RcTek : Information & Resources for the Model Car Racer

Frequently Asked Questions - Engines

Below we have Frequently Asked Questions (FAQ) about the engines used in R/C model cars & trucks.

The majority of these questions and answers relate to large scale engine tuning, although many of them are applicable to engines from other scales.

Related articles and content may be found in the index to this section.

My Dealer Sells Torx™ Type Engine Mounting Screws. Do I Need Them?

Whilst the greater tool contact area gives the ability to tighten the screws further, you can tighten them sufficiently using an Allen type screws. Many people try to use an Allen key that is worn and consequently irreparably damage the top of the screw. Allen keys can be either be re-ground or inexpensively replaced. The Torx™ Screws are more expensive and require the added outlay for a tool that will not normally be used for anything else. See the Fixings & Fasteners section for further details.

Submitted by: The webmaster.

How Much Power Will I Have Once You’ve Tuned My Engine?

This depends on what you mean by power. The peak power achieved is not as important as the overall spread of power across the entire rev range. It is quite easy to modify an engine and get 5 or 6 horsepower, but it is also very easy to have an unusable engine because there is no power low down in the revs. An engine that produces a spread of power across the entire usable rev range (6,000 to 20,000 or more) will be quicker on the track with 4 to 4.5 bhp, than an engine with 5 to 6 bhp which only produces the power high up in the rev range. Further information regarding Model Car Engines

Submitted by: Ian Oddie.

Do You Think The Car Will Handle The Extra Power?

If the car is in reasonable condition then there shouldn’t be any problems. Remember though, that with more power the car is under more stress and parts will wear out faster, especially the drive train (gears, drive shafts and drive cups).

Submitted by: Ian Oddie.

Do I Need An Adjustable Clutch?

An adjustable clutch is beneficial even on a standard engine. This is because they allow the engine to reach higher revs before engaging, hopefully where the engine has started to produce more power (approx 7000rpm).

Submitted by: Ian Oddie.

How Quickly Will The Engine Wear Out?

A modified engine will wear out faster than a standard engine, because of the increased stress and rpm reached. The piston ring is probably the part that wears out first and then the bearings and seals. Change ring around every 6 hours of running time and the bearings and seals at 10-12 hours (second ring change). Although the changing the ring is fairly straightforward, we can change the bearings and seals at a competitive price for you if required. Further information regarding Model Car Engines

Submitted by: Ian Oddie.

Will I Destroy Tyres Faster Because Of The Extra Power?

Tyres are obviously going to be under more load, but as long as you choose the correct compound you won’t have a problem. Tyre wear is affected by driving style, track temperature, and how fast you’re driving more than anything else.

Submitted by: Ian Oddie.

Will The Engine Use More Fuel?

Many things affect fuel consumption. You would assume that a modified (faster) engine would use more fuel, but they can in fact be more economical .The reason for this is because with more power you will not have the throttle open as long between corners (you should get there faster). If an engine has been modified and is significantly worse on fuel consumption than it was before, the alterations that have been made are not working efficiently and are wasting fuel. Further information regarding Model Car Engines

Submitted by: Ian Oddie.

Why Is One Car Faster Than Another With The Same Tuned Engine?

Taking actual driving ability out of the equation, there are a few reasons for this;

  1. Each engine arrives as is from the factory, there are no “blueprinted” versions available. Whilst we strive to modify every engine to achieve its maximum potential, some engines are simply better than others (the parts fit better, giving more efficient flow characteristics).
  2. Different manufacturers cars are constructed in different ways, some are more efficient than others. How well set-up and maintained is your car? Do you check it during/after every meeting? The most significant gain you can probably make is to make sure that all parts are free running and not binding in any way. Even if you had the most powerful engine in the world, you would be wasting your time if it couldn’t be efficiently transferred into moving the car forward.

Further information regarding Model Car Engines

Submitted by: Ian Oddie.

How Do I Clean My Air Filter?

The air filter should ideally be cleaned from the inside out, as any cleaning operation should not push any dust, etc.. into a position where it can enter the engine. An airline can be used to blow the majority of the dust away and then fuel or a suitable solvent used to rinse out the remainder. The filter should then be allowed to dry before applying a small quantity of air filter oil. This applies to foam type filters, paper types should be replaced.

Submitted by: The webmaster.

How Do I Set The Carburettor On My Zenoah G2D 23cc Engine?

The mixture screws should be turned fully in (not tightly) and adjusted as follows;

Top - Marked T (Shaped like a T-Bar) = 1 1/8 (1.125) of a turn out.

Bottom - Marked L (Slotted Screw) = 1 1/4 (1.25) of a turn out.

Turn the idle screw all the way in to just fully compress the spring and then back 2.5 turns. Further information regarding Zenoah Engines

Submitted by: Rob Lochier.

We have expanded this information into an article about Large Scale Engine Settings

How Do I Set The Carburettor On My Solo 23cc Engine?

For Samba 2, First One pipes,and the Lauterbacher 4 chamber. The bottom end screw (marked “L”) should be 1 & 1/4 turns out. The top end screw (marked “H”) should be 1 & 3/4 turns out. The tick over speed screw should be approx 3 turns out.

For most other pipes The bottom end screw (marked “L”) should be 1 turn out. The top end screw (marked “H”) should be 1 & 3/4 turns out. The tick over speed screw should be about 4 or 5 turns out.

From these points the engine should only need fine adjustments for optimum performance.

Submitted by: Ian Oddie.

We have expanded this information into an article about Large Scale Engine Settings

My Engine Tuner Says His Dyno Is Accurate. Is This True?

Every Dyno (Dynamometer) is slightly different. Different construction methods, running conditions, etc.. alter the characteristics of a dyno. What a well constructed and maintained dyno offers is repeatable results relative to all the others it has produced. So, for example, if a Dyno A gave a 2% reading difference from Dyno B, its results would still tell you that an engine gave 10% more power in its modified state than in its unmodified state. Further information regarding Model Car Engines

Submitted by: The webmaster.

The Standard Zenoah Engine in my SVM car is overheating?

Although there are a few causes for overheating such as incorrect fuel/oil mixtures, a problem I have encountered was tracked down to the standard air filter. Although the foam looked clean, there is a fine gauze under the foam that easily becomes blocked with fine dust. It was suggested that the gauze be cut away, but that seriously reduces the effectiveness of the air filter. The solution to this problem is to oil the filter as it does not come pre-oiled, and clean it regularly.

Submitted by: The webmaster.

Further Information

If you did not find the answer to any question you may have, please feel free to ask them on our On-line Forum.

Home : Top

© 2001, 2009 by Darren Burnhill