Tuning Engine upgrade options 500D

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Tuning Engine upgrade options 500D

Bikesandcars

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I'm looking for an engine upgrade for my 500D as I get it on the road. I'm not building a race car but would like better acceleration. The old engine is tired. The car is OK overall, needs some minor fixes and it will be back on the road.

I see Mr Fiat has a variety of swaps. From 34 hp to 60. I'd like sporty but drivable. I don't know them. Im familiar with 40/80 cams on the x1/9 I used to have.

Can anyone comment on Mr.Fiats offerings or share some specs on what they have done or recommend?

Intended use is local occasional commutes, fun drives and a car show a year
 
I'm looking for an engine upgrade for my 500D as I get it on the road. I'm not building a race car but would like better acceleration. The old engine is tired. The car is OK overall, needs some minor fixes and it will be back on the road.

I see Mr Fiat has a variety of swaps. From 34 hp to 60. I'd like sporty but drivable. I don't know them. Im familiar with 40/80 cams on the x1/9 I used to have.

Can anyone comment on Mr.Fiats offerings or share some specs on what they have done or recommend?

Intended use is local occasional commutes, fun drives and a car show a year
The drive-train of the 500D is not really designed for between 2 and 3 times the original power output. My experience of an engine supplied by "Mr Fiat" could do nothing but tell you to stay well away from their engines. A relatively easy 'enhancement' would be to fit a set of "540cc" barrels and pistons, along with a 'warmer' camshaft (35/75/75/35), porting and skimming the head, with inlet valves 2mm bigger (at 34mm) than standard, stronger valve springs, and possibly slightly bigger carb (28IMB). This way it would look standard but you would get a noticeable improvement on performance without (a) straining the transmission and, (b) without straining the pocket. Doing the above would involve very little machining (the 540cc barrels are a straight swap with the original), but a bit of time and effort (which if you do yourself is free). The only time you would need to visit a machine shop is to have the head skimmed(40th: 1mm) and bigger inlet-valve seats fitted.
 
Thank you very much. I'm a somewhat experienced mechanic but new to the 500 games so this is exactly the kind of advice I need
 
There is virtually a large amount of tuning options for these cars. But im assuming your in the US?. Sourcing and hunting down the good parts is a bit of a task. Do you have a budget/performance gain in mind?

Performance upgrades is a common need for many of us in North America, with our relaitvely faster road traffic and longer straight roads, a stock 500 can be a bit of a scary experience at times.

Theres alot of good knowledge here if your looking for a place to start and planning your upgrades. the hobbler is one of them (y)
 
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A relatively easy 'enhancement' would be to fit a set of "540cc" barrels and pistons, along with a 'warmer' camshaft (35/75/75/35), porting and skimming the head, with inlet valves 2mm bigger (at 34mm) than standard, stronger valve springs, and possibly slightly bigger carb (28IMB). This way it would look standard but you would get a noticeable improvement on performance without (a) straining the transmission and, (b) without straining the pocket.


I hope this isn’t too much of a hi-jack of the original posters question, but I’ve seen you reccomend the same tuning combination to other members, and it sounds like a nicely matched set of upgrades that should work nicely together.

May I ask, do you know what kind of power an engine built to those specs will put out? I’ve seen you also suggest an aftermarket exhaust to complement those mods, is it also necessary to make any modifications to the air filter / intake? I notice the holes that feed the air to the filter on the stock 500 set-up are very small!!
 
There is virtually a large amount of tuning options for these cars. But im assuming your in the US?. Sourcing and hunting down the good parts is a bit of a task. Do you have a budget/performance gain in mind?

Performance upgrades is a common need for many of us in North America, with our relaitvely faster road traffic and longer straight roads, a stock 500 can be a bit of a scary experience at times.

Theres alot of good knowledge here if your looking for a place to start and planning your upgrades. the hobbler is one of them (y)
Thank you Jacques---definitely earned yourself a beer when we meet up!
 
The only problem about going fast in a 500 is what happens when you hit something that is stationary....
1650398587259.png
 
The only problem about going fast in a 500 is what happens when you hit something that is stationary....
View attachment 404943
I think the decision is to drive a Fiat 500 on the roads or not. Just like to drive a motorcycle or not. There are infinite ways for you to get crushed in a tin can including getting run over by a truck because you can't accelerate fast enough. Certainly don't want to dig up that topic. Heading to roll cage and a whole bunch of other equipment wasn't in my plan for the moment.

I would just like some usable power so I can drive the car occasionally and enjoy it
 
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I think the decision is to drive a Fiat 500 on the roads or not. Just like to drive a motorcycle or not. There are infinite ways for you to get crushed in a tin can including getting run over by a truck because you can't accelerate fast enough. Certainly don't want to dig up that topic. Heading to roll cage and a whole bunch of other equipment wasn't in my plan for the moment.

I would just like some usable power so I can drive the car occasionally and enjoy it
The 'enhancements' that I have suggested will give you probably just a bit more power than a standard '594' engine---much depends on (a) how much work you do on the head (porting, skimming, bigger inlet valves) and the carb that you fit (some of the versions of the 28IMB had a 23mm choke). By keeping to the IMB carb the engine will look very 'stock'---but the performance won't be! It is also fairly simple, inexpensive work that won't uprate the performance to the point that you have to start 'enhancing' other facets of the car. You don't buy a 500 to go fast---you buy it to put a grin on your face and **** off the Ferrari and Lamborghini owners at shows, because you will have the bigger crowd around you talking about their own history with a 'Cinquecento'. If you want to nkow more about tuning the 500 engine, drop me a line ([email protected]) and I will pass on my thoughts on the tuning of the 500 engine.
 
I agree the basic power can be dangerous.. 12bhp at new for a N is certainly not enough...
I have seen how many people look at a 500 trundling along compared to much more exotic cars...
I believe you should not buy a 500 if you don't want to talk to people....

I am all for giving them a little more pep but......
 
The 540 conversion is based on the fact that that is the biggest bore that can safely fit the standard 499 cc crankcase. The kit comes complete with high compression pistons so head skimming will not be necessary. The cylinder head can be much improved as mentioned including the inlet port which is only 26mm diameter. Opened up to 30mm in line with the 126 helps when fitting a 126 carb and spacer. Camshaft and improved exhaust also help and give the engine more pep.
Question is will it be enough for what you want.
 
The 540 conversion is based on the fact that that is the biggest bore that can safely fit the standard 499 cc crankcase. The kit comes complete with high compression pistons so head skimming will not be necessary. The cylinder head can be much improved as mentioned including the inlet port which is only 26mm diameter. Opened up to 30mm in line with the 126 helps when fitting a 126 carb and spacer. Camshaft and improved exhaust also help and give the engine more pep.
Question is will it be enough for what you want.
Whilst I totally respect your experience with the 500/126 engines and cars David, the 110 crankcase can be safely opened up to accept the 652cc barrels--BUT NO LARGER. But I do agree that for a variety of reasons, including load on the transmission and the fact that you are basically dealing with a 60 year old engine, the 540cc barrels/piston upgrade is as large as one should sensibly go with the 500D engine. One of my regular jobs at Radbourne Racing was upgrading the engines (for probably 500 'F' models) to 652cc, but as far as I can remember, I only converted NEW engines, although other mechanics may have upgraded customers existing cars.
 
Whilst I totally respect your experience with the 500/126 engines and cars David, the 110 crankcase can be safely opened up to accept the 652cc barrels--BUT NO LARGER. But I do agree that for a variety of reasons, including load on the transmission and the fact that you are basically dealing with a 60 year old engine, the 540cc barrels/piston upgrade is as large as one should sensibly go with the 500D engine. One of my regular jobs at Radbourne Racing was upgrading the engines (for probably 500 'F' models) to 652cc, but as far as I can remember, I only converted NEW engines, although other mechanics may have upgraded customers existing cars.
The car I have is complete and original. It needs some paint and a lot of the wear items are shot and I've started fixing them. Things like brakes and tie rod ends and tires etc. Instead of spending a lot of money modifying the existing engine why don't I keep that original in just take it out and swap in a 600 engine and running gear? Money is always an object because I'm just a standard working guy, who doesn't like to save money, but I'm also getting too old to futz around and I'd rather just get it running and enjoy it. I'm not trying to make a motorcycle engine conversion or a race car or anything I just want a nice driver that looks mostly stock, or if not stock maybe some mild abarth stuff
 
The car I have is complete and original. It needs some paint and a lot of the wear items are shot and I've started fixing them. Things like brakes and tie rod ends and tires etc. Instead of spending a lot of money modifying the existing engine why don't I keep that original in just take it out and swap in a 600 engine and running gear? Money is always an object because I'm just a standard working guy, who doesn't like to save money, but I'm also getting too old to futz around and I'd rather just get it running and enjoy it. I'm not trying to make a motorcycle engine conversion or a race car or anything I just want a nice driver that looks mostly stock, or if not stock maybe some mild abarth stuff
A stock '594' engine would be a sensible alternative to a 'warmed-up' 540cc engine. But, be aware, you will have to also change the gearbox bell-housing, the starter (still 'lever-pull') and possibly clutch (to a later '126' type) and release bearing- Nothing is simple! The '126' style starter has a support bracket and flywheel 'shield' that will also require to be acquired. If it will help you, let me know who you are planning to buy your parts from and I willlist out the parts/part-numbers for you. I do realise that you are in America, but you might find that one of the European suppliers might,in the long run, be cheaper than "Mr Fiat"
 
Well you answered the two main questions that were in my mind ie the money pot is not endless and that you can do some work yourself. If you are going for a 594 then favourite for you would be to look out for a Fiat 500R engine and gearbox and switch to a 126 carb. This would solve your problem, including the necessary drive shaft up upgrade and give you the performance of at least a 126 in standard form. You being in the US makes this much harder and I think you need to keep an eye out to see what is about or pops up.
 
Funny thing....
many years ago my brother won a weekend rally course with Rothmans...
the oldies will remember Ari Aatanen he did the track training and the Ford mechanics gave a run though on how to build a rally car....
the funnist question at the start was "How do you make a car go faster?"
What did every one answer Head? Cam? carbs, exhaust?

The answer was BRAKES!
 
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