205 SR project thread

[kupakcorp 0]

I am starting this topic to get your help and knowledge, and also to document my adventure with my 205.

 

Stock setup: 

1990 205 SR, TU3A, aircon. 1 barrel Solex carb, 68 HP.

 

As it stands now: 

-Engine is badly knocking (still runs, but the last trip will be to the mechanic who changes the engine)

 

My plan, imagine it as Stage 1:
-I can get a blacktop 90HP VTR engine. I want to use it as the lower end of the build. (NFZ engine code)

-Head will be a TU3S head off of an AX GT, and the the Solex Z2 carb too. Yes, I am aware that this is a small valve setup, but it is very simple.

-Gearbox will remain the MA5 that is currently in the car.

-Ignition will be managed by a Nodiz Pro setup, as I think this project clearly requires ditching the distributor.

-I will install a wideband sensor to be able to set the carb up properly.

-Target hp: 95

 

 

My question:

-Does the MA5 gearbox bolts up to the Saxo blacktop engine? In the pictures it seems like the casting is different behind the flywheel on the block.

-Headgasket from TU5 or TU3? MLS type?

 

If the NFZ is not the best choice for that setup what other 1,6 PSA engine is a straight fit? (The 1.6 bottom end from the 206 looks very similar to the Tu3 I have).

 

Ps. the car leaped into project car territory, so I will keep the original 1.6 head, in case it is time to upgrade

[calvinhorse 870]

You will need the 1.6 head gasket and 1.6 timing belt

 

the Saxo lower radiator hose can be cut down to fit your radiator 

 

the gearbox will fit but your flywheel will will not be covered underneath, I’ve been running mine like this for years and it has caused no problems 

 

[calvinhorse 870]

I think the black top engine has slightly dished pistons

 

the silver top has flat top pistons, I used one of these with a Tu3s and the compression is very high, you’d need good quality high octane fuel.

[kupakcorp 0]

Thank you! 

 

I will be running it with fuel with a minimum 98 RON (EVO 100 on the pump), fortunately fuel quality is pretty good here.

 

[kupakcorp 0]

Update time!

 

My 205 SR has an aluminium block, so I ditched the TU5 bottom end idea. It has enough understeer as is, and going down the route of adding more weight and trying to compensate with suspension is a very long and windy road that I have seen many people struggle with.

 

New plan: block remains, but I already scored a TU3S cylinder head, with the twin choke Solex, and the manifold. It needs a rebuild and a heavy skim, but I am happy.  Suspension will be overhauled too, and I plan on fitting GTI shocks front and back. If it upsets the handling it is easy to revert to stock at least

 

Target BHP remains 95, and I still plan to use high octane fuel. I hope that I can get a pretty aggresive ignition curve with the Nodiz, and can dial in the carb with the help of the wideband O2 sensor.

 

I will also get a vernier pulley, to combat the timing retardation because of the heavy head skim (it has never been skimmed, but there is corrosion). I think 1mm skim should give me a good surface. 

 

Also the 205 in question is with aircon, and I don't want to get rid of it, as it seems very rare. The carb change should make this a nice challenge, because of the Auto-gas feature when you press the A/C button. 

 

With the help of a friend we started to disassemble the car, there are gunk and rusted bolts everywhere on the exterior, as expected

[camgti 56]

Great project. The base model cars are good fun. 
 

Fit a gri rear arb to the rear will help with understeer. Find and fit rear gti bars if you can slo as that will help. The have a lovely ride and soft front spring. A little stiffer in the rear is what you want. You can fit gti dampers and springs also. 
 

If you go to the trouble (which its worth imo) fit the front subframe from gti while the engine is out. Its all straight forward and will be the cheapest easiest setup to make it handle well. 

[kupakcorp 0]

Update time.

 

Managed to score an engine + box from a 106 S1 Rallye  This changed the plan a bit, as I want to build a carbed car  while I can. Ignition only ECU is already in place, so it will be a bike carb conversion, because buying twin Webers cost the same here as a full kit from DanST, shipped. 

 

Also got the calipers from the 106, which are nice lightweight Bendix ones (According to my measurements, they are the same as the Bendixes on the SR, only the brake pad carrier are different - to accommodate the air cooled discs).

 

Upgrading to a GTI subframe is on the table, only need the luck to find one. But after finding that complete Rallye engine only 75 miles away I think luck is on this projects side.