Conversion from SR18DE to SR20DE

[PreseaLover]

Hi Folks,

The car is a an automatic Bluebird U13 Arx and it has driven 205k km's already, and I'm seeing signs of engine trouble like plugs getting impacted with oil and burns out, engine knocking even though the distributor is set to retard (max), and issues with idle stabling. However the pickup and speed hasnt reduced. So I'm guessing in another 15k to 20k km's im expected to have to do an engine overhaul or replace it. So I'm thinking, instead of doing the same SR18 engine again, to replace it with the SR20DE. But before prepping for this I need to know all the details as to what I should expect to do and keep in mind when I do the swap. Following are my questions:

1. Will the brackets/mounting fit the SR20DE engine without a problem or do I have to do new mounting adjustments also or is it just a direct fit? is it the same engine design?

2. Do I only have to change the ECU, Gearbox when I do the engine swap or are there any more items that needs to go in?

3. Should I be worried about suspension too? Like should I be upgrading the suspension too to fit the SR20? 

4. What are the CONS? 

[iRage]

1. Main difference between the SR20 and SR18 block is the bore size. The body, thus the mounting ancilliaries for both, should and are the same. Only thing I would look out for is to make sure both engines are of the same generation of the SR. (Parts catalog confirms this as it has the same part numbers for both)

2. Doesn't the SR18 and SR20 Bluebird come with the same FL4F03A gearbox ? I am pretty sure even things like the alternator and compressors are also the same. Again, just make sure if is of the same SR generation. I would also look in to upgrading the cooling system. Also, some variants of the SR20 comes with a larger brake booster and master pump. This is more specific for the grade levels than the engine so it is up to you to go through with it or not (same with the suspension).

3. Suspension for the SR18 and SR20 are also the same (parts catalog confirms it). Only time it changed seem to have been with different grades (sportier trim lelvel having slightly harder springs) and when there was a facelift (the part nubmers have changed but I can't see what has actually changed).

4. Cons : If done by a maka baas you will have a pile of very expensive metal junk on your hands. Then you ahve to go through the hassle of dealing with the RMV. Fuel consumption might be a bit on the lower side but I am sure it won't be by that much once you get used to driving it and not be heavy footed.

 

[PreseaLover]

Thanks for your feedback irage.. this looks promising then

[matroska]

ooh oooh this is exciting.

There's actually a healthy number of SR20's around at parts shops and the like. 

[matroska]

On 11/25/2021 at 6:59 AM, PreseaLover said:

2. Do I only have to change the ECU, Gearbox when I do the engine swap or are there any more items that needs to go in?

btw usually gearbox-ecu-engine comes as a set might be less hassle to just get the entire set together. But as Irage said the old gearbox ecu combo might be compatible as well. 

[Ruslan]

I Would say, save the hassle and get both and replace and be done with it. not sure what might come after replacement of the old gearbox with wear and tear... @PreseaLover please share pics and details if your going ahead man. its pretty rare these type of builds / conversion in AL these days

[PreseaLover]

One question. Currently the idle stable issues I'm having in my car which none of the mechanics were able to diagnose, they suspect its either an air issue or an electrical issue. So lets say, when I swap the SR18 with the SR20, do you think the electrical components get swapped too, so that this issue I have will also be gone away? or the electrical components will stay the same in the car? 

Adding to this, earlier when my car ignition was set to advance there was knocking. Then I retarded the ignition and the problem went away.. Now again even though the ignition is in retard, the knocking is back. So do you think the engine wearing out is just around the corner? A plug also got burned within 3 weeks of replacement. 

Edited November 28, 2021 by PreseaLover

[iRage]

1. Whether you retain the sensors and other electronics depends on what you buy. Some engines pretty much come with all electronics in tact whilst some don't. In some cases, like with the 4A_GE, even if the engine came with all the electronics the engine sellers strip them off and sell them seperately (due rarity hich has pushed their prices up). So you should try to buy one with everything already in place.

2.Hmmm.... It does seem like your engine will need some significant work done soon. 

[PreseaLover]

53 minutes ago, iRage said:

1. Whether you retain the sensors and other electronics depends on what you buy. Some engines pretty much come with all electronics in tact whilst some don't. In some cases, like with the 4A_GE, even if the engine came with all the electronics the engine sellers strip them off and sell them seperately (due rarity hich has pushed their prices up). So you should try to buy one with everything already in place.

2.Hmmm.... It does seem like your engine will need some significant work done soon. 

I see.. thanks irage. Hope to at least run this for 2 years (20k km's) before I could save some money for the conversion project. 

[iRage]

7 hours ago, PreseaLover said:

I see.. thanks irage. Hope to at least run this for 2 years (20k km's) before I could save some money for the conversion project. 

Don't make any solid decisions just yet....do some costings and see whether it makes sense to fix the current engine....