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So, this is how it goes. First time Alfa owner. Here I will ask some questions about my engine build-thanks for all answers. So, some history... The car is 1974 US spider with SPICA engine. I never drove the car, so I dont know anything much about the engine. I guess last time it drowe was about 10 years ago. When I got the car I needed about two days to start the engine. I could only run it for a minute or two, since there was no cooling etc. Engine was all greasy and I saw the oil in cooling water so I decided for a rebuild. Before I pulled it out of the car I measured compression -cold. The numbers was about 170 PSI on all four cyl. After that I put som oil in the cylinders and measured about 180-185 on all four cylinders. Numbers do not seem bad. Today, I took the head off. I think cylinders does not look bad, crosshattch can be seen on the walls. So, question is, should i replace the liners and pistons with new, lets say with motronic ones, or these should be OK.? I want a good engine with no problems, but still, I dont want to throw money through the window if it is not neccessary... what do you think?

Oh, maybe important info, I would like to tune the engine a bit, nothing radical, lets say euro cams, some head work, better exhaust...

Thanks!
 

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busstjan said:
should i replace the liners and pistons with new, lets say with motronic ones, or these should be OK.? I want a good engine with no problems, but still, I dont want to throw money through the window if it is not neccessary...
You're right, your compression numbers don't sound bad. An engine with even, 170 psi compression readings will run well. Just checking the head for straightness and replacing the head gasket will probably solve the oil-in-coolant problem and give you an engine that should last for another xxx miles.

Sure, fresh rings and domed pistons will increase the compression numbers. And replacing the water pump, oil pump, chains, valves, bearings, ..... while you're at it will result in an engine that will last longer than xxx miles. So would doing all that be "throwing money through the window"? I dunno - depends on how deep your pockets are, how long you plan on keeping this car, what kind of shape the body is in, etc. etc.

I would like to tune the engine a bit, nothing radical, lets say euro cams, some head work, better exhaust...
That's a whole different question, as well as a whole different level of spending.
 

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I just built a Motronic-piston 2000 for a 74 GTV. Not many true Motronic pistons sets left, from what I hear. Some sold as "Motronic" are in fact 10.4 round-top ones, not the same thing. There is a rant on the BB elsewhere about Vick's on this point.

My experience is the appearance of cross-hatchingi doesn't tell you much. And you can have great compression rings with useless oil rings. The 2000 I built had 180 lbs compression but burned a quart every 200 miles. The rings can wear out differently.

Andrew
 

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You're right, your compression numbers don't sound bad. An engine with even, 170 psi compression readings will run well. Just checking the head for straightness and replacing the head gasket will probably solve the oil-in-coolant problem and give you an engine that should last for another xxx miles.

Sure, fresh rings and domed pistons will increase the compression numbers. And replacing the water pump, oil pump, chains, valves, bearings, ..... while you're at it will result in an engine that will last longer than xxx miles. So would doing all that be "throwing money through the window"? I dunno - depends on how deep your pockets are, how long you plan on keeping this car, what kind of shape the body is in, etc. etc.



That's a whole different question, as well as a whole different level of spending.
Yes, the car is actually in good shape and I want to restore it properly. It is a SoCal car, so almost no rust with no accidents. I want to keep the car and drive it in Summers, lets say abour avg 2000mls /year max. But it will be driven quick on steep Alpine roads, so the engine will be under high load a lot. So, it has to be good for at least next 30 000 mls.

I do not want to experiment with parts deep in the engine so probably I will just replace everything what I suspect it will fail. . I asked for opinion since I have no experience with these engines...
The car has 59000mls on the odometer and I assume they are real. Is it necessary to replace also chains, oil pump, valves at this mileage? what is the praxis? Waterpump I already have new...




I just built a Motronic-piston 2000 for a 74 GTV. Not many true Motronic pistons sets left, from what I hear. Some sold as "Motronic" are in fact 10.4 round-top ones, not the same thing. There is a rant on the BB elsewhere about Vick's on this point.

My experience is the appearance of cross-hatchingi doesn't tell you much. And you can have great compression rings with useless oil rings. The 2000 I built had 180 lbs compression but burned a quart every 200 miles. The rings can wear out differently.

Andrew
Yes, the thing you wrote, with good compression and burning oil I am scared off.

Now, which pistons should I buy that will suit my engine, lets say from classicalfa?

https://classicalfa.com/105-spider-parts/engine-block/


They also say they have motronic pistons...? Are they good?

https://classicalfa.com/en005-1-2000-spider-1988-93-piston-liner-set/


Thanks
 

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Reuse the pistons & liners

Hi Busstjan

170 PSI is a very good number. To the other posters, what do you regard as a good number? 200 PSI? More?

Anyway reliability comes from the bottom end, power comes from the head.

Flip the motor over, pull the crank, remove the plugs, have it hot tanked. Knock out the connecting rods / pistons clean & measure them, if they are in spec (and I suspect they are) reinstall them with new Hastings brand rings. Get new rod and main bearings, get a gasket set with a german made head gasket. Blow out the oil passages in the block.

Disassemble the head, replace the valve springs, replace the other parts as needed. I always replace the exhaust valves.

Disassemble the oil pump, measure & clean it, and check the operation of the pressure relief valve.

Don't be replacing old OEM parts without a good reason.The new parts are rarely as good as the old OEM ones. The old parts have also been heat cycled and have now "settled" into their final shape.

Hope this helped
 

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To what others have said I'd add that if the SPICA is in good shape to start out with and you learn how to set it up properly (lots of threads regarding how to do that) then you will have a good running motor. A 10548 euro cam is not a bad improvement on the intake side (leave the cam on the exhaust side). Leave the stock exhaust - they are excellent as is. Do not replace the SPICA airbox with aftermarket filters. Replace the ignition with either a Pertronix electronic module or replace the whole dizzy with a programmable 123 unit.

BTW, the '74 version of the SPICA pump was the highest performing pump - it was downhill from there...
 

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What is the praxis?
Beats the heck out of me. Did I use the term "praxis"? Can't find it in my post.

Is it necessary to replace also chains, oil pump, valves at this mileage?
Probably not the chains and oil pump. Your head machinist will decide if the valves can be re-used; a lot depends on whether an overly lean mixture has burned them. As Milanoguy wrote, often exhaust valves need replacing.

At a minimum the oil pump should be disassembled, inspected and cleaned. As Milanoguy wrote, make sure the pressure relief valve bore has no burrs and that the valve doesn't bind.
 

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Discussion Starter #8
Hi Busstjan

170 PSI is a very good number. To the other posters, what do you regard as a good number? 200 PSI? More?

Anyway reliability comes from the bottom end, power comes from the head.

Flip the motor over, pull the crank, remove the plugs, have it hot tanked. Knock out the connecting rods / pistons clean & measure them, if they are in spec (and I suspect they are) reinstall them with new Hastings brand rings. Get new rod and main bearings, get a gasket set with a german made head gasket. Blow out the oil passages in the block.

Disassemble the head, replace the valve springs, replace the other parts as needed. I always replace the exhaust valves.

Disassemble the oil pump, measure & clean it, and check the operation of the pressure relief valve.

Don't be replacing old OEM parts without a good reason.The new parts are rarely as good as the old OEM ones. The old parts have also been heat cycled and have now "settled" into their final shape.

Hope this helped
Hi, yes I understand, I was more in BMW classic waters till I got this alfa and I know that many times, new parts, (original BMW!) are worse and lasts 10 times shorter than 30 or 40 year old BMW part. Probably it is the same with Alfa...

If I go in this direction- to use existing pistons and liners, probably I have to fresh hone the liners then?
I don`t know If I will get Hastings rings here ( I live in Europe), but I will try to find these ore some other quality ones. The rest I will do as you say, springs, valves etc. I will buy new.

Which company made original pistons+rings, Borgo, Nural?-maybe I can get good rings from them...

To what others have said I'd add that if the SPICA is in good shape to start out with and you learn how to set it up properly (lots of threads regarding how to do that) then you will have a good running motor. A 10548 euro cam is not a bad improvement on the intake side (leave the cam on the exhaust side). Leave the stock exhaust - they are excellent as is. Do not replace the SPICA airbox with aftermarket filters. Replace the ignition with either a Pertronix electronic module or replace the whole dizzy with a programmable 123 unit.

BTW, the '74 version of the SPICA pump was the highest performing pump - it was downhill from there...
Yes, I like Spica very much-it is interesting to me how it works, also because car will stay original and here in Slovenia (neighbours of Italy) are almost no Spica cars. I know quite a lot about Spica, reading all these threads and book from Wes Ingram etc., so I hope that I will be able to adjust it when I come to there. Airbox will stay-it looks good design and sucks cold air-I really dont know why people put these small funny filters on throttle bodies...

I think that in the beginning I will use stock cams, and then upgrade...
I will use electronic ignition, thanks...


Beats the heck out of me. Did I use the term "praxis"? Can't find it in my post.




Probably not the chains and oil pump. Your head machinist will decide if the valves can be re-used; a lot depends on whether an overly lean mixture has burned them. As Milanoguy wrote, often exhaust valves need replacing.

At a minimum the oil pump should be disassembled, inspected and cleaned. As Milanoguy wrote, make sure the pressure relief valve bore has no burrs and that the valve doesn't bind.
Praxis-Sorry, maybe I used wrong term translating from my language in English...:wink2:
 

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Discussion Starter #9
Does maybe anyone have experience from europe webshops like Classicalfa or Alfaholics, do they have quality engine parts? Like chains, valves, valve guides, piston rings, bearings etc. Some parts are so cheap that I am a bit sceptical...
 

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I have not bought anything from Classic Alfa I was not happy with. So yes, all good. I don't imagine that many companies are making Nord engine parts any longer? I hear anecdotally that OKP in Germany is responsible for most of the productions and others jump onboard. Just what I hear, I don't know for sure. But they seem to be the big gorilla of Alfa parts in Europe.

Andrew
 

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I think I wrote it somewhere here before but again.
There is a difference between the Motronic for Spider and for Alfetta. Look at the picture.
Spider Motronic pistons are not 10:1 whereas Alfetta piston are.

left Motronic piston compl. with rings and rod 622 Gramm,ORGINAL MOTRONIC KOLBEN for ALFETTA !
right Spider Serie 4 piston compl. with rings and rod 628 Gramm ,nowadays very often sold as Motronic Kolben



I just did a rebuild on my engine with the Alfetta pistons, you can buy them here:

https://www.myalfagroup.com/de/ersatzteile/spider-105-115/motor/motorblock/kolben-buchsen/kolben-laufbuchse-2000-motronic.html

Salutations from the Baltic Sea

Bernhard
 

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Discussion Starter #13
I think I wrote it somewhere here before but again.
There is a difference between the Motronic for Spider and for Alfetta. Look at the picture.
Spider Motronic pistons are not 10:1 whereas Alfetta piston are.

left Motronic piston compl. with rings and rod 622 Gramm,ORGINAL MOTRONIC KOLBEN for ALFETTA !
right Spider Serie 4 piston compl. with rings and rod 628 Gramm ,nowadays very often sold as Motronic Kolben



I just did a rebuild on my engine with the Alfetta pistons, you can buy them here:

https://www.myalfagroup.com/de/ersatzteile/spider-105-115/motor/motorblock/kolben-buchsen/kolben-laufbuchse-2000-motronic.html

Salutations from the Baltic Sea

Bernhard

Interesting, thanks. Is there a big difference in power when you compare it with stock pistons? Is there any problem with knocking because of higher compression?
 

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Hello,

just to be complete

left Standard Piston Typ 2000 with rings and rods 604 Gramm
right:Orginal Mahle piston, forged piston,complete 518 Gramm

A standard piston will give you 9:1, the Mahle 10,4:1, the Alfetta 10:1 and the Series 4 9,5:1 ( might be a little higher, but never 10:1 )

Of cause there is an increase in power, but this will not be with pistons alone, there is some more to do: cams, ignition, valves, cam timing and the Spica pump etc....

Higher compression can cause pinging. With the use of better fuel and or different ignition timing this should be no problem.

Salutations from the Baltic Sea

Bernhard
 

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Interesting, thanks. Is there a big difference in power when you compare it with stock pistons? Is there any problem with knocking because of higher compression?
Not sure what octane gas you have available where you are, but I'd be really careful with increasing the compression. You'd probably have the best results with a mildly ported head and cams from RJ (alfar7). Alfaparticle has done some great work on a Nord engine running on US pump gas. https://www.alfabb.com/bb/forums/spider-105-115-series-1966-1994/676728-79-spider-dyno-sequel.html

Any SPICA build is going to be limited in power by the SPICA unit. When I built my engine, I had Wes build a SPICA unit to work with the cams and head I used.

I haven't bought any engine parts from Alfaholics, but their prices are rather high. It appears most of their engine parts are available elsewhere except for their long-strike crank.
 

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Hi there, have you torn this engine down to bits already? If your bottom end is still all together I would just leave it. Your symptom of oil in water can be solved with a head gasket change. Compression of 170 and even I think is really good, especially with no huge increase with oil. How was oil pressure when you had it running briefly? Since the engine is out of the car already I would change the front and rear crank seals. Since the engine is out and the car sat for a long time I would also recommend putting some time into your spica fuel injection pump, read roadtrips bench check guide, suck some oil out of the logic section and make sure there is no fuel mixed with it. Make a dummy TA and set your nineteen thou, confirm your bell crank stops, etc while the engine is out too. Unless you have a burning desire to rebuild the engine because you just really want too, my view is the time, energy, money are better spent elsewhere. Like lightweight flywheel, change the synchros, rebuild front and rear suspension, new tires, 123 distributor, rebuilt spica pump if you have fuel in the oil.

There is a chance that with 170 cold on a not freshly rebuilt engine that you already have some kind of high compression piston installed or shaved head or something.

Cheers,
 

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Crank

I haven't bought any engine parts from Alfaholics, but their prices are rather high. It appears most of their engine parts are available elsewhere except for their long-strike crank.
And those are available from Jon Norman. Alfa Parts in Bezerkley, Ca.
 

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Not sure what octane gas you have available where you are, but I'd be really careful with increasing the compression. You'd probably have the best results with a mildly ported head and cams from RJ (alfar7). Alfaparticle has done some great work on a Nord engine running on US pump gas. https://www.alfabb.com/bb/forums/spider-105-115-series-1966-1994/676728-79-spider-dyno-sequel.html

Gas here is pretty high quality, 95, 98 or 100 octane gas. In reality octane numbers are probably a bit lower, but still, it is good, so I think there shouldnt be a problem with that.

Any SPICA build is going to be limited in power by the SPICA unit. When I built my engine, I had Wes build a SPICA unit to work with the cams and head I used.

I haven't bought any engine parts from Alfaholics, but their prices are rather high. It appears most of their engine parts are available elsewhere except for their long-strike crank.
Gas here is pretty high quality, 95, 98 or 100 octane gas. In reality octane numbers are probably a bit lower, but still, it is good, so I think there shouldnt be a problem with that.
For now, I have two spica 1974 Pumps, one came with the car, the other one I bought in italy and has very low miles on It, it looks almost like new. First, I want to run the engine and then, if I will have to, send it to Wes to build it to my setup.


Hi there, have you torn this engine down to bits already? If your bottom end is still all together I would just leave it. Your symptom of oil in water can be solved with a head gasket change. Compression of 170 and even I think is really good, especially with no huge increase with oil. How was oil pressure when you had it running briefly? Since the engine is out of the car already I would change the front and rear crank seals. Since the engine is out and the car sat for a long time I would also recommend putting some time into your spica fuel injection pump, read roadtrips bench check guide, suck some oil out of the logic section and make sure there is no fuel mixed with it. Make a dummy TA and set your nineteen thou, confirm your bell crank stops, etc while the engine is out too. Unless you have a burning desire to rebuild the engine because you just really want too, my view is the time, energy, money are better spent elsewhere. Like lightweight flywheel, change the synchros, rebuild front and rear suspension, new tires, 123 distributor, rebuilt spica pump if you have fuel in the oil.

There is a chance that with 170 cold on a not freshly rebuilt engine that you already have some kind of high compression piston installed or shaved head or something.

Cheers,
Hi, no, the engine is not torn yet. Sorry, but I cant remember oil pressure, I somehow remember that it looked good on the gauge, but that was in 2017 when I started the car.

I have one pump prepared and ready to install..

I do not have a burning desire, but dont have time to do things twice. By that I mean that if I will leave the bottom end as it is, and when I will put it in the car and it will smoke when I will start driving...well..I will not be happy :wink2:


I would say that this engine was never opened (the bottom end), and the pistons are original, the head was probably shaved, yes... Probably I should measure it. Maybe good compression is is because of carbon buildup?

The rest of work what you describe I have to do anyhow, car is 45 yrs old. Already bought a lot of parts...
 
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