Fiat 850 Coupe 1967(1000OT)

[Hermanzini]

If you look at my Coupe VIN tag below, the paint code can be seen at the very bottom of the alloy tag. My car had paint code #233 (Bianco/White) as original on both the body & the roof.

My tag is missing the paint code numbers.... It stops with the partsnumber.

 

[Hermanzini]

The replica front grille, side badges & rear lettering are all good steps in creating a good-looking tribute car as you're doing. Even better when these items are applied correctly on a car as beautiful & well-kept as yours is. But seeing as how the 850-based Abarth cars never had any type of Abarth ID tags on them, installing a fake tag will only make the car look foolish (my :2c. Why cheapen all the hard work you've done to make your car look good & look (reasonably) like an OTS by installing an obviously-fake & inappropriate tag like this? :confuse2:

"Disguising" your 1050 engine just a bit more using a few Fiat 850 bits would help to give it an older "period" look, as well. I see you have a block-off plate where the 1050 fuel pump would normally be mounted, so I'm guessing you'll be using an electric fuel pump? If so, swapping your 1050 timing chain cover with a regular Fiat 850 one would get rid of that big ugly fuel pump mount bulge at the front/left corner of your engine.

Removing the coolant tube from the front/right corner of the cylinder head (above the generator mounting studs) & plugging the hole with a hex plug (or welding-up the hole) would also help get rid of (or at least reduce) things that would normally be out of place on an OTS engine.

With just these 2 minor modifications, your 36DCD/manifold & OT1000 sump (& maybe a nice exhaust/header system) in place & no inappropriate badges/emblems/tags in sight, a quick glance into your engine bay would have things looking fairly appropriate for an OTS or OTSS tribute car (the only obviously-noticeable difference being the oil filter on the side of the engine).

Do you also have an "OTS" rear script? (they're elusive)

Hi Jeff!

Thanks for the good tips!

Do you know if the colorcode could be stamped somwhere else? I have seen more tags like mine without the paintcodes on them.

OT script will do, looks better too IMH!+ I can not get my hands on one anyway!

Powerwise it will be in OTR/1324 territory, from the front it looks like a 1324, from the sides it could be OT/OTR/OTS and from the rear it looks like an OT.
It is already a "bastard", but in a good way.

I just want a nice looking, good working classic car!
The s1 coupe is already one of the nicest designs i know, with these Abarth upgrades it will have the power to match its looks!

 

[johnt]

Interesting differences between the OTS,1300 and Radially that I never considered. I would think all the radiator grills were the same for the coupe other than the 2000.
Grill size/dimensions, Grill opening cut in front, Radiator size, ducting in the trunk and maybe other items that are different.
I wonder why Abarth engineers chose different grill treatments.
Was it due to the size of the radiator? Was the sheetmetal opening cut differently between the OTS and 1300 since they had different grills?

 

[Hermanzini]

Interesting differences between the OTS,1300 and Radially that I never considered. I would think all the radiator grills were the same for the coupe other than the 2000.
Grill size/dimensions, Grill opening cut in front, Radiator size, ducting in the trunk and maybe other items that are different.
I wonder why Abarth engineers chose different grill treatments.
Was it due to the size of the radiator? Was the sheetmetal opening cut differently between the OTS and 1300 since they had different grills?

Yes it was different cutouts, the 1300 was wider and deeper than the 1000's. They also used different sizes radiators, the OTR also had an oilcooler in the front behind the radiator. Not sure if the OTS had that?

All I need now is to find a suitable radiator to put in there....

 

[johnt]

Yes it was different cutouts, the 1300 was wider and deeper than the 1000's. They also used different sizes radiators, the OTR also had an oilcooler in the front behind the radiator. Not sure if the OTS had that?

All I need now is to find a suitable radiator to put in there....

I think I need a grill too :love::love::love:
Wonder where I can get an OTS size grill :huh:
Maybe I have to make one one

 

[Hermanzini]

I think I need a grill too :love::love::love:
Wonder where I can get an OTS size grill :huh:
Maybe I have to make one one

Berni Motori has one or two original grilles, but I dare not Ask the price.....
I have not found OTS/OTR replica grilles, but GMR might have one more s1 1300/124 grille and maybe 2 s2 1300/124 grilles..
To get the GMR s1 grille to fit, you have to cut out the ribs and make cuts on the sides to match the bodyshape.
You also have to bend and stretch it in every way to make it fit(ish)
Then you must cut the script to fit the new shape of the grille....:mallet:
It is a lot of work, but it pays off in the end.

 

[Hermanzini]

If you look at my Coupe VIN tag below, the paint code can be seen at the very bottom of the alloy tag. My car had paint code #233 (Bianco/White) as original on both the body & the roof.

The colorcode on my car is 491 azzurro, original color looks like it was 583 beige sabbia.
If you look through the grille you can see the original color on the two vertical "beams".
I did not find any colorcodes yet.

 

[Hermanzini]

The price for an original OT steeringwheel is way out of my pricerange, so I made a tribute of my own.

 

[jvandyke]

amazing!
That is going to really confuse somebody some day! You should sign the back!

 

[Hermanzini]

Thanks!

I have found a perfect radiator to put in there, its from a MK1 Ford Fiesta.
The outlets are also in the same place as the Abarth radiator, so that is a bonus.

 

[Hermanzini]

The radiator is in place, i will make a shroud out of aluminium.
The engine and rear radiator is now removed from the car, the original color was indeed gray/beige.

 

[Hermanzini]

I am almost finished with the radiatorshroud, I made out of aluminium.
The batteryboxfasteners and the bolts for the luggagelid holds it in place.







I also cut a hole in the firewall for the plumbing to the front radiator, trying to match the hole i have Seen on OTR/S.



The oilsump was also bolted in place today.

 

[kmead]

Great job. Really coming together nicely.

Thank you very much for documenting this build.

 

[Hermanzini]

Thanks, Karl!

Today I started to bend and route the waterpipes for the front radiator.
I will have a problem going under the front stabilizer bar, it is not enough space.....
Did Abarth just knock on the floor with a hammer until it was enough space for the pipes....? :hammer:

 

[Hermanzini]

The plumbing is finished and the new Abarth 1050 engine is mounted in the car. The exhaust is also new, Abarth replica.
Tomorrow I will try to fire up the beast.... Fingers crossed!

 

[Hermanzini]

I got the car running and it sounds glorious!:love:
it is idling very rough though.
It also went out of breath on higher revs on the road, so I opened the carb (DCD 28/36)to see what was inside.
The first thing I found was that the emulsion tubes had changed place, so the bigger one sat on the smaller side of the carburetor.
When I changed this the car would rev up the range, but still it will not idle and when warm it hesitates when you blip the accelerator.
Also the idle mix screw has no effect, only when bottomed out.(stops the engine)

The jetting is:

Starter air jet 150
Main jets 125/125
Idle jets 50/70
Emulsion tubes 200/220
Chokes are 24

Engine is Abarth 1050 ccm 70 Hp.

Does anyone have an idea if the jetting is way off or in the "ballpark"
Maybe the main jets also should be different sizes...?

Thanks!

 

[Hermanzini]

I have ordered 45 idle jets, they ones I have may be too big.
Very little info on jetting online, had hoped to get some good input from you guys.

I have pulled the carb apart and cleaned everything in an ultrasoundwasher, it is even cleaner than before and blowed through with compressed air.

Here are the parts and sizing of the jets..

 

[NM850]

Your air jets are much too large. A rule of thumb is, main jet plus 50.
As a base line I would use 130 main jets and 175-180 air jets.
Idle jets at 45-50 should be good.
Venturi may be a little small for maximum power. But probably OK in a street car. In my 1000 I ran 28s.
All of it depends on how the engine is built, cam, compression etc but the above should be a good baseline.

 

[Jeff Stich]

28/36DCD jetting

I have ordered 45 idle jets, they ones I have may be too big... Here are the parts and sizing of the jets..

According to my 28/36DCD carb jetting notes for a Fiat 850/903/1000cc engine that I got long ago from John Rich, 50 idles should be about right, Mains should be in the 120-125 range, with corresponding Airs in the 175-180 range.

A good rule of thumb is to have the Main + Air equal to around 300, so 120 Main + 180 Air = 300 total, or 125 Main + 175 Air = 300, then you can fine-tune up or down a small increment on either to suit your (engine's) needs.

I agree with NM850's assessment of your Airs being a bit too large. On the setup you've shown, you might try a 45 idle in the Primary & put your 50 idle in the secondary, & adjust the Air correctors down to something in the 175-180 range. If that works a little better for you, you might then consider adjusting your venturi (choke) size(s) up a bit, perhaps going from the 24 up to a 26 on the Secondary side to see if there's a little more power to be gained.

Most important is to get the jetting settled first to where the car feels comfortably responsive enough to you, then you can try tweaking the choke size. And always remember: for best results, do one change at a time. :2c:

 

[Hermanzini]

Thank you very much for your input, guys! Much appreciated!
I have ordered some new jets and have my hands on some larger chokes, based on your tips.

I also noticed that I was missing the insulation plate between the manifold and the DCD, found this out when I heard the fuel boiling in the carb after a little trip and did a search on google....

I still have a lot to learn! :-D I am glad I found the 850 section here on Xweb, the best 850 forum I have found so far!

Thanks!