Busi

Hello! I have been looking at getting a HPI Savage X 4.6.

But recently new EU laws have made so it consumers can longer buy nitro with more than 16%.
but how would that go in line with the F4.6 big block engine, i see that its generally recommended to run 20-25% but that is no longer as so an option here in EU

Would it be possible to get the HPI Savage X to run on 16% or would it be recommended to find something else. even that it seems most nitro cars sold in Denmark is being recommend 20-25%..

the options as so is HPI Bullet MT Or ST 3.0 and HPI Savage x 4.6

kawasaki161

Don't worry about it, it'll run fine, RTR engines can handle just about everything you throw at them. If it feels less powerful to you you could take out 0.1mm worth of head shims.

Roelof

It will run.....

The manual op the engine shows 2 shims: https://www.hpiracing.com/assets/doc...2-glb-m-v1.pdf

You can remove a shim of 0.1mm to make it work better with 16%

1995 Monster T

What you really need to be concerned about is the oil lube content. run 14% oil lube. All nitro does is give you power.

Roelof

When you give advise or such a statement then I think you do not understand the technology. Where does the power come from? Is it pure combustion power or is there more? I can tell you there is more, it is more about ignition timing. The Nitro content in combination with the compression are 2 main factors determining ignition timing.

1995 Monster T

A nitro engine will run on )% nitro The power comes from the combustion of nitro.. The more nitro the more power!

Roelof

Again, you think you know, I advise you to take a deep dive into the technology of these self ignition/combustion of these engines.

For a part, yes, you are right!
But the other part is the shifted ignition timing. If you lower the nitro content then yes, you will notice a drop in power but not only by a lower combustion power but also by a later ignition and with that a later combustion. By taking out a headshim you will bring back the ignition to a better moment and with that you will bing back a lot of combustion power.

1995 Monster T

NitroRC.com | Fuel Mixture Workshop Removing head shims is only necessary for low nitro content. Most engines use 1 head shim up to 20% nitro and 2 shims above nitro. So Yea I do get it! I don't run fuel above 20%.. More nitro more power. Plane and simple. I have been running nitro for 37 years now.

Roelof

So if some too simple information on a website tells the simple explanation of Nitro=power then go ahead if you want to believe that.
That you are running RC cars for 37 years does not prove you have an in depth knowledge.The same counts for your warnings about oil in 2 topics.

Also one shim used on most engines for a low nitro content and 2 for higher? Most of my engines have a stack of several sized shims just running 16%

Many people over here in Europe, especially the bashers with bigger engines are complaining their engines will not run on 16% (actual it needs to be 12% by volume by EU law) because manuals like the HPI F4.6 does not advise that. So far I have seen is that the LRP 32X manual says to remove a shim when running 16%. Funny thing is that the 1/8 onroad scene is allready running 16% for many years w/o any issues.

kgombe

iTrader: (13)

I like how people reference the number of head shims without taking into consideration the thickness of these head shims.. so just take out 1.. LOL


funny

Not directed at you Roelof

1995 Monster T

The link is plane and simple truth. Too bad you can't rrun more nitro. Here in the US there is no ban I can use what ever I want. I can even buy nitro anytime I want. Os has always recommended 18% lube in all the manual up to 2010 and Now Os doesn't recommend less as you say. Just Quality commercial fuel in all the current manuals. So run less oil. Your just burning up your engines faster.

Roelof

Indeed, the link is plain too simple, is the website in the link yours? You did mention it several times so it would not surprise me....
Again, it is wise to know more about the technology before you can be sure about your advise and knowledge.