ACTUAL PERFORMANCES

  Last updated on 30th May 2001.

   As you may know, sometimes real world performances are not close to the official ones. Let's see some facts.

If you know about more information that could help me to complete this section, please feel free to contact me.

Actual Figures

    I've chosen  to compare standard EVO I & EVO 16V Cat to : 
a)  former Integrale 8V ,
b)  their first contender : Escort Cosworth
c)  the latest  Japanese Cars : Mitsubishi Lancer Evo V and
d)  Subaru Impreza 99 model.

First fact to see is Last Integrale EVO is significantly slower than all other cars including 1987 8 valve model. There are two reasons for this : (1) The higher weight of the car; (2) Smaller turbo which leads to enhanced driveability but prevents good results in high rpm range.

Figures for the Escort Cosworth are from first produced cars ( with big turbo unit (T35)). Figures better than integrales are obtained in acceleration, but the car is almost undriveable in normal conditons due to high turbo lag.

We can get more knowledge if we take a look at power & torque Graphs.

Power Graphs

First we are comparing Delta Evoluzione I to Delta Evoluzione Cat and to Delta Integrale 8V.

Due to smaller turbo, Evo Cat has more power in low rpm and turbo starts up at 2500 rpm, but on the other side engine almost "dies" at 5000 rpm and only delivers 200 bhp (compared with claimed 215). For first Evoluzione, power goes up at higher revs, and from 4000 rpm there is more power. That's why we have better figures in acceleration, as we use always the high rpm band. Evo Cat maximum speed is seriously conditioned by lack of power at higher rpm. Integrale 8V can beat Evo Cat in acceleration due to almost the same top power (7% less) but with less weight (10% less). The 16 valve camhead for earlier 16V and EVO I has added more power at higher rpm compared to 8V in expense of low rpm driving ability.

Now we can compare Evoluzione I to some of the newer Japanese Cars : Subaru Impreza  and top performers Mitsubishi Lancer and Subaru STI :

It can be noticed that below 4000 rpm there are no significant differences between them and our Integrale. Note: they are not running higher boost, but mantain it steady through all the rpm band, providing higher Bhp figures at higher rpm. Japanese cars have engines with smaller stroke distance which favours power at high rpm compared with our Italian long stroke motors (bore smaller than stroke) favouring low rpm torque in expense of high band output. However,  main difference is that Japanese cars mantain turbo boost at higher rpm, while our Integrale drops to 0.6 bar from previous max 1 bar. So, if we get the boost mantained at high rpm, we can almost get up to their power figures.

Next Graph compares an Standard Evoluzione I using 3 different brand Chips :

1) an OE Chip ;

 2) a Chip from Arese in Netherlands +31(0)20-497781. Not a very hard performer, this chip only raises slightly boost (from 1 to 1.1bar) but mantains it up to higher rpms (0.9 bar at 6000 rpm)::

 3) Evocars Hybrid Chip. From Evocars in U.K. (http://www.evocars.com). That's the one I'm using in my car, and I'm very happy with it. Maximum boost is about 1.35bar dropping to 0.9 bar at 6000 rpm.

These figures are with OE Airfilter and Exhaust system. (Only chip replacement).

You almost get  the same power just to 3000 rpm, from that point higher boost leads to more power in mid and high rpm band, with engine over 200bhp until 7000 rpm, with a flat power band. By now, I don't have figures for Superchips or Abarth chips in order to compare their results.

Torque Graphs

Looking at this graph you can see the fact that japanese motors mantain boost at higher rpm.

The main difference for Arese and Evocars Chips is slightly higher boost mantained at higher rpm, with ignition and fuel supplied remaped, so torque curve looks more like a Japanese car.

Gear Shift Points

We are going to take a look at when we should shift gears in order to achieve maximum power at the wheels (that's to say maximum acceleration). Every engine/gearbox combination have their optimum shift points. Shift must be made when power at wheels at selected gear is the same than at next gear (making equal wheel torque before and after the shift) . So it will be at higher rpm than maximum power output. Please keep in mind that a different final drive ratio or tire size will shift the curves in horizontal axis (shift point speed will be different), but the optimum shift point RPM will remain the same.

First graph is for Standard EVO I with standard Gearbox and Wheels/Tyres (205/50ZR15) :

We can observe that standard Gearbox is quite short geared as maximum speed is obtained past maximum power rpm. We can increase gearing by fitting big wheel/tyres up to 7%, but then all gears will shift up in speed by this percentage.

This gearing allows around 200 bhp be used from 100 Km/h to 220 Km/h, but in first two shifts output falls to about 180 bhp.

In order to arrange this, we can choose some diferent gear ratios. Although somewhat expensive two different gearearkits with 5-speed can be found :

Each of them can be obtained in 4 different final drive ratios i.e. 13x57, 14x57, 15x56 or 16x55.

I've choosed the first one with a 16x55 final ratio, as I found it's the only suitable if you are not going to use the car only for rallying. Taking in mind our standard engine "dies" at 6000 rpm, it's useful to extend our gearing by further fitting big wheel/tyre combinations : what about a 235/40ZR17? (6,71% more gearing). You can take a look to what the shift points will be now :

We have now 200 bhp from just 55 Km/h, a slightly longer first gear, second gear with almost same gearing, and the last 3 gears being much shorter. I guess maximum speed will be somewhat around 200 Km/h.

If we tune our car with Evocars Hybrid ECU (255 Bhp), as it delivers more power at higher rpm band, the gear optimum shift points with OE gearbox and wheel/tyre are :

Gear shifts with stock gearbox must be made at higher rpm in shorter gears and occur at higher speeds. There are more problems with first and second shifts because we are shifting near red line (7000rpm) with a huge power fall. Maximum speed of 233 Km/h can be expected (a real benefit).

Now we are going to fit the above mentioned Close Ratio Gearbox in a Evocars tuned engine, and switching to a larger diameter wheel :

This gearbox is more suitable for the tuned engine than it was for the stock one. 225Bhp from 50 Km/h. With a top speed of about 215Km/h (although about 6800rpm). Gear shifts happen near to stock combination's speeds (except for the first one) but at higher rpm. Some drawbacks : a longer 1st gear (more clutch use at starts) and in 2nd gear less accelerating force than stock (we'll see that later.)

Further improvement : Evocars tuned engine with stock gearbox and 15x56 final drive ratio fitted. (a cheaper option than buying a full gearbox, only about 1/4 of total amount). I would prefer 16x55, which would give more top speed, but it's not available as a spare part. Now the shift points happen close to those of stock gearbox (with Evocars chip), but down the Km/h range, obtaining almost the same shift point's speed as with Stock engine/gearbox and almost the same top Speed.

Choosing Gear Ratios

    Power vs. Speed graphs give a good idea about best shift points, but we can go further and make some new graphs. I've choosed Accel. vs Speed. First if we know the torque an engine is developing at an amount rpm, knowing the gear ratio and final ratios, and wheel/tyre diameter and transmission losses, we can obtain how many force the wheels apply on the ground. This is the acceleration force. First three variables are easy to know, but transmission losses arenīt, so I estimated them to be about 20% of force developed (that's the usual figure in AWD vehicles, falling to 15% in 2WD ones usually). Force equals mass by acceleration, as we know car's mass is not changing while we accelerate we can make the graph like acceleration vs Speed. I donīt fancy Acceleration figures in m/s^2 so I've decided to show them in G's (dividing them by 9.81). Car is stopped by aerodynamical and frictional losses. Aerodynamical force is proportional to the square of speed and front surface, the factor of proportionality is named Cx coefficient, so itīs somewhat easy to calculate. Drawing graphs with acceleration in G's leads to choose a cars mass, I've choosed for all of them 1350 Kg. A 10% increase in mass would show a 10% decrease in G's.

 Our first graph compares Stock Evo I vs. Evocars chipped using a closer ratio gearbox and big wheel/tyres :

First fact : Top speed is obtained where aerodynamics cross our accelerating force, i.e. 222 for stock & 220 for Evocars CRG. Gear shift points are located where  the accelerating force in one gear equals to that force  in next gear's. More aceleration is obtained  in Stock combination just to 37 Km/h (blue curves) but from there Evocars CRG is better. Red 5th gear gives the same or better acceleration than Stock 4th one. There are big improvements in 45-80 Km/h range (but in 1st gear) and 50-160Km/h (in 2nd,3rd & 4th). Drawbacks : not higher top speed (I don't mind about that) and longer first and second gears. Car is slower in 2nd just to 50 Km/h, which for me is a big drawback (I'm not inclined to shift to 1st gear in each tight corner on open roads), and most of all, high clutch wear from standing starts (longer 1st). After all, this combination can deliver amusement over roads were usual speed is between 60 and 180 Km/h.

Finished building page at this point

Acceleration & Distance Graphs

Final Results

These are the final results of all that stuff :

Speed and Distances were calculated from the previous graphs but considering a gear shift time of 0.30 seconds. This affects to some extent distance graphs,  about 4% at 1000 meter line (about 1,5% more time spent), but time to get a speed is also affected. (About 0.9 seconds from 0 to 140 Km/h), also you'll notice speed at a given distance is significantly slower than the one shown by the graphs i.e. minus 7Km/h at 1000 meter standing start. So :