Page 6 of 6

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: May 8th, 2019, 8:13 pm
by Spider 1969
3 & 4 Relocating the firewall and brake pedal:

The postion where the steering shaft passes through the firewall needed to be relocated approximately 50 mm and 45 degrees down and right from the original postion. See below photo.

Also the brake pedal needed to be modified to clear the steering shaft.

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: May 8th, 2019, 8:26 pm
by Spider 1969
5 Modifying the steering rack location:

Last weekend after installing the suspension and steering components I wanted to pre align the hubs. I turned the steering wheel from full left to full right and count d3,5 turns. Then turned it back to 1,75 turns to the straight ahead postion (in theory). I the found out that the inner steering joint on the right is located 20 mm further out board than the one on the left. See below photo. Conclusion is that the steering rack is not centered and that this kind of misalignment of the inner steering joints will lead to bump steer.

I will remove the suspension and cross member to be able to relocate the left steering rack bracket 10 mm to the left and rectify the missalignment.

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: May 18th, 2019, 7:17 pm
by Spider 1969
5 Modifying the steering rack location continued:

I removed the cross member and removed the left side bracket as this one fixates the location of the steering rack. I the tack welded it 10 mm to the left from previous position and did some measurements that confirmed that the rack is centered. After final welding and paint it was simple bolting everything up again.

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: May 18th, 2019, 7:26 pm
by Spider 1969
6 Modification of the gear box cross member

As the sump was fouling the steering rack I had to shim the engine mounts to clear the sump. As a result the gearbox output flange was not parallel to the differential flange any more. (a difference of 0.4 degrees). I cut the gearbox cross member and welded the central part that contains the rubber mount in a higher position. After mock up, painting and bolting back again protractor measurements confirmed the right position. The prop shaft central bearing also was shimmed to compensate for the increased height until the front prop shaft was 90 degrees relative to the gearbox output flange.

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: May 20th, 2019, 1:47 pm
by Guy Croft
FANTASTIC COMMENTARY, DETAIL, INFORMATION AND PHOTOS!

GC

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: May 26th, 2019, 12:21 am
by Spider 1969
7: Modifying the throttle linkage

Due to discarding the original steering box it was necessary to fabricate an alternative throttle linkage. The original throttle linkage spindle had been located with the rear bushingin a bracket at the steering box and with the front bushing in a bracket on the IDF manifold (sorry no photo available).
So I made a bracket to accommodate both bushings on the inlet manifold. Also I to located this spindle 8 mm lower and 5 mm more towards the engine which as needed due to the increased engine mount height.

Now it is finally time to start doing what this modifications were needed for: Installing a new GC approved header and fabricating a 2,25" stainless steel exhaust system!

(Don't know why the photos are rotated; sorry for that!)

Re: 1969 Fiat 124 SpiderAS 1800 conversion

Posted: July 7th, 2019, 9:32 pm
by Spider 1969
Finally: exhaust time. Installed the GC design and GC approved MCJ Abarth header. Very happy that it actually fits because I had to install the rack and pinion steering to make it possible. Attached a home made exhaust to it consisting of 55 mm stainless steel pipe, bends and one muffler to it. Used two V-band couplings to facilitate fast and easy exhaust removal/installment when needed. Can't wait to hear its sound! Just some routine maintenance like a cam belt change, oil change etc. and it will be ready for start up and a shake out drive. After that: straight to an alignment shop.