Buying the right engine for your needs and budget
Words: Sylvain Lafrance
One day or another, you’ll have to buy a new engine. All the reasons are good to drop a new mill into our rides. Some wants to upgrade their RTR engines for a more powerfull engine, some others try to take advantage of a better fuel mileage and others want to replace a broken or worn out engine. Choosing the right engine for your budget might be more complicated that you might think. Just by surfing one of the most popular online store. I’ve seen more than 80 off-road .21 engines to choose from with a street price varying between 110$us and 600$us. This makes a lot of choices! So, how to choose the right engine?
What you must be looking for when buying a new engine?
First thing you should be looking at when buying a new engine is your budget. If you have 200$ to invest on a new engine, don’t spend 300$. Respect your budget. It is best to buy a 200$ engine and still have money left in your pockets to buy fuel rather than a 300$ engine and been broken for the rest of the season.
Don’t buy a used engine at the exception that you know extremely well the seller and what he has done with the engine. I have seen so many persons who have bought used engines and the engines were just good for the junk. Buy smaller or cheaper but buy new. If you plan to race, toward your search on engines that have a smooth power band, good fuel mileage and good support from the manufacturer. According to your budget, engines that are used by pro racers like the Novarossi 21 Plus 4 (300$us), the Reedy 121VR (250$us) and the OS Speed .21 VZ-VB V-Spec (540$us) must be considered.
Do you really need a high performance engine?
If you are a diehard racer, the answer is yes. Otherwise, of course you can buy an high priced high performance engine but there are chances you don’t need it. In fact, you can buy whatever engine you want, after all, we are living in a free world. But the facts are that you may not need high end engines for succeed. Engines with a larger number of ports usually produce more RPMs than engines with 3 or 4 ports. On another hand, engines with less ports produce more torque. The choice between such engines is a matter of likings and track configuration.
Which engine is the best?
This question comes often. What is the best engine for my buggy or for my truggy? The answer is extremely easy. The best engine you can drop into your ride is an engine that will not flame out, stall, overheat and will run tank after tank flawlessly. There is no specific brand or model to name here. If you take your time and pay close attention to break in, tune and maintain your engine, you will enjoy and have success with nitro engines. A well tuned 120$ engine is better than a 500$ engine poorly tuned that will flame out or overheat after few minutes of running.
When power is too much:
Yes, this is possible to have too much power and this is common to see racers using too much powerful engines or using too much power from their engines. Personally, I don’t like overpowered vehicles because of my driving skills and style. Too much power just makes my vehicles harder to control and cause extra wheels spinning. Having a little extra power to clear double jumps is correct but I don’t want more than that. Don’t buy your next engine by giving too much importance to the manufacturers’ specs. No manufacturer uses the same method to calculate or evaluate RPMs and HPs. Don’t base your decision on claimed HPs or RPMs.
If you ride a 2wd vehicle like a stadium truck. It is easy to have too much power. Those vehicles are extremely sensitive to power and their transmissions are prone to break more easily with high power and torque engines. Keep it simple and put chances on your side, run an engine with a little bit less power. The Dynamite .12SPD engine still a popular choice because of its ease of tuning and its performance that makes any stadium truck predictable and smooth to drive.
Stick to the rules:
If you plan to only run your vehicle in your backyard with friends and to not participate to any local races, you don’t have to worry about the size of the engine you’ll buy. However, if you plan to race at your local track, this is a totally different story. Race tracks apply engine rules and you must respect them. Rules slightly vary from track to track. It is a good idea to contact the folks at your race track to know what rules are applied. In a general rule of thumb, here are the rules relative to engine displacement for each popular class:
Nitro stadium truck: Only .12ci engines are allowed. At some race tracks, the stadium truck class is less popular and the track owners will let you race with any engine.
Monster truck (small block): Any engine with a displacement smaller than .21ci.
Monster truck (big block): All engines between .21ci and .28ci. Some tracks allow engines up to .32ci
1/8 buggy: Only .21ci engines are allowed in this class. Some race tracks have a “beginner” class where any engines can be raced. This class allows new comers to race their RTR vehicles and having fun together.
Truggy (1/8 truck): Engines with a displacement between .21ci and .28ci are allowed in this class. Just like the buggy class, many tracks will let newbies race in a “beginner” class without any rules concerning the engines, just for the fun to race.
Take care of your engine:
During the full life of your engine, you’ll have to take care of it. Engine maintenance begins with a proper breakin. It is very important to follow the manufacturer breakin procedure, this insures better engine performances, a longer lifespan and makes your engine easier to fine tune.
Clean and oil the inner and outer air filters frequently and use after run oil when you store the engine for more than a week. It is preferable to run your engine slightly on the rich side. This can save your engine during long races or under hard conditions like mud, worn out clutch or small air leaks. In case of problem when tuning your engine, always go back to the factory settings. Use a zip tie to secure the air filter to the carburetor.
What about RTR engines?
Today’s some Ready-To-Run vehicles come with engines delivering good power and being easy to tune. This is exactly the case with the Losi 8ight 2.0 RTR buggy. Losi has included the Losi 350, a race worthy and race legal .21 engine. RTR engines are known for being user friendly but they are also known for wearing out faster than high priced engines. A RTR engine can easily last six, seven or eight gallons before it dies. I have a RTR engine here on my shelf that has went through 11 gallons of fuel and it still running fine.
All engines are not made equally:
That’s right; you get what you pay for. A 110$ engine has definitively not the same engineering, performances and lifespan than a 600$ engine. Few years ago, major engines manufacturers were investing a lot of money into R&D to add every little HP’s and RPM’s they can into their engines. Today, engines manufacturers still invest their money to develop high performance engines but they are now more oriented on fuel mileage than never before.
High performance engines cost more and they are packed with features that increase their power, they have a better durability and they use better quality material. Many “hot” engines last more than 12 gallons before they need rebuild. Composite carburetors, turbo scoop crankshafts, ceramic bearings, high performance cooling heads, turbo glow plugs, smooth power band, increased fuel mileage and tighter pinch are all common features in today high performance engines. All those features explain why you see those engines particularly on race tracks and not in backyards. Their street prices begins somewhere in the 225$-250$us.
Less expensive engines have less “performance” features but this doesn’t mean they don’t worth the money you pay for. Some low-budget engines or “sports” engines are not just for the backyards, they perform well on race tracks too. The LRP .28 engine is a good example of an engine with good performance with a reasonable price tag.
Conclusion:No matter what stadium truck, buggy, truggy or monster truck that you ride, keep in mind that you have a budget limit and focus on what you really need. Yes, a 550$ will look really cool in your vehicle but if you can’t handle all the power it produces, it doesn’t worth more than a 200$ engine. Take your time, ask questions to your hobby shop and to experimented persons. Hope this article will help you to pick the right engine for your needs.