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Tremonic

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I have been readin pretty much everything I can about these little nitro monsters (while I'm waiting on a new engine for my recently purchased used Tmaxx) and as I was thumbing through the Traxxas site I noticed that it said their engines really like 33% nitro fuel. When I look around though I see that everyone runs 20%. Has anyone ever messed with the 33% in the Traxxas engines? If so was there a noticeable difference in performance? Does this increase the rebuild frequency? It even states that it will run cooler. Any experienced knowledge on this would be great.
 
Unless you're a hard core racer, I'd stick with 20%. IMO you don't really get that much extra power for the extra cost.
 
I agree with Ham. You get some extra performance, but less engine life. The 3.3 will wear out very quickly with high nitro. 20-25% is all you need. I've seen the results myself. My partner runs a Traxxas SCT and he replaced two 3.3 engines before he stopped usin 30%. Now with 20% he is on gallon 8.
 
Ok then. The "wear out a lot faster" response is pretty much what I expected to hear. Seems a little off to me that they would recommend a fuel that is going to kill their engines 50% quicker than the 20%.
 
In a nuthshell...the higher the nitro content...the cooler your engine will run. The lower the content the hotter it will run, but it will run longer (meaning say 10 min a tank versus 9 minutes). You won't damage your engine from running 30% over 20% unless it is shimmed incorrectly. It's like running 93 octane in your car versus race fuel. Both will run.....1 a little better than the other...depending on your definition of "better".

Run whatever is fresh and you can get a steady supply of. I personally run Torco 30% in my race rigs. Love the stuff..
 
Ok then. The "wear out a lot faster" response is pretty much what I expected to hear. Seems a little off to me that they would recommend a fuel that is going to kill their engines 50% quicker than the 20%.

---------- Post added at 10:56 AM ---------- Previous post was at 10:53 AM ----------

Wow don't know why that double posted. Thanks Moto.
 
MotoGod said:
In a nuthshell...the higher the nitro content...the cooler your engine will run. The lower the content the hotter it will run, but it will run longer (meaning say 10 min a tank versus 9 minutes). You won't damage your engine from running 30% over 20% unless it is shimmed incorrectly. It's like running 93 octane in your car versus race fuel. Both will run.....1 a little better than the other...depending on your definition of "better".

Run whatever is fresh and you can get a steady supply of. I personally run Torco 30% in my race rigs. Love the stuff..
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X2

Running 30% also requires a richer tune which will (as moto mentioned) run cooler, BUT it will also be running with more lube due to the richer mix. IMO 30% is easier to tune, runs cooler, has more lube and will make more power then 20%. 30% nitro isn't that high when you consider that some boat engines can run 65% without issue.
 
If... Your engine is not a premature detonator. Which the TRX 3.3 is. This causes pits on the piston and damages the glow plug. I've seen it damage the TRX 3.3. Maybe you could shim the head and change detonation timing. Then you'll possibly get better engine life. Not arguing... Definately agree that you can get cooler temps. if tuned properly, especially in airplane and boat applications. Just sharing my experiences with a specific engine. And, you guys brought some great info. to us.
 
Extreme RC Mods said:
X2

Running 30% also requires a richer tune which will (as moto mentioned) run cooler, BUT it will also be running with more lube due to the richer mix. IMO 30% is easier to tune, runs cooler, has more lube and will make more power then 20%. 30% nitro isn't that high when you consider that some boat engines can run 65% without issue.
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Cool thanks man (and moto). I have about 3/4 of a gallon of 20% to burn and then I think I'll try some 30% out.

---------- Post added at 12:50 PM ---------- Previous post was at 12:32 PM ----------
Smokin' Joe said:
If... Your engine is not a premature detonator. Which the TRX 3.3 is. This causes pits on the piston and damages the glow plug. I've seen it damage the TRX 3.3. Maybe you could shim the head and change detonation timing. Then you'll possibly get better engine life. Not arguing... Definately agree that you can get cooler temps. if tuned properly, especially in airplane and boat applications. Just sharing my experiences with a specific engine. And, you guys brought some great info. to us.
Click to expand...

Ok so (bear with me I'm new to this game) you have had personal experience running that % through that engine knowing that everything on the motor (tuning etc) was good to go? I know you said your friend had issues, and I have no idea of your experience level which is why I ask. Not trying to insult your intelligence I'm just trying to increase my knowledge.
 
From what I have read on the Traxxas forums and stuff...the TRX 3.3 can run 33% nitro with the factory shims. Anything higher would need additional shims, but plug heat range and tune has a LOT to do with that as well. I tend to run a hot plug (OS P3) in my engines with 30% Nitro. I could get away with a colder plug, but my tuning window seems to get much much smaller. I would say that I am an OK tuner. I can get my stuff to run and stay running....maybe not at 100% power....but 90% is good enough for me at this point in my RC career. haha

I have a new mod engine that I need to break in though...and the modder recommended a slightly colder plug (P4) due to the increased RPM range this sucker will have....so we shall see what happens I suppose.
 
I understand. They are right... Higher nitro means you run richer so you'll deliver more fuel and lube. I think it has a lot to do with head shims. If not shimmed enough, which I think is the problem with the 3.3, then higher Nitro fuel detonates too early and this damages the piston and breaks the engine down really quickly. He bought the SCT and the engine was gone a couple weeks later. Replaced it again in that same time period so he went to our local track and got advice from the coordinator/owner. Put a new engine in and ran 20% and it's still going. That is why I thought you may be able to shim the head and be OK. Not that you will not be anyways, just telling you what I've seen. Traxxas says use 20%. But, when it comes down to it, you do want the 30% if you can get it tuned and your detonation timing is OK. And, I will say I am not a Traxxas guy, but my racing partner swears by them.
 
my friend has only ran 30% nitro in his jato all the time and he has really good luck with it.. the only thing I know he had done was he got a bigger carb and drilled out the end of his exhaust alittlebit ( for more air flow) and that thing screams!!! I was running my jato on 20% and you definetly saw the difference.
 

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