Race Engine Forum UK

miro.
Can i ask where you got the aluminium strut bodies from. I have toyed with making some in the past. enjoying watching your progress.

sach.

I actually will use the original ones and will have these spare , so if you are interested I will be happy to part with them.

Miro

The remaining problem is the springs.

Does anybody have any idea of the following measurements of either stradale or corsa springs.
I still am looking for the pictures of rear turrets ( from the boot -or trunk- view).

I am not sure if both stradale and later corsa used looked the same. Current knowledge is that before spherical top mounts were introduced and original spherical top mount turret modification .omologated , the corsa ( and stradale) has unmodified rear turrets, unlike the picture below.
Miro

see also : viewtopic.php?f=14&t=2176

Miro, a very good job you made so far.
i'm learning from your experience here , so when you finish i will start converting mine too .

you know i have a BMW 520 model 1986 complete diff fitted in my Fiat 131 G4 replica , with some modifications like these. tha major problem was in the struts and springs ( the same that you are facing right now ) , but i didnt change anything in the body of my car , i modified everything else that if some day i will fit the original axle , it will remain original without notecing anychange.

keep up the excellent work , and hope to see it on the street again soon.

Major breakthrough re: Abarth suspension

Finally we are on the right track thanks to a Belgian friend Geert, who provided data on the springs and spherical top mountings.

The missing spring data was:

HEIGHT OF SPRING UNCOMPRESSED 415 MM
INTERNAL DIAMETER 102 MM
COILS REAR /FRONT 9
SPRING DIAMETER 12.4 MM


There remains still one catch .

These are springs for 131 Abarth but it is not clear if this Applies to Stradale or Corsa or both, but this should be resolved quickly.

Also tip mounts for the struts in an Abarth issue seems to be clarified:

According to available pictures Stradale front mountings were not the standard 131 parts. Available Stradale pictures indicate that both Stradale and Corsa had spherical top mounts on the front.

The difference on the front between Stradale and Corsa seems to be that on a Stradale the top mounts were installed with minor modification ( a collar to fit the spherical top mounts has been added to replace the standard opening for the standard top mount.


On a Corsa - major modification extra space was added by welling hub on top of the turret.
As far as the rear is concerned i still am not totally sure but what appears to be the case is that both Stradale and Corsa used spherical bearing top mounts on the rear as well.

Corsa rear top turrets were heavily modifies (extended) so that their top was higher than the rear window shelf.
If pictures from Geert show a Stradale rear turret it looks like the rear Stradale turrets were also modified ( as compared to standard 131) , but modification was smaller than in case of a Corsa version. Still some space has been added (at an angle) to the top of the turret.

Miro

Hi Miro,
Might I inquire what your fuel system is? Looks to be a fully mechanical system and I am looking for a similer type for a special application.

Thanks
Robert

Kugelfischer, as BMW 2002 injection (2002Ti ?)

GC

Thanks Guy.

If not mistaken, is that a slide throttle system?

it is, yes

G

NEW FRONT BRAKES.

They will be fitted with 285mm disks.
Size is right except they will not fir in a 13" rim.
This is why I am getting 7 x15" CD 68 replicas
Miro




Miro

Re: Top struts mount :

The problem appears to be bigger than originally anticipated.

The rear top strut mounts in Stradale are still unknown.

Conflicting information are inconclusive . On one hand the pictures I received indicate that rear top strut mounts in Stradale were based on spherical bearings, on the other all pictures of the struts indicate that the top mount was atualy the same as in the front of Mk2.

We have tried to do it this was without modifying the turret except for removing the bolts on top. Did not work. The opening is 65 mm and the opening required by the front top mounts is 80mm.


Thus we have decided to built out own top mounts based on spherical bearing. Initially it will a standard bearing , but we have already ordered Moto Sports version. We will build (manufacture) a two piece housing for the bearing one being a circular part holding the bearing from the bottom and a hat shape "cap" of matching dimensions to hold the bearing on the top. The bearing will be mounted on the strut and held by a nut. Our top mount will be installed from the bottom of the turret and bolted to the top of the turret using the oles left after removing original bolts.
The bearing selected has a working angle of 17degrees which should be plenty to accommodate the strut side movements under road conditions. The bearing is a FLURO GE20FO -2RS it has a static load of 240kN (24 tons) , a dynamic load of 48 kN ( 4.8 tons) and a pivoting angle of 17degrees. This should suffice


Miro

As normal the top of the strut where the bearing was to be mounted proved to be slightly oversize ( 20.35 mm) and the bearing opening was slightly undersize (19,89 mm) so we had to machine both top struts to proper opening. As always Mr Jan proved to be a master of his trade.

Top mounts.

After seeing all I could and researching the subject very deeply I decided it was time to come up with a simple and working resolution of the problem.

I have designed the spherical top mounts myself :

Here they are :

Top part :
Bottom part
and a spherical bearing in between .
This nicely creates a sandwich that goes on top of the strut and under the existing top of the rear turret.

The working angle of the bearing is 17 deg. The angle of the top of the turret in standard 131 is 4 deg. In total the working angle is from -13 deg to plus 21 deg. By my calculation this should be well over the required range to accommodate the strut tilt due to to wheel moving up and down (as limited by the arm and the strut).
We will probably make first trial installation of the strut and spring assembly tomorrow. It it looks ok we will attach the strut to the hub and see it this looks OK. Next stop will be to attach the strut to the hub put the wheel on and try to estimate the sideways movement of the strut , due t the wheel moving up and down on a bumpy road. And finally we will try to see if we can test this movement the due to body tilt on a sharp curve.



I am keeping my fingers crossed that it works.

However we have a "plan B" putting a steel wedge between the top mount and the top of the turret to which it is bolted. If push comes to shove this should give us sufficient additional tilting angle. Car body tilt on the curve will be the key to controlling angle of the strut to the body. Another extra measure we will pursue if required is a shock travel limiter like they did on the original.

Tomorrow should be a test show if this works as good in real life as it looks on paper.


Miro

Hi Miro,
Good luck with the project, ive been following it from your 1st post. Seems like its coming along nice.
Can i ask where are you getting the 15x7 CD68 replicas? Im looking for some new wheels for my AC coupe :-)

HEY ,


And contact Jonathan Sege at : jssage@hotmail.com

At my encouragement Jonathan has arranged with Compomotive to make 72 such wheels ( 2 will be cut up for stress resting so there will be 70 available. The wheels have been cast already and during the next two weeks will undergo heat treatment, machining and powder coating. They will be shipping in about 15-20 days I know there is a long list of people who have already ordered the wheels so I am not sure how many are left , but do try.

Otherwise there are no 15x7 CD68 replicas available. All advertising by others like ruota market was just story as they never produced a single piece.