Fiat 127 MK2 | timamotorsport

Exterior

- Special mirrors - are beautiful, that's all.

- Lightweight Rims - Lighter rims always improve performance and handling. I think the rims are quite rare and look like fanalone style

- Bonnet Air Intake - No impact on performance, but gives an aggressive appearance.

Mechanically

Finally, I made some change mechanically. After a lot of research, I decided to invest in a preparation that would be similar to the Ceccato Preparation, very popular during the 70's for the 903cc engine.

However I decided not to do an exact replica since some parts are already very rare, and because they often become less adequate for a modern use, such as an even shorter differential which would make highway travelling unbearable and the car would travel barely at 90km/h comfortably.

Estimated power with this preparation - 80HP

- Fully Engine Repair – Engine block rectification, new pistons and everything that was needed. I always believe that before start tuning the engine it is important to restore lost power.

- FACET electric Fuel Pump- Any increase in performance would mean that the engine would use more fuel. The OEM fuel pump would not be able to provide enough flow, so I decided to install an electric pump.

- Abarth Camshaft – This engine definitely needs to breath better and the Abarth camshaft is a great help in this part. I know I would lose the bottom-end torque but I think is a good compromise. The camshaft HP peak should be around 6.400RPM with torque peak at 4.000RPM. Some sources indicate higher numbers on peak RPM at 7.000 RPM and torque peak 4.500 RPM, not big difference, but still noticiable.

- Distribution Triger Kit - does not increase HP, but the engine RPM would increase faster as the chain is lighter and causes less attriction..

- Intake manifold - A "big smile" intake manifold from a specialized shop. It was not cheap but will improve the intake massively and resolve the intake bottleneck. The original small window need to feed all 4 cylinders at low and high RPM which is impossible. The wider intake will allow the air and the fuel to flow faster, with better throttle response all around the power curve.

- Carb - With an improved intake manifold I believe I can gain some extra HP by changing carb. I think I will choose a Weber DCD 28/36 it can give some extra fuel specially once the second barrel opens, but will not hurt the bottom end with excess fuel like other more aggressive carbs.

- Exhaust Manifold 4-2-1- After improving the intake it is necessary to improve the exhaust. A 4-2-1 system from the Abarth A112 is enough for a highly tuned 1050cc, so it works perfecly for a 903cc.

- Exhaust muffler – Muffler change will not significantly increase power, top 1-2HP, but an exhaust system without restriction is important, and gives a more appropriate soundtrack to the car.

- New Shock Absorbers, lowering springs and tires - This is only connection to the ground, an important part often ignored. So I bought everything new and the combination is very good, the car has a good amount of grip, despite the problem of weight distribution (too much weight in the forward axle allow the rear axle to sometimes behave like a rear wheel drive car).

- New Braking System – If the car accelerates faster it needs to brake harder. I did not upgrade anything, but changed everything for quality OEM parts and that should be enough. If not, will upgrade to racing pads, but for a daily driver is not recommended.

Outcome

After everything done with the help of a specialist shop and a huge bill to pay on all this "upgrades", I went to the road to test it. The car is clearly faster, revs easily to in 2nd gear to 7.000RPM even when the car is in a steep hill, something that previously was impossible. The third gear is still very useless. When changing from 2nd to 3rd the RPM band drops significantly and the car have troubles to accelerate when in a steep hill. Yet, better than previously when the car would actually lose power constantly until I had to change to 2nd again. On a straight road the car revs easily in any gear and is accelerating much faster than before. Clearly a good upgrade for serious performance.

I reckon that the car currently is around 75hp (real ones, not like the 70hp people claim on Abarth kit that are around 55hp-60hp), which is very good for a Natural Aspired car with a 903cc engine. I think I reached the maximum that this engine has to give without jeopardizing reliability

ed the maximum that this engine has to give without jepordizing reliability.

The car is now ready and no more upgrades are planned. Only normaly maintenance and replacing parts as issues come along.

Car evolution and upgrading details

Introduction

I few years ago when I decided that I would fulfil a childhood dream of buying a classic car I started to look around for the best option. After a lot of research I finally settled on a car: a Fiat 127 MK2. What makes the small 70's car ideal as a first classic you may ask?

- First, because not only is it cheaper to buy a Fiat 127 compared with Ford Escort’s, Alfa Romeo’s, Fiat 124 Spider’s or even Datsun 1200, Corolla 1200 but also because it is easier to maintain since Fiat's spare parts for this car are very easy to come across in Portugal compared with other classic cars.

- Second, and this is already personal opinion, the car has a unique style! Not a show-off car, but everywhere I go with it, my Fiat 127 is always the centre of attention, which in a classic car is something that you want!

- Third, it is as simple as a car can get, not complicated systems, and for a person like me that is starting to restore and prepare a car for the first time, it is an important feature.

So I gained courage, took a deep breath and a finally bought a Fiat 127 for myself. The car already add some work done on it, but it was still far from being the car of my dreams. Therefore I started to plan the car I wanted. I had to decide which kind of restoration wanted to do:

1 - Restore the car to its original state, with some customization as if I had picked the car from factory.

2 - Make a personalized car with some sporty extras to make it unique and fun to own.

3 - Restore the car to its original look, make minor mechanical changes to give some extra HP and a very careful maintenance to ensure reliability.

4 – Transform a simple day to day car from the 70’s into a rally car, with all security, appearance and mechanical preparation needed in such a machine.

After investigating about the car I decided to go for the last option, and create a fully prepared car. I started to think about an engine swap. Several option came to mind that wouldn't need major changes and could be easily applied, the more extreme would be the Fiat 1600 SOHC from Lancia Delta or a Fiat Uno Turbo engine. In the end I decided that I would stay with the stock engine. I knew since the beginning it wouldn't be a fast car, but I would improve it as much as possible. In the end, a classic car is not about speed, but driving sensation, and I was sure that it could put a smile on my face.

Following the advice of most experts, set the budget first and then start the restoration and looking for parts.

Final cost of the rebuild&preparation of the car: 6058€ in parts and specialized work ( but excluding all the weekends I spent taking out all mechanical parts to paint the car, mouting all the new material like shoch absorbers and Springs. I have a team of mechanics that do some small things for free when it becomes too much for my knowledge).

Car Specifications

Interior

- Weight reduction – Take-out from the interior everything that is not necessary. Best performance with zero investment, the dream of anyone tuning a car. Also, sound proofing material is highly flamable, something to avoid in a rally car.

- Tachometer (rev counter)- the first change I did to the car. It will not make the car go faster, but it looks good and helps me use the engine more efficently.

- Circuit Breaker - Important if there is a problem and have to turn off everything in the car. It was installed by a professional, electrics are not my expertise.

- Seats + Competition Belts - Safety and lumbar support allows for greater comfort when going to the limit.

- Fire Extinguisher – Regulatory Requirement to participate on Regularity Rallies, definitely a necessary investment.

- Roll-Cage - Safety above all, the car can go to the scrapyard, but not me! Painted yellow because it looked aggressive but I think I will take it out and paint it black. Someone already gave me the paint, now only need the time to take the roll bar out, paint it and put it back.

- Abarth Steering Wheel - Original steering wheels of the Fiat 127 MK2 are clearly made for a relaxed driving, an Abarth Steering wheel is a great upgrade. I bought one that needed to be repaired but was usable, I will repair it when I have time and money.

- Intercoms - An absolute must when you spend a lof of time in the car.

- Rally style gear knob – No performance gain or extra security but in my opinion looks very good.

March 2015

When I bought the car the car came with a 32DMTR and Abarth Valve Cover. The first thing I did was to enlarge the intake as much as possible with that valve cover. But it was very restrictive in the end so I decided to invest in better material.

I took some picturesto describe the changes. Below a more detailed explanation

The intake port was enlarged as much as possible, with the limitation being the Abarth intake manifold that was enlarged to the reasonable limit. So first I enlarged the intake as much as possible and then matched the cylinder head intake port. The image shows how the intake looks after enlargement.

Abarth Camshaft, directly from Italy with the 219 code from the 70HP Abarth engine. I am not an expert but I think it has longer duration and higher lift (280º vs 244º lift I do not know) allowing for the engine to breath better.

A Weber 32DMTR carb was my choice due to the wide availability of such an option in Portugal. The valve cover obliges to change the carb to a Weber DMTR. I tried to find a 34DMTR but nothing, so I had to settle for a 32 DMTR.

April 2016

I order an upgrade intake manifold. The shipping was fast and once I had the intake manifold with me and the cylinder head was port & polished, it was time to put all the pieces together, something I was eager to do after so much work. With the 28/36DCD carburettor and an experienced mechanic next to me, it was the perfect opportunity to do things right. The description of all the work is detailed below. Finally the head is ready to be installed in the engine. Now I only need the time to put it back and see if I can fine tune the engine with the new carb. It will not be an easy task, but I will do it with a mechanic that works with my dad and he is an expert on this kind of work, a lot of experience.

Since I had the intake manifold with me, I decided that instead of spending hours with my machine (Dremel/Driller) trying to open up the intake port , it was better to send the cylinder head and the intake manifold to a workshop that could open the port to match the manifold and save me hours of work.

The final result was still very rough and a lot of work was still ahead of me to make it just perfect.

My first step was to build the intake manifold gasket that would be used as a model to open up every possible inch in the cylinder head. Only like this I could make a perfect match between the cylinder head and the intake manifold and avoid unnecessary turbulence that would reduce performance.

Once I started to work on the cylinder head, I notice that it was very rough around the hedges, as the machine does a vertical cut when opening the intake port. After the machine opened the intake it created a 90º turn between the cylinder head and the intake channel, and the sharp hedge would create unnecessary turbulence in the air flow. In order to reduce turbulence, using a finger and a sanding paper I made a smooth transaction that would guide the air to the intake ports.

After a lot of hours in the workshop to make it right, the picture shows the final outcome. I am pretty happy with it and looking forward to see it in action.

After all the work I described below I turned the valves to make sure they are sitting right in the valves seats and assembled the valves springs and everything.

olts.

Just for comparison, I have an extra cylinder head that I kept just in case I would need another one if something went wrong.

I took a picture of the original one compared with mine just to see the difference in the intake shape. The new one is much larger than the old one which will allow air to flow much better to the intake valves.

I did not want to do much on the intake ports. From what I know it is important to leave a rough surface on the intake ports to make a good mixture between air and fuel.

So on the intake I decided not to polish anything, just around the valve guides to make it smoother, but did not reduce its length, I was advised not to do it as it could mess up with the valves functioning system, or even melt them.

The main work on the intake was around the C shaped entrance to cylinders 2 - 3. I decided to reduce the shape slightly using the casting mark that you can see there to guide me. That would be the limit on the amount of metal I could remove. It is not much, but for sure it will help to gain some HP. The pictures are too dark I know, but it was the best I could do with my mobile.

Regarding the exhaust, I did not do anything special again, I left the shape of the ports as they were. Changing the shape of the port is very tricky, and almost always it will flow worse than it did before.

In this engine the port clearly can be divided into 4 parts. The 1st part is the exhaust bowl, the part next to the valve and that has the valve guide in it, where the air just came out of the cylinder and will do the 90º degree turn to the exhaust port. The 2nd part is a wide port just after the air turned 90º to the port. This is a wide part that can flow a lot of air and will take care of the turbulence of the 90º turn. The 3rd part is a narrower part of the port. I am not an expert, but from my understanding the main objective is to increase air speed and therefore allow for a faster exit of the exhaust gases. The 4th and last part is the section of the head that will enlarge until it meets the manifold.

Below some explanation on what I did in the different sections:

1st section - the exhaust bowl was the section that took me longer, It is highly inefficient and could flow much better, After polishing the interior to remove all the small imperfections, I decided to smooth the exhaust guide. Removing some material from the sides of the guide will not only allow to flow more air, but also reduce turbulence and "guide" the exhaust gas to the port. After dealing with the guide, I improved the exit of the bowl to the port. There is a C shaped curve where the bowl and the port meet and where the exhaust gas needs to make the turn. I removed this C shape imperfection to allow the air to flow easier and use all the available section to do the turn.

2nd section - No need to do any changes here, it is already wide enough to flow properly and allow the exhaust gas to make the turn easily. I used a sand paper just to remove all the imperfections (started at 60 for a first approach, than 100, 240, 600 and 800) Everything was made by hand as the port is too small for a machine to do it)

3rd section - The narrow part is important to keep the air speed up. But it is made to flow on a normal engine with a 32 carburettor and a normal camshaft. But since I made some changes, mainly a 36DCD and the Abarth camshaft, the mechanic said that slightly opening that part would still keep a good air speed but would also improve the gas flow. But opening too much would make the wall too thin (the water jet would be too close to the port) and I could risk destroying the cylinder head and the engine. So, using the casting marks where I knew it had no water passages, I removed the excess material from there, did not go beyond that since there was no need, it already improved significantly vs the original (2-3 mm) and would be enough.

4th - Not much can be gained here besides polishing to the max (800 sand paper).

In the end, the exhaust was properly polished and smooth, the mechanic was impressed with the work and said that it can give some extra HP. Once everything is put together we will see if it can go faster.

May 2016

After all the work I described below I turned the valves to make sure they are sitting right in the valves seats and assembled the valves springs and everything.

Once I tried to put everything together, things were not as fast as I was hoping for. A lot of issues raised that required specialized help.

- The throttle linkage needed to be changed. The original one was not compatible with the new carb, so a new one had to be fabricated (which included welding the valve cover)

- The carb is just a few inches from the bonnet, so no air filter fits there. After searching a lot, a very high tech solution was found. I was going to bolt the filter right on in the carburettor. I will show a picture later on.

- This carb had no return tube like the DMTR carb. The car could work without it, but the gasoline pump was clearly working harder without the petrol return tube. The specialist did make one linked to a valve to open and close the return because he said the car had more torque with the return closed. I saw no difference in performance, so for now it is always open to avoid destroying the fuel pump.

- New and longer head bolts since the intake bolts-on in the head bolts.