Worn CGA3 Advice

Hi, I have a question and really hoping someone can help me out. My CGA3 engine drinks a little oil and I have a spare CGA3 that I am looking to put into my car.

My main concern is that I put the new engine in and then within a few months, it starts to drink the same amount of oil as my current one. If I put the replacement engine in, then the car WILL be put on a standalone ECU at the same time (most likely Omex or similar) and mapped on a rolling road.

So I guess my question is: how much of the engine wear is due to my current engine being pushed (8k rpm, ITB'S etc) and how much of it is down to a poor map (mine is currently on a chipped ecu and so its not a very accurate map at all, I am running without MAF and so it overfuels).

Opinions on facebook are that a poor map will always have more effect on damaging an engine rather than an engine being pushed, but it would be nice to get some opinions on here as well as I trust opinions on this forum way more than the stuff people put on facebook lol

Do you know where is the wear?

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Jorge_EETC said:

Do you know where is the wear?

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Yes I am pretty sure the piston rings are slightly worn. Compression used to be 125-130 across all 4 cylinders. After using some thicker oil, it is now 140 across cylinder 1,2 and 4, but cylinder 3 is still at 125psi.

It is only 1 litre of oil drank per 1000 miles but I'd rather it be less!

I think the amount of power you're making should be okish... Try mapping it properly, and raising oil pressure with the washers method...

But idk, but nevertheless, great vids bro

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i would say its the high rpm and carbon clogged rings
i did a limiter delete on my 1.0 white k11, and ragged it round the block,when i got back it was smoking bad
and when i stripped it i saw the rings were jammed stuck in their grooves
and the high rpm had squashed them more trapped

Jorge_EETC said:

I think the amount of power you're making should be okish... Try mapping it properly, and raising oil pressure with the washers method...

But idk, but nevertheless, great vids bro

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Thank you for the advice and support for the channel

frank said:

i would say its the high rpm and carbon clogged rings
i did a limiter delete on my 1.0 white k11, and ragged it round the block,when i got back it was smoking bad
and when i stripped it i saw the rings were jammed stuck in their grooves
and the high rpm had squashed them more trapped

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Thank you for your input. May consider getting the rev limit lowered to around 7.5k when we put the new engine in then

Are you thinking of going to work on the head? Dremel style

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Ihtisham Rauf said:

Thank you for your input. May consider getting the rev limit lowered to around 7.5k when we put the new engine in then

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the rpm will be ok as long as the rings are,nt coked up with carbon
mine would have been ok, the oil rings were clogged but they still scraped the oil off the bores
but the extreme rpm piston slap shoved the rings deeper into their grooves, and they did,nt scrape any more

frank said:

the rpm will be ok as long as the rings are,nt coked up with carbon
mine would have been ok, the oil rings were clogged but they still scraped the oil off the bores
but the extreme rpm piston slap shoved the rings deeper into their grooves, and they did,nt scrape any more

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I see. I reckon my bad ECU map causing the overfueling would have coked up my rings pretty bad. The new engine will get a full decoke and clean

Just need to minimise driving it on the new engine until its on the rolling road, which shouldn't be too much of a problem.

You probably know but nissan says it can drink 0.5l pre 1000miles IIRC and thats normal for them. Just a input

When it needs oil, I just top it up with cheap as chips 10/40 at £12/4 litres with no worries & get on with my life with no time wasting hassle messing about working on crud engines when still running ok.

plmval said:

When it needs oil, I just top it up with cheap as chips 10/40 at £12/4 litres with no worries & get on with my life with no time wasting hassle messing about working on crud engines when still running ok.

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Cheapests oils for the least life. The engines are very reliable and well made. Don’t see what you mean? Hope you have good experience with the oil as I’m sure 90% of us on here don’t / wouldn’t use it to clean an engine

Been running old banger Micras for 23 years on the cheapest multi grade I can find & two of them were on 156 K miles plus when I sold them on as good runners to the next punter.

That’s the facts of my experience & suggests longevity is as much about how you treat & drive it as it was designed to be used rather then just what oil ?

plmval said:

Been running old banger Micras for 23 years on the cheapest multi grade I can find & two of them were on 156 K miles plus when I sold them on as good runners to the next punter.

That’s the facts of my experience & suggests longevity is as much about how you treat & drive it as it was designed to be used rather then just what oil ?

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Yea just saying personally never had a good experience with it and customers that bring in their cars with cheap oil always have engine problems is all. Just sharing my experience mate

plmval said:

When it needs oil, I just top it up with cheap as chips 10/40 at £12/4 litres with no worries & get on with my life with no time wasting hassle messing about working on crud engines when still running ok.

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Mine is a project car rather than just a crud engine car. I find there's two categories of Micra owners in the UK.

1. Owners who have them as project cars
2. Owners who have them as workhorses/banger racers etc

Nothing wrong with either (I've stripped a few Micra's and send them off for banger racing without a care lol) but your approach wouldn't work well with my project Micra, but thanks for the suggestion.

Ihtisham Rauf said:

Mine is a project car rather than just a crud engine car. I find there's two categories of Micra owners in the UK.

1. Owners who have them as project cars
2. Owners who have them as workhorses/banger racers etc

Nothing wrong with either (I've stripped a few Micra's and send them off for banger racing without a care lol) but your approach wouldn't work well with my project Micra, but thanks for the suggestion.

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Seen your vids (guessing its you) and your car both amazing. Why not SR20 or big engine i must ask?

SashaKing said:

Seen your vids (guessing its you) and your car both amazing. Why not SR20 or big engine i must ask?

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Ha thanks for the support! SR20 makes the insurance sky high for me currently so sticking with trying to get as much out of the CGA3 for now while on a reasonable budget

Are there tricks to loosen a piston ring without opening the engine? Would compression restore additive have a chance? For the engine, I would not replace it too soon, cheap oil and make it scream some more to learn if cylinder number 3 actually will give up for real. I am not convinced your engine went bad. That needs a lot of abuse. Also for waste of gasoline, I can't imagine it would do much past the piston ring.

And for the oil pressure, are you sure there is not something blocked by modification or that you have under or over pressure somewhere in the system? Also if the engine doesn't drip oil on the road it does not mean it can loose it anyway. Is your engine that dry everywhere?

And if you happen to have a spare engine, I would abuse the one you have there a bit more to learn from it. Also while having one lower compression is something to worry about I think but I should look that up to be sure cylinder 3 is just within specification?

richardwbb said:

Are there tricks to loosen a piston ring without opening the engine? Would compression restore additive have a chance? For the engine, I would not replace it too soon, cheap oil and make it scream some more to learn if cylinder number 3 actually will give up for real. I am not convinced your engine went bad. That needs a lot of abuse. Also for waste of gasoline, I can't imagine it would do much past the piston ring.

And for the oil pressure, are you sure there is not something blocked by modification or that you have under or over pressure somewhere in the system? Also if the engine doesn't drip oil on the road it does not mean it can loose it anyway. Is your engine that dry everywhere?

And if you happen to have a spare engine, I would abuse the one you have there a bit more to learn from it. Also while having one lower compression is something to worry about I think but I should look that up to be sure cylinder 3 is just within specification?

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Unsure whether rings can be loosened without opening engine. I'm not really fond of additive after hearing a few horror stories of people using them and then wrecking their engines. The engine is pretty dry everywhere else although it would be nice to know the compression specs range

Ihtisham Rauf said:

Unsure whether rings can be loosened without opening engine. I'm not really fond of additive after hearing a few horror stories of people using them and then wrecking their engines. The engine is pretty dry everywhere else although it would be nice to know the compression specs range

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This is the original compression values according to heynes manual

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I would skip the higher then usual compression and compare cylinder 3 compression to minium stated.

There is quite a difference between standard and minimum. I still believe that cylinder 3 is keeping up and car races like mad like always?

I would take plugs, take the three other plugs and compare it with cylinder 3. The difference there will give clues. If all four are same, it wil give clue also.

Another point, spending 15 coins on an additive to see what happens is cheap in the cirucumstances you have there (full ITB, ecu upped, etc) however that stuff might give dissapointing results and there is no real way without tearing up the engine to tell if the stuff worked well or did something.

So the additive itself has to be questioned, but how?

On the other hand, besides spark plugs, #1 reason for compression loss (I assume here you had notable #3 compression loss *after* ITB'ing it (with other 'party mode' settings (your quite upgraded engine), ah well, I would like to see some spark plugs.

I would race the little engine to smithereens with having donor engine. Again, if compresson cylinder 3 is high enough it should not matter much. How you've gotten such high comression on the other cylinders, I wonder how that is possible.