #10
    RC Qualifier westoakmech's Avatar
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    I ran an inline filter once, and had problems. It would make the engine run lean. Was clean, and big enough for the application. It just caused enough restriction to cause problems.
    I run an associated fuel tank, and it has a built in stone filter. It used to be a must do mod, to run the ofna violator tank. I don't know if you can even get that tank anymore though.
    Rusty 2.5R,T-max 2.5 & 3.3,Summit VXL Nitro 4-tec

  11. #11
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    Wow this thing is wicked fast and ran pretty good on the factory tune. Worked a little on adjustments and kept a 240 temp even without the windshield cutout mod for more air flow. No issues so far with the inline filter, but bought a name brand one that had good reviews. The truck did come with new RPM front arms and pins.....and was like sweet, until the first run and a hard turn. One of the bottom arms was cracked and had a bent pin. Two hours to change out both sets of front arms and it’s good as new. Going to put some time on it this weekend for sure.

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