Dr.Jeff
True Classic
Grease is how the man got fat. So it is all the same meaning.
1964 fiat 600 (perhaps) cassetta Abarth
- Thread starter Oriebi
- Start date
Dr.Jeff
True Classic
Sometimes the way it was done originally isn't necessarily the best design. So making improvements to suit your needs is not only o.k., but mandatory in my opinion.
Another great job.
Oriebi
Daily Driver
Thank you!
As i said yesterday, the other job to do was to check the engine. For some time we had noticed a slight consumption of water, so about three weeks ago we disassembled everything.
As expected, there was a noticeable sign of corrosion on the edge of the fourth cylinder, which caused the bench (engine block) to be flattened by about 1/10 mm. Considering that the head had already been leveled several times, we had to be careful of what type of gasket to mount; so we aimed for a reinforced one with a thickness of 1.80 mm.
But as they say in Italy, we go there to look for evil like doctors.
We did not understand the origin of that strange vibration: we discovered it when inspecting the block we saw a crack that passed transversely the block under the engine support on the distribution side. The first photos you see are during the repair phase in a specialized mechanical workshop.
Excellent work of this workshop, welding and boring of the crankshaft and camshaft seats performed in a workmanlike manner. However, it is necessary to know how much the theoretical compression of the engine has come, at least to have an idea on how to deal with any problems.
As i said yesterday, the other job to do was to check the engine. For some time we had noticed a slight consumption of water, so about three weeks ago we disassembled everything.
As expected, there was a noticeable sign of corrosion on the edge of the fourth cylinder, which caused the bench (engine block) to be flattened by about 1/10 mm. Considering that the head had already been leveled several times, we had to be careful of what type of gasket to mount; so we aimed for a reinforced one with a thickness of 1.80 mm.
But as they say in Italy, we go there to look for evil like doctors.
We did not understand the origin of that strange vibration: we discovered it when inspecting the block we saw a crack that passed transversely the block under the engine support on the distribution side. The first photos you see are during the repair phase in a specialized mechanical workshop.
Excellent work of this workshop, welding and boring of the crankshaft and camshaft seats performed in a workmanlike manner. However, it is necessary to know how much the theoretical compression of the engine has come, at least to have an idea on how to deal with any problems.
Oriebi
Daily Driver
So, we know that the compression ratio is calculated with the formula (v1 + v2) / v1
v1 = head chamber volume
v2 = volume of air sucked into the cylinder, practically the volume between lower and upper dead center.
Do not forget the volume in charge of the head gasket, which we decided to consider of 1.50 height from the tablet.
my wife is always very precise with the calculations. In the end the result is 12.66: 1. Not bad, a little high, but not excessive.
These days other works and spare parts coming soon ...
v1 = head chamber volume
v2 = volume of air sucked into the cylinder, practically the volume between lower and upper dead center.
Do not forget the volume in charge of the head gasket, which we decided to consider of 1.50 height from the tablet.
my wife is always very precise with the calculations. In the end the result is 12.66: 1. Not bad, a little high, but not excessive.
These days other works and spare parts coming soon ...
Dr.Jeff
True Classic
To me that is a little high for a street driven car, but I understand it wasn't avoidable. Hopefully you have high octane fuel available.
The crack repair looks good, that is difficult to do right.
myredracer
True Classic
I have a thicker head gasket in my 1050 cc engine (built on a 903 cc block) which is 1.6 mm I believe. I would have to go look for my engine build specs, but I think the CR is around 10.5 to 1 compared to stock 9.8 to 1. My A112 head is brand new which will lower the CR compared to yours. You could always increase the volume in the combustion chambers but that is a lot of work.
Here is a link to the Guy Croft forum where someone posted info. on porting & modifying an A112 head that you might find of interest Iif you haven't seen it). http://www.guy-croft.com/viewtopic.php?t=2788
You might also find some good info. in Paul vander Heyden's article on building a high performance 850/A112 engine (from about 10 years ago). https://myfiat600d.wordpress.com/2018/07/06/scuderia-topolino/
Just a thought - you could try posting on the Facebook Fiat 850 forum about an A112 engine. Paul vander Heyden posts info. on engines there and he has a lot of tech. knowledge on 850 & A112 engines.
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Oriebi
Daily Driver
exactly! that's the problem. the head has been too flattened previously, we have calculated the cr with excess approximation, given that the gasket is 1.80 high, but I am convinced that even by making the calculations it will not go down much. The ideal would be a new head however not flattened like that.
thanks for the links, I will spend an evening of study and study!
thanks for the links, I will spend an evening of study and study!
Oriebi
Daily Driver
here I am again. today we did some less demanding jobs.
The new intake valves have arrived (the old ones had too much play and in the fourth the chrome plating had worn out) and after finishing them, they are ready. In the photos you will see the raw valve on the left and connected and finished on the right.
the intake manifold is of an 850, it has been cleaned and well connected with the head and with the homemade spacer with bakelite. The spacer became necessary because the engine of the 850 is slightly inclined; in doing so I finally have the carburettor and the air filter no longer tilted to the left.
The new intake valves have arrived (the old ones had too much play and in the fourth the chrome plating had worn out) and after finishing them, they are ready. In the photos you will see the raw valve on the left and connected and finished on the right.
the intake manifold is of an 850, it has been cleaned and well connected with the head and with the homemade spacer with bakelite. The spacer became necessary because the engine of the 850 is slightly inclined; in doing so I finally have the carburettor and the air filter no longer tilted to the left.
Dr.Jeff
True Classic
Nice job of cleaning up the new valves.
Forgive me for asking, but I am not very familiar with 850/A112 engine applications. If you have a A112 block and head (I think that's what I understood?), then why use the 850 intake manifold? To keep it looking "original"? I assume the 850 manifold required some work to connect with the A112 head, and the A112 manifold would offer much more performance. So it seems using the A112 manifold would be good? However I also understand if it is for cosmetic reasons (i.e. to look like a 850 engine).
Or am I completely wrong and you have a A12 block and 850 head? In which case the same question about using the A112 head instead of the 850 head?
Again, I am just curious because I have never been involved with 600, 850, or A112 engines.
Forgive me for asking, but I am not very familiar with 850/A112 engine applications. If you have a A112 block and head (I think that's what I understood?), then why use the 850 intake manifold? To keep it looking "original"? I assume the 850 manifold required some work to connect with the A112 head, and the A112 manifold would offer much more performance. So it seems using the A112 manifold would be good? However I also understand if it is for cosmetic reasons (i.e. to look like a 850 engine).
Or am I completely wrong and you have a A12 block and 850 head? In which case the same question about using the A112 head instead of the 850 head?
Again, I am just curious because I have never been involved with 600, 850, or A112 engines.
myredracer
True Classic
Same question, curious why an 850 manifold? With 1050 cc, I would use a DCD carb and DCD manifold (for a 600). DCD carbs are a lot more tune-able than an 850 stock carb. Also, a DCD intake manifold can be "opened up" more.
Oriebi
Daily Driver
you are right, but it was done for two reasons.
The first is that for some obscure reason, the Abarth A112 tappet cover had touched the bulkhead of the engine compartment, so it was replaced by the old owner with the aluminum one of the 850, consequently, the carburettor base of the tappet cover was missing, they mounted that 850 by adding two prisoners. As a carburettor I have a Holley (weber) 30dic.
The second reason is that we only started the engine during this period, since it has never given any problems up to now. Rather! It was going too fast.
The parts were probably previously mounted on one of the engines that we had as spare parts when we purchased the car.
The first is that for some obscure reason, the Abarth A112 tappet cover had touched the bulkhead of the engine compartment, so it was replaced by the old owner with the aluminum one of the 850, consequently, the carburettor base of the tappet cover was missing, they mounted that 850 by adding two prisoners. As a carburettor I have a Holley (weber) 30dic.
The second reason is that we only started the engine during this period, since it has never given any problems up to now. Rather! It was going too fast.
The parts were probably previously mounted on one of the engines that we had as spare parts when we purchased the car.
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Oriebi
Daily Driver
I can't get those beautiful changes out of my head. They would be very feasible, but I have to admit that the car is already going strong enough to make me give up.
While I am writing I place the diagram of the camshaft that I have mounted. We imagined that it had been replaced, but that was a nice surprise too.
I hope you read it well.
While I am writing I place the diagram of the camshaft that I have mounted. We imagined that it had been replaced, but that was a nice surprise too.
I hope you read it well.
ghostdancing
True Classic
orebi what ignition setup you have on the 600?
Oriebi
Daily Driver
Sorry if I answer only now! Regarding the setup, we still have to do it.
To help us better adjust the advance we have graduated the crankshaft pulley up to 4 ° applying the formula of conversion from degrees to millimeters.
Some spare parts are still missing so in a few days we will be able to start again with the engine assembly.
To help us better adjust the advance we have graduated the crankshaft pulley up to 4 ° applying the formula of conversion from degrees to millimeters.
Some spare parts are still missing so in a few days we will be able to start again with the engine assembly.
kmead
Old enough to know better
In a 600 or an 850 you can’t use the A112 valve cover (which also includes the intake manifold as part of the casting) as it would cant the carburetor at the wrong angle and the wrong orientation of the carb. The opening into the head is effectively the same for both the A112 and the 850 head. So one uses the early 850 or an Abarth or similar intake manifold along with a 850 valve cover.
myredracer
True Classic
Also, using an A112 valve cover means the filler cap will be at the opposite end. Have seen many photos of folks who have done it but would be a bit of a nuisance for adding oil plus it just doesn't look right.
Another thing is that a 600 valve cover will be needed because the throttle cable angle is different where it comes from the firewall to the valve cover. The various 600 & 850 rocker covers have a few different sizes and angles of the oil vapor vent pipe exiting the side of the filler tube/cap.
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Dr.Jeff
True Classic
Just for interest sake, talking about induction set ups....
In another thread someone posted a link to a seller on eBay that has a lot of carbs and manifolds. That seller is a member here and has posted about his performance 128 before (haven't heard from him in a while). I noticed in his eBay listings he has a couple of performance induction systems for the A112, 850, 600, etc, including a neat Abarth one. You'll have to scroll through his items for sale to find it:
https://www.ebay.com/sch/jimgkiouli...e=STRK:MEBIDX:IT&rt=nc&_trksid=p2047675.l2562
That is from the USA eBay, however the seller is in Greece so you might find his stuff on other country eBays (possibly even Italy).
In another thread someone posted a link to a seller on eBay that has a lot of carbs and manifolds. That seller is a member here and has posted about his performance 128 before (haven't heard from him in a while). I noticed in his eBay listings he has a couple of performance induction systems for the A112, 850, 600, etc, including a neat Abarth one. You'll have to scroll through his items for sale to find it:
https://www.ebay.com/sch/jimgkiouli...e=STRK:MEBIDX:IT&rt=nc&_trksid=p2047675.l2562
That is from the USA eBay, however the seller is in Greece so you might find his stuff on other country eBays (possibly even Italy).