Turbo Engine rebuild 20HC85

[Jeff Turbo]

Hi Jeff, no wonder it was losing power when the turbo started building pressure… haha. I’ll replace the pump with an EFI one I have.
You think it’s dangerous to use an ECU from a naturally aspirated engine on a turbo engine, right?
The car was pulling quite well, without going over 3500 rpm because I was being cautious. Once I change the fuel pump it should run even better. I think the fact that the map doesn’t retard the timing enough could cause knocking. I’m using a turbo carburetor.
Do you know anyone with experience working with these ECUs? Someone who has reprogrammed them?

It won't adjust the timing when you boost so you might do damage to the engine as the timing will be wrong. It doesn't do it any good i'm afraid. Do you have an ECU mapping service near where you live as they can possibly remap your ecu on a rolling road. The turbo kicks in about 2500-3000 revs
I saw your post on facebook but you'll get 5 different answers on that and only one correct, Danial Pyke knows all about turbos and is correct on his post there. Facebook will give you quick answers but not many will be correct

[Juanmacandel]

Hi Jeff, no wonder it was losing power when the turbo started building pressure… haha. I’ll replace the pump with an EFI one I have.
You think it’s dangerous to use an ECU from a naturally aspirated engine on a turbo engine, right?
The car was pulling quite well, without going over 3500 rpm because I was being cautious. Once I change the fuel pump it should run even better. I think the fact that the map doesn’t retard the timing enough could cause knocking. I’m using a turbo carburetor.
Do you know anyone with experience working with these ECUs? Someone who has reprogrammed them?

[Jeff Turbo]

The fuel pump for a normal asperated carb model is different to an efi/turbo model and isn't up to the job. Efi and turbo fuel pumps are the same, a range rover V8 fuel pump in the same and with the correct terminals but sometimes you have the swap over the connections as they can be wired the wrong way round, easy job though. The car won't boost if you've added the turbo etc as the ECU isn't the correct one and won't adjust the timing as it boosts. Can't remember now but you do have a turbo carb on the car and not a normal carb ?

[Juanmacandel]

Yesterday I was finally able to take the car out for a spin. Right now I'm using the ERIC ECU for the naturally aspirated carburetor because I haven't found a solution. Is it dangerous to use the car with this ECU while it's turbocharged? While I was taking a short drive, the car bogged down and even shut off as if it had no fuel. I stopped, turned the key again and it started. It behaved like this for a while when I once installed a very restrictive fuel filter, but I’m not using one now. Could it be because of the fuel pump? I'm using a fuel pump for a naturally aspirated carburetor. Is there a specific one for turbo?

[Jeff Turbo]

hi jeff,
my wiring loom has it. my montego is from 1992.so maybe it’s easier to do a reprogramming? do you know where i can find some documentation about it?

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No sorry I don't, my manuals don't cover the internals of an ECU, diagnostic plug is in the wiring diagram on page 315 as number 110

[Juanmacandel]

hi jeff,
my wiring loom has it. my montego is from 1992.so maybe it’s easier to do a reprogramming? do you know where i can find some documentation about it?

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[Jeff Turbo]

Late mg montegos had a diagnostic plug in, early didn't. I assume it can be added to the wiring loom but that's way out of my knowledge and skill set

[Juanmacandel]

Sorry, Jeff — I meant whether a special cable is needed to communicate with the ECU and download the data, or if it’s necessary to desolder a chip to read the memory.

[Jeff Turbo]

The car currently runs only with the ERIC ECU, so that’s not a problem. I imagine it does, though — if that’s the case, do you know where I could get it?

A programmer might be able to produce a be-spoke one for your car but it won't be cheap. Have you asked any company in your country or nearer you if they can do this?
I have asked a friend of mine if he has a turbo engine loom in his spares but it will be the older type if he has one. Will get back to you

[Juanmacandel]

The car currently runs only with the ERIC ECU, so that’s not a problem. I imagine it does, though — if that’s the case, do you know where I could get it?

[Jeff Turbo]

Do you know if it’s possible to reprogram an ERIC ECU to load a turbo map?
Would the pressure sensor still work, or would it have to be one that can read above atmospheric pressure?

Any good ECU programmer should be able to do that for you but they would probably need the car there running so they can adjust what needs to be done on a rolling road I should imagine

[Juanmacandel]

Do you know if it’s possible to reprogram an ERIC ECU to load a turbo map?
Would the pressure sensor still work, or would it have to be one that can read above atmospheric pressure?

[Juanmacandel]

Hi Jeff, I think this ECU would be the best option to get the car running. Unfortunately, I can’t find this ECU. The page you shared told me they don’t have it in stock, and the price for a rebuilt one is $245 plus taxes. The problem is, I don’t even have one, hehe

[Jeff Turbo]

Hi Jeff,

I’m checking the page you sent me to see if I can get one. In the meantime, I’m also looking for a second-hand unit. If neither option works, I might go straight to the final stage of this engine project, which is adapting EFI injection with a programmable ECU.

If they have the correct part that would be better. You've spent this much on it so it's not a lot more. Once fitted you should only may have to rewire a few things to make it work properly

[Juanmacandel]

Hi Jeff,

I’m checking the page you sent me to see if I can get one. In the meantime, I’m also looking for a second-hand unit. If neither option works, I might go straight to the final stage of this engine project, which is adapting EFI injection with a programmable ECU.