So I need an uprated spring for my 66 Giardiniera. I got one but its too small of a diameter. So there is a 500R 126 spring and a N/D/F/L spring that I ordered. Can I assume the 500R spring would be a bigger diameter?

The Giardiniera engine rear-mounting spring is unique to the Giardy---look on the "Passione 500" web-site. On the 'engine parts' section you will find that they sell the spring you require---part number:--MOT223

Is it really unique? The diameter of the R spring isnt similar? Also that mot223 is a stock spring, I need a stiff spring, the stock one does not cut it in this application

It is unusual for the Giardy to be tuned, and therefore require a stronger than standard spring--result, there is not enough market to justify somebody making them for such small demand. The only sensible suggestion that I can therefore make is for you to take the 'standard' Giardy rear engine-mount spring to a company that can make springs, and ask them to supply one to the same DIMENSIONS bur with a greater spring RATE.

Would a spring from a Fiat 600 or 850 fit? These have 4 cyl. engines, therefore heavier. www.fiatplus.com list them for the 850 incl. part no's.

If you shorten a coil spring by e.g cutting one coil off, this stiffens it. You can make up a spacer to restore the lost height. Or do like on engine valve springs and fit another spring inside the original?

There used to 'coil spring assisters' available to boost sagging springs or to use when towing. Maybe you could fabricate something similar on a smaller scale to fit inside the engine support spring. These assisters often look like shaped rubber sections that are fitted in between the coils with the spring extended - then when a load is applied both the spring and the rubber liners has to be compressed - this is harder than just compressing the spring.

Iirc, you converted this vehicle to electric power - do you still need the 'engine' mounting to be capable of accomodating rocking motion? Maybe fitting just one standard engine mounting from e.g. the 124 Spider would do the job? The Fiat 850 engine mounting top casting had a mounting for an engine steady bar - just in case you decide to fit one.

AL.

Well since this is electric im not worried about vibration, I think im going to put a longer spacer in there to limit movement. My issue is on heave accel it just compresses the spring completely and the the transaxle starts to move up and twists, then I end up with binding axles. If I just limit the movement to maybe 1/2 inch i think it will be fine. Thanks for the info guys!

Mark

In the light of your comments re.torque from engine and vibration (or lack of), try looking at the problem from a different angle---have a look at the rear engine mount from a Hillman Imp---might just do the job.

Ahh, that would help limiting up and down movement, but twisting would be an issue then. Watching the drivertrain when loaded down, the motor drops, the transaxle goes up and twists with the torque, the trans mounts arnt exactly very firm, even new...at the moment I have the trans out to reseal it, so when Ill see what happens by limiting the drop when i put it back together.

If torque-twist is your main problem,I would suggest that just fitting a stronger rear-mount spring is not the answer. If you have a look at some of the u-tube films regarding the building and tuning of "Classic Abarth 695" engines you will be (a) amazed at some of the ingenuity/engineering and, (b) some of the rear-mounts built for these engines might be your answer. Some of them do away completely with the Fiat system and have built (for want of a better description) 'plate' mounts, where a plate is bolted to the engine and sits on another plate (on the test-bed frame) with big 'bobbin' rubbers restricting the movement, in between the plates.

Got the car back together and up after limiting the rear spring movement to under 1/2 inch and it still does it. Put the car up on a 4 post and torqued the motor, and yeah, its tearing the new transmission mounts already and the top cover on the trans is slapping the floor. Its moving a lot! I did a utube search and did not really see what you were talking about. I definitely need some ideas for limiting torque twist, its really bad.

For the "plate" type mount that I was talking about, look at the u-tube film:---
"classic Fiat 500 Abarth, won a classic rally at nurbergring, germany" (note slightly different spelling of the Nurburgring). I think an adaption of this type of mount might solve your 'torque-twist' problem. There are also a number of 'u-tube' films of 'electrified' Cinquecentos, and some of them have details of the companies involved.

I think we have a solution, removed the spring completely and used some rubber isolators. No reason really to have the spring in there with this setup. Also gonna add a second mount across from that, same basic setup. The way the motor is in there it wont be hard to fab something up.

Problem solved, removed the original spring and used some cushy rubber isolators, and made a second mount using similar rubber isolators on the other side of the motor, mounted to the rear like the original engine mount bracket. Super slight amount of vibration added, but not enough to even consider and it hardly moves now, no more torque twist, no more issues with axle binding or the trans-axle hitting the floor.

Media is starting to get done on the car so as soon as something posts Ill throw it up in the top level of the 500 classic forum.