Quick question - where did you get this expansion tank? It's a nice size for turbo installs!

Also - I would recommend a water to air intercooler if you haven't already.

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Could you further explain how you would plan on adding additional oil squitors? That may be something I'm interested in.

Also, on a side note. What are your plans for head gasket?

Regarding the intercooler I promise to update soon. My wife and I are currently away celebrating our 1yr anniversary :)
You can buy the outlets and add them during the machining of the block. When you get to doing this as a full on build it would be an important step.
 
This was an great example I was trying to remember, but couldn't recall who it was. As Karl said he moved the "rod" portion of the dogbone down by off-setting it. That allowed it to clear under the fuel rail. That pic is a little deceiving due to the angle. Maybe Bjorn has a pic more from the side to show the profile?
This is the best pic I can get; the charge cooler is blocking me from having a full profile pic. The fuel rail is about 10mm above the tube.
IMG_20210831_185617.jpg
 
Could you further explain how you would plan on adding additional oil squitors? That may be something I'm interested in.

Also, on a side note. What are your plans for head gasket?

Regarding the intercooler I promise to update soon. My wife and I are currently away celebrating our 1yr anniversary :)
At the moment I don't plan to add any oil squirters. More on that later. But I understand it isn't too difficult to do so. There are some small "nozzles" used on other engines (e.g. Dodge Cummins diesels) that are very similar to the ones used on the later Fiat engines. They look like this (yellow tubes) - ignore the crowbar in the pic:

Cummins oil squirter - Copy.jpg


Basically they're a small pipe with a tiny nozzle on the tip. As you can see, a hole is bored through the upper bearing saddle in the block (red arrow on the left, above pic), facing the piston. Since the bearings are constantly being supplied with pressurized oil, the squirters will spray the oil directed toward the piston crown. The bearing shell itself also needs a corresponding hole drilled to allow the oil to pass. The location and angle of the hole through the saddle needs to be determined to aim the spray correctly (I'm not sure what the specs are for that). They have a step on the end and are a bit of a press fit, so the hole is straight but with a small recess:

103088577.jpg


The factory ones are plastic and probibly the best choice for a small engine. There are aftermarket ones made of aluminum but they also have a larger (custom) orifice to allow more oil to pass, which I think would be too much for our tiny oil system:
CDP_Bil_Squirters-750x750w.png

These squirters are readily available and not expensive. And the machine work to install them isn't difficult. As Karl said, it is something the machine shop can do when you are having other rebuild work done. You just need to determine the proper placement first (or maybe the machinist will know?).


However I'm not certain if these are needed or not. Having oil squirters is great for a turbo engine. Due to the added air and fuel, the combustion temps are higher and therefore things like piston crowns get hotter. And squirting oil on the back helps to cool them. But the X engine already has oil squirters, just a different type. The big ends of the rods each have a pair of tiny holes through the upper half. This is how they work:

Connecting+Rod+Construction+(Cont.).jpg


These act in the same way as the Dodge squirters, by allowing pressurized oil from the bearing to pass through and spray the piston. They may not provide as much spray as the Dodge squirters, so I don't know how they compare or if they are enough for a turbo X engine. But with a low boost application (e.g. less than 10psi) and a good tune on the ECU, there shouldn't be a need for excessive oil spray onto the crowns. Perhaps the stock holes in the rods could even be enlarged a tiny bit? But I agree, having proper squirters wouldn't hurt - for the most part. Keep in mind the more oil that is squirted out of the nozzles means less oil for the bearings and anything beyond them in the oiling circuit. So maybe it could hurt to have too much? Would you want to eliminate the stock ones if you installed additional (Dodge) ones?
 
Could you further explain how you would plan on adding additional oil squitors? That may be something I'm interested in.

Also, on a side note. What are your plans for head gasket?

Regarding the intercooler I promise to update soon. My wife and I are currently away celebrating our 1yr anniversary :)
Regarding the headgasket (HG). I'm sure I'll get some slack for saying this, but it seems to me the stock ones (including most of the aftermarket ones) have a MUCH higher failure rate than I'd consider normal. Just based on the number of HG failures that get reported on this forum, even after careful proper preparation, makes me think they must be a weak design.

Regardless if you agree or not about the standard gaskets, I think with a boosted application the HG becomes much more critical. So I'm of the opinion a multilayer steel (MLS) gasket should be used. That is the standard for boosted engines in general, so even with low boost levels it would be a good idea.

There are a couple of choices for a MLS HG. Cometic is a well known leading maker of MLS, and has been making one for the 14 bolt X engine for quite some time. For a few years they've been saying they are in the process of making one for the 10 bolt engine. I'm not sure what the current status is on that, I stopped asking after getting the same response of "should be next week" for two years. Another source is in Europe, but it is expensive and a little difficult to source. There is also a third choice from "Cleveland Gasket". I have no knowledge of them and not sure how they rate. They are also considerably more expensive than Cometic, but they currently offer both 10 and 14 bolt versions.

With a MLS HG you can choose the thickness when ordering it. So in the case of the US spec X, with very low compression, it might be good to go a little thinner than stock to increase the CR a bit. For reference the stock CR is around 8.2:1, and with a turbo you can go as high as 9:1 if everything is properly set up. 8.5:1 has been considered a good level for most boosted street applications where longevity and reliability are more important than all out power.
 
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On the subject of oil squirters. There are some considerations to look at.

As I mentioned the lubrication system as a whole needs to be capable of supplying the added oil demand without sacrificing oil supply to everything else. The volume (not pressure) of the oil pump needs to be sufficient. Unfortunately there aren't any high output volume options for SOHC oil pumps. Some oil squirters have a check valve built-in to prevent oil passing through them until it reaches a specified pressure. That helps to eliminate oil starvation at idle or low RPMs. And the size of the orifice needs to be calculated for the specific application. I'm not sure if the Cummins squirters do either of these effectively for the X engine. The issue of oil supply is why I ask if the stock squirter holes in the X's rods should be plugged when adding other squirters.

The design of the little holes on the stock rods may offer a benefit that the Cummins "add-on" won't. The big end of the rod (where the holes are) is at a fixed distance from the underside of the piston crown. So the spray from these holes will be pretty constant and always aimed toward them. Plus, as the rod big ends swing back and forth the spray will coat the entire underside of the piston. On the other hand the Cummins squirters are located on the block webs and therefore are not at a fixed length/location relative to the pistons. So the spray will hit the underside of the crowns sometimes but not always. And it may not offer as complete of coverage. It seems that will reduce their effectiveness in terms of piston cooling (the principle reason for them in our case).

As far as oil squirter designs go, there is yet another type usually referred to as "remote" ones. These are something designed along with the block because they feed directly from the oil galley running along the block, and their location is much more critical. Basically it consists of a arm that reaches out into the bore and aims the spray directly upward to the crown. The later Cummins used them instead of the tubes described earlier.
Engine-Misc.-Parts-Cummins-ISX-7065657.jpg

The OEMs seem to prefer this type, but they are specifically designed as part of the oiling system inherent in the engine. I don't think it would be practical (or wise) to try and mimic this on the SOHC. There is too much room for screwing up the lubrication system.

Other concerns may be things like windage issues. Spraying oil into the crankcase is basically working opposite to all of the efforts engine builders do to reduce excess oil from floating around in there. I read tests where they actually reduced power. Although in the case of a boosted engine oil squirters are more about reliability than ultimate power. Some also question how much boring holes into the block's journal/web weakens it, or can lead to cracks.

All of these considerations are why I decided not to add any squirters to my build. At least not unless I can find more information regarding the amount of oil any of them pass, how much spray is actually needed, how effective they are at prolonging the life of the pistons in these specific engines, and to what degree the existing ones will suffice. If anything I might consider the possibility of slightly opening up the existing holes in the X's rods (but again, more knowledge is needed first).


EDIT: I intended to add this pic of the factory oil squirters that Fiat uses on some of the newer (relative to the X) engines:
Fiat oil injectors.jpg

They are installed very similar to the description given for using the Cummins (plastic) ones. It would be helpful if the specs for both (Fiat and Cummins) could be found and compared.
 
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I saw a good pic of a X1/9 connecting rod that helps illustrate the stock oil squirters. So I'll borrow the pic and highlight them.

Each rod has two oil squirters, one on either side of the rod. This pic is only one side. The red arrows show the inlet and outlet of the hole for one squirter. The green line is to show how the hole is angled to aim the spray toward the piston. The blue arrow is the inlet hole for the squirter on the other side of the rod. They are oriented in opposite directions to offer more coverage of the piston.

s-l1600 (3).jpg


The oil is pressurized to the rod bearing. These holes route some of that pressurized oil away from the bearing and spray it at the piston. I'm not sure if there has been any good analysis of how this approach compares to the remote squirters shown in a previous post. However regardless of the type or location of the squirters, all of them will take some oil away from the rest of the lubrication system. So you don't want to over do it.
 
I saw a good pic of a X1/9 connecting rod that helps illustrate the stock oil squirters.
I didn't know that also the X1/9 engine has oil squirters. If this is true it should be ok to lower compression and put boost on it. -A lot of boost, as this engine is probably not weaker than the UT engine.
This is the UT engine. I haven't seen an equivalent picture for the X 1.5l so if someone has it please post it.
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The green line is to show how the hole is angled to aim the spray toward the piston. The blue arrow is the inlet hole for the squirter on the other side of the rod. They are oriented in opposite directions to offer more coverage of the piston.

View attachment 52180

Actually the oil holes in the conrod big end don't aim to the piston underside, they spray at the cylinder wall. (and all sohc and dohc engines have them in some manner like this) SCAT aftermarket rods do not have the cylinder wall spray holes drilled.

Whereas the supplementary oilers off the main bearing journals as used by the Uno turbo engine definitely spray right up at the piston crown underside.

SteveC
 
I didn't know that also the X1/9 engine has oil squirters. If this is true it should be ok to lower compression and put boost on it. -A lot of boost, as this engine is probably not weaker than the UT engine.
This is the UT engine. I haven't seen an equivalent picture for the X 1.5l so if someone has it please post it.
Piston underside squirters are only part of the story of the cooling differences between an X19 1500 and an Uno Turbo engine.

One is 80.5mm bore size and one is 86.4mm bore size, so the difference in material between the cylinders at the head gasket deck is obvious, the bore centrelines / spacing are the same, so the larger bore of the 86.4 bore bock means roughly 6mm more material between the cylinders, that's easy to see....

What is not so obvious is the material you cant see, the material that isn't there in the Uno T block. The 86.4 block has cylinders siamesed, i.e they are co-joined along the adjoining wall, no water passes thru the block along the area between these cylinders. The Uno Turbo block is different in that the cylinders are NOT siamesed and water can flow between all the cylinders and completely around the circumference of the bore


This is the single biggest difference in the cooling ability of the two engine types.

Where the head gasket tends to fail most often is between cylinders 2 and 3, as it's only this point where the exhaust valves for two cylinders are adjoining and (likely) to be the point of most thermal potential especially when coupled with siamesed cylinders. The SOHC's original design of 1116cc (80 x 55.5) has NON siamesed cylinders, siamesing the cylinders began in the SOHC's second iteration as a 1290cc engine when the bore was enlarged to 86mm.

SteveC
 
I have a question on bearings (main and connecting rod) for the Mk1 UT engine - the 1.3L Mk1 UT bearings are not the same part number as the 1500cc engine, but they do fit - I'm going to need a set real soon for my Mk1 - is there a good source for the proper bearings? I haven't found any reliable source to buy them (prefer not to buy from Ebay, and I certainly want high quality bearings in standard size).

Thanks! (slightly off topic, but I see lots of convo around connecting rods so I thought I'd chime in!) :)
 
I have a question on bearings (main and connecting rod) for the Mk1 UT engine - the 1.3L Mk1 UT bearings are not the same part number as the 1500cc engine, but they do fit - I'm going to need a set real soon for my Mk1 - is there a good source for the proper bearings? I haven't found any reliable source to buy them (prefer not to buy from Ebay, and I certainly want high quality bearings in standard size).

Thanks! (slightly off topic, but I see lots of convo around connecting rods so I thought I'd chime in!) :)
It's a tiny fractional difference in size that is the difference.... so you may find that regular 1500 bearings will give the oil clearance you require, just depends how worn your standard crank is.

SteveC
 
It's a tiny fractional difference in size that is the difference.
Thank you - interestingly though, they have a different amount of holes on either the crank or connecting rods - I just can't recall which one is which.
Eventually the engine will go off to the rebuilder - they can measure the crank, issue is that the UnoT was never sold here and finding bearings always means ordering them from overseas. So I figured I'd have a set of fresh standard ones on hand :)
 
Thank you - interestingly though, they have a different amount of holes on either the crank or connecting rods - I just can't recall which one is which.
Eventually the engine will go off to the rebuilder - they can measure the crank, issue is that the UnoT was never sold here and finding bearings always means ordering them from overseas. So I figured I'd have a set of fresh standard ones on hand :)
no the uno T mk 1 conrod and the X19 1500 conrod are the same thing, it's the same rod.. no difference in oil spayer holes... it's the journal size of the crank that is fractions of a thou difference in size.

what's probably confusing you is the modern batch of bearings for 1500 X19 also double use as big end bearings for 1100/300 conrods as well... the difference in 1300 and 1500 is the position of the bore wall sprayer holes, so you will find some bearings will do both styles and have three oil holes in the upper shell, of which for either application only two get used.

Main bearings look identical for 1100/1300/1500 and unoT but again it's tiny fractional differences in the actual crank journal size.

SteveC
 
Whereas the supplementary oilers off the main bearing journals as used by the Uno turbo engine definitely spray right up at the piston crown underside.
With the UT oil squirters mounted in the block, they have a fixed position with a fixed oil spray. Therefore the piston will be at different positions relative to the actual spray of oil as the piston continually moves up and down through the stroke. So the spray will hit the piston for a portion of its travel as the crank rotates, but not during the rest of the crank rotation when the piston is in a different location in the cylinder. The spray hits the cylinders when the piston is not in direct alignment with the spray.

When turbo engine builders are converting a non-turbo engine for use with boost they often redirect the angle of the oil squirter to aim it at the piston crown. If desired this could be done on the X by angling the little holes in the rods slightly differently. Between doing that and adding additional oil squirters to the block (ala UT style), it might be a question of what is easier to do, which has a greater effect on the piston's life, and how much is actually needed for a specific spec of build. I imagine for the X engine with a low boost turbo there really isn't any need to add more squirters or modify the existing ones. :)
 
Interesting thread, drifting as usual 😀.
I didn't think about the non siamesed cylinders on the UT which makes room for more water cooling and there is probably other differences as well.
My absolute favorite driver/car/build is Johannes Graversen from Denmark. I wonder what kind of block he used on his 370hp/340Nm@1.5 bar build:
-1425 cc
-Bore 86.4 mm
-Stroke 61 mm
-CR 6.5:1
As Steve S says, the cylinder walls would be very thin if reboring an UT to 86.4 mm so how did he manage?
The stroke is rather short. -A way to lower compression and making it rev to10k rpm?
It seems like Graversen used a 1500 block of some sort with shorter con rods.
 
Interesting thread, drifting as usual 😀.
I didn't think about the non siamesed cylinders on the UT which makes room for more water cooling and there is probably other differences as well.
My absolute favorite driver/car/build is Johannes Graversen from Denmark. I wonder what kind of block he used on his 370hp/340Nm@1.5 bar build:
-1425 cc
-Bore 86.4 mm
-Stroke 61 mm
-CR 6.5:1
As Steve S says, the cylinder walls would be very thin if reboring an UT to 86.4 mm so how did he manage?
The stroke is rather short. -A way to lower compression and making it rev to10k rpm?
It seems like Graversen used a 1500 block of some sort with shorter con rods.
We talked about all this before in another thread, and I mentioned the multiplication factor and use of the standard production block being reasons the engine is configured like this...

anyway not long after that thread in Jan 2021 I sold some parts thru my ebay store to Graversen's in Denmark, so I asked the fellow who ordered the parts about the race X19.

Steen Graverson (was either the nephew or grandson of Johannes I can't recall) said the car was built back in the mid 1980's and yes that was the class structure back then, requiring the use of the original engine block and transmission casing, but pretty much all internals were free, and a 1.4 multiplication factor applied. In later years the class was altered, but Johannes never felt the need to change a reliable combination.

Johannes retired from racing in 2018 at the age of 74, and they still have the car.

SteveC
 
With the UT oil squirters mounted in the block, they have a fixed position with a fixed oil spray. Therefore the piston will be at different positions relative to the actual spray of oil as the piston continually moves up and down through the stroke. So the spray will hit the piston for a portion of its travel as the crank rotates, but not during the rest of the crank rotation when the piston is in a different location in the cylinder. The spray hits the cylinders when the piston is not in direct alignment with the spray.

When turbo engine builders are converting a non-turbo engine for use with boost they often redirect the angle of the oil squirter to aim it at the piston crown. If desired this could be done on the X by angling the little holes in the rods slightly differently. Between doing that and adding additional oil squirters to the block (ala UT style), it might be a question of what is easier to do, which has a greater effect on the piston's life, and how much is actually needed for a specific spec of build. I imagine for the X engine with a low boost turbo there really isn't any need to add more squirters or modify the existing ones. :)
Actually the crank web mounted sprayers are aimed roughly at the centre of the bore, they don't have the conrod in the way, so the relative position of the piston up or down the bore wont make an appreciable difference over the engines 63.9mm stroke to where the spray will point, it will still be roughly the middle of the piston, certainly on the piston crown underside where it's going to have the most benefit.

Fiat crankcase web mounted sprayers are nothing like the cummins items pictured either. The Fiat parts have a ball check valve inside, which only unseats once engine oil pressure exceeds about 1.5 bar from memory, so idling oil pressure isn't affected by the additional oil bleeding off. There is also no need for additional holes drilled in the main bearings as the sprayer takes oil from the circumferential groove in the main saddle.

You're also not going to get an appreciable effect by altering the rod sprayer angle... think about it... the oil spray is timed - it's not (semi) continuous like the UnoT piston underside cooling spray.

There is a cross drilling in the crank that puts the supply hole in the crank journal at right angles to the piston/rod when at TDC, so this cross drilling only aligns with the rod sprayer hole when the piston is roughly half way down the bore and the con-rod is at a considerable angle and the spray holes are pointing towards the bore walls and gudgeon pin bore in the piston.

SteveC
 
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