Automotive Dynamometer Systems(dynamo meter/rolling soad) information

Once you have built your new motor, or fitted any tuning parts you will NEED to visit a good automotive Dynamometer or rolling road. If you don't you will never be able to set up your engine properly. A good dynamometer allows you to use a gas analyser while under load so you can see the real air fuel mixture at all RPM's while driving.

Rather than discuss the subject on this site it is better if you go to my Automotive Dynamometer pages, as I used to build them! (Below)

Chip tuning, or chipping your car...

Non Turbo Cars

Heard a boy racer telling his mate the other day "just fitted a chip to my xxxxx car (non turbo) yesterday, and its loads faster!". Well that is just NOT possible.

I asked him how and he didn't know, but said it was about 20mph faster flat out! Now since it takes 4x the power to go twice as fast, that equates to a simply huge power increase! So he was obviously lying...

First of all, a noticeable increase in power is simply not possible with a naturally aspirated car (no turbo) by fitting a "chip" or having it "chipped". As we said in the first few pages engines breath air. If you do not increase this flow somehow it cannot make more power than it already is doing! That chip simply tells the fuel system how much is the CORRECT amount of fuel to add! The manufacturers stock settings are usually optimum for peak power. It also controls the Ignition timing, but again the stock settings will be about perfect for full power. It is only possible to get tiny gains in "drivability" rather than more real power.

t is possible to gain a few percent here and there at different rpm's and throttle plate positions, because the manufacturers tailor the fuel map to give optimum economy, smoothness and low emissions. But these gains are pretty small. They "may" result in better drivability, but definitely not enough extra power to notice!

Turbo Cars

It is possible however to chip a turbo car for more power in many cases. The max boost level is often controlled by the engine management system. So in this case reprogramming, or rather remapping the ECU or chip can bring power increases. Be careful though because the manufacturers set these things as they are often for good reasons - usually reliability!

By allowing the turbo to make higher boost the engine gets more air and therefore can make more power, often considerably more.

Conventional Engine tuning methods

By "conventional engine tuning" we mean internal engine work. Not Turbocharging, Supercharging, Nitrous Oxide Injection, etc. No "bolt on power" modifications. but tuning the internals to give better airflow.

Getting more power from a standard car engine by conventional tuning means is at best difficult. (we will ignore standard turbocharged cars for the moment). The only way is to increase the airflow drawn through the engine. There are lots of ways to do this and it all involves a lot of work and money! For example:

• Bigger side draft carbs or throttle bodies

• Bigger engine bores / pistons (machined to increase capacity)

• Bigger engine stroke (offset ground machined crankpins and shorter connecting rods)

• better tubular exhaust manifolds and system

• better port shape in the head (ported head)

• Bigger inlet and exhaust valves fitted with specially shaped valve seats

• Higher compression ratio

• longer duration and higher lift camshaft

• forged pistons (for strength)

• stronger connecting rods to cope with higher RPM's

• uprated oil pump/system to help engine reliability at higher RPM's

• Crank / Connecting rod lightening, balancing, strengthening etc to cope with higher RPM's than standard engine

Depending on what you are trying to achieve you may need to do all of the above or just some! A fully tuned and "built" race engine is seriously expensive, loud, and unsuitable for road car use. It has bad driving characteristics, uneven idle, little low rpm power etc. And it is usually short lived as it has to be revved hard to get to any useful power. Obviously then it is best to start with the biggest engine variant of your model of car to begin with! This way you may not need to tune it at all to get the same power! If you do tune it it will not need as extensive modification to achieve the desired power so will be more user friendly.

Conventional tuning has low limits on how much power you can expect too. Its easy to get a few horsepower more, but very difficult to get any big power increases. And the cost of power goes up and up as more power is wanted...

Unless you have a good reason to use "conventional tuning" rather than fitting a bigger engine, or a turbocharger or Nitrous injection then these are probably better options for road use.

Tuning and LPG or Propane alternative fuel vehicles

The short answer here is that LPG or Propane fuel has a higher detonation limit so makes a better fuel for tuning than pump petroleum does.

It allows either more turbo boost, or higher compression ratios, or more nitrous to be used before detonation of fuel stops play!

In short, if you want power its a great idea!

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