Technical New owner with modified 650cc

[Sprockett]

I'm the new owner of a 1970 Fiat 500. I was told the engine is a 650cc that has been further enlarged. It's clear at least that it is making far more power than the original motor fitted to these cars.

So I'm looking to recondition the car to be in excellent mechanical shape. The front of the car is original except for the disc brake conversion and should be easy to order parts for. The rest of the car is a bit of a mystery to me however. I'm hoping some people here might be able to help identify what I have and what I might need to order.

First issues with the car are steering play related but I think that's all relatively straight forward.

There is also a good clunk due to drivetrain slop that I believe I tracked down to the outer axle on the left side. The axle turns a good bit before the wheel begins to move while the passenger side is tight. Not sure what this points to? Is there just the splines from the axle into the hub here or is there some kind of joint? I'm not sure however what axles would be fitted to the car to replace? I understand it's unlikely the original axles given the rest of the drivetrain? The car also has different rear drums as the bolt pattern is 4x98.

Another thing is perished bushes. I can't seem to find a part listing for the ones I'll Picture below. The appear to be the transmission mount? I can't find a part listing that looks like it though.

 

[Sprockett]

Here is a pic of the engine bay



Here is a pic of the drivers axle. I might also mention that these must not be the original rear drums as the car is runner 4x98 wheels.



This is the right side bushing I was describing. Picture is from the back looking forward. On the other side of the bushing is the cradle and front of the transmission.



Also, the flywheel cover is missing...this pic was taken after emptying two bottles of brake clean in the area.



Is this the correct flywheel cover?

http://m.ebay.com/itm/221750506851

 

[AndrewHarvey]

your engine is fitted with an after market D'ellorto FZD carburettor which is a desirable item - and best for a fast road engine.
I have not seen a transmission support like that...mine is like the attached.


All the suspension bushes are looking a little tired - not a huge job to change.


The drive shafts are normally uprated to 24mm dia - and the ali/rubber coupling to the stub axle is a known weakness - and can be uprated to a tripod CV joint for £150

 

[fiat500]

Gearbox mountings are Fiat 126 BIS.
.

 

[AndrewHarvey]

Are they an improvement over the item I fitted pictured above?

 

[fiat500]

Are they an improvement over the item I fitted pictured above?

I can't see any photo Andrew.
I doubt that the BIS rubbers are an improvement, especially when the engine output has been increased, because when I used to drive a BIS they seemed to flex a lot and regularly destoyed themselves, even though I had replaced them with new, Fiat parts.
I suppose that in theory they should work well as Fiat must have factored-in the increased power output of the BIS 704cc engine.
I am surprised that there isn't a modification for the gearbox mounting available involving urethane bobbins or silentbloc-type bushes. "back in the day" I had no end of trouble with them; but I've not yet had a problem with my current car.

 

[Sprockett]

Thanks for the replies! They are very very helpful.

Gearbox mountings are Fiat 126 BIS.
.

Ah great...to replace what I have I found these thanks to your description.

I have not seen a transmission support like that...mine is like the attached.

I'm open to changing or improving anything. Not sure how the item you pictured works? Do you have a picture of it in place?

The drive shafts are normally uprated to 24mm dia - and the ali/rubber coupling to the stub axle is a known weakness - and can be uprated to a tripod CV joint for £150

Thanks! So then this is the item that has failed?

Could you point me to a upgraded CV?

 

[AndrewHarvey]

eBay number 112156351787 for the CV joints
The standard gearbox cross member has two holes in it. The bracket shown bolts through them and a new hole you drill into the floor in the internal inspection hatch and bolt through - it stops the power train twisting.
I am also fitting a damper between the top of the cylinder head and the bodywork to stabilise the power unit

 

[timgarman]

What's the metal strip below the air vent at the back? That's not on my 1966 Bambina.

 

[Bambino]

I think that belongs on the sunroof.

Chris

 

[fiat500]

What's the metal strip below the air vent at the back? That's not on my 1966 Bambina.

Isn't that the handbrake cable?

 

[timgarman]

Peter – not what I was looking at.
Chris – you could be right. It's been adjusted to fit there though.

Phew – thought it was another part I might have to order.

 

[fiat500]

Peter – not what I was looking at.
Chris – you could be right. It's been adjusted to fit there though.

Phew – thought it was another part I might have to order.

I think we must get different photos up here on the top side of the Globe.: I still can't see it!

 

[the hobbler]

Peter;
If you look at the picture of the full view of the engine compartment you will see that there is apparently a strip of metal with raised bits through which the retaining screws for the air vent (under the rear window) go through. Normally there is no additional strip--it is the way that the light (camera flash?) has caught it which makes it look a different colour and therefore a separate 'strip'.

 

[fiat500]

I do see what you mean now Tom.
But I think you're saying (as I also think) that there's nothing unusual there. The apparent "strip" is normal (on an F or L anyway), and the indents are the slots to let rainwater out.
Attached the only photo I can find without going out to the garage.
JAN_1924-001 by Peter Thompson, on Flickr

 

[Vitesse]

I must admit I looked at that picture a number of times and couldn't see anything unusual. I think it must be our Antipodean cousins are seeing something we can't see, maybe the light is different down under?

Here is mine which is slightly different as it has the extra line indentation on the screw line that seemed to disappear on later model.

 

[timgarman]

Ok folks, I've had another look with my glasses on and (as Tom points out) it is the light catching that strip under the vent. It looked to me like a separate piece had been added.

Should I start a separate thread about this?

 

[Vitesse]

Yes! Call it "Blind ex-pat needs glasses advice"?

 

[fiat500]

More of the same. Only very slightly off-topic.

http://www.huffingtonpost.co.uk/ent...b8e4b01265268260d5?ncid=fcbklnkukhpmg00000001

 

[Vitesse]

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