in turboing an m20b20.
I've been going through various options for my E30 over the last few months and have come up with around 3 options.
1 - 2.7 conversion with b20 head.
2 - m20b25 swap, easy as pie but a bit meh.
3 - Super/turbo my current engine.
My favourite was the 2.7 conversion, but I am now unsure and am wondering about just doing some sort of FI on my current engine, aswell as a head rebuild. My reasoning is that I could do all of the work with the engine block in situ, it'd be a realitivly easy plumbing/electrical job and it would be fairly easy to swap the whole lot over if I did do the 2.5/2.7 conversion, or did something completely different.
What are your thoughts on this? And what sort of boost and power gains could I expect on stock internals?
I wont actually be able to start work until the middle of next year, which is a bugger as I have been thinking far too much...
Thanks for any advice.
Is there any point....
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gooner1
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godinman, so many ponderables in your question.
Budget. Ultimate aim of any conversion. Your skills in carrying out the work.
If the ultimate goal is pure power, then you will probably soon grow tired of the 2.7 route.
Not sure what the stock m20b20 internals are capeable of handling, but seem to remember
the m20b25 internals can handle 300bhp fairly well.
Others far more qualified to answer your queries will no doubt be along to help fairly soon.
Budget. Ultimate aim of any conversion. Your skills in carrying out the work.
If the ultimate goal is pure power, then you will probably soon grow tired of the 2.7 route.
Not sure what the stock m20b20 internals are capeable of handling, but seem to remember
the m20b25 internals can handle 300bhp fairly well.
Others far more qualified to answer your queries will no doubt be along to help fairly soon.
I suppose I should have mentioned a budget, it's difficult, sitting here now I wouldn't want to spend more than 2-3k as much more and I might as well just get a faster car, except that I really like E30...
Aim - Reliable, more powerful car, that's drivable so I'd like some low-down power, not just after 5k or something. It's basically a weekend car as I have a works van so doesn't need to be ultra refined or cheap to run. I'd like a project I can learn from, and improve as I go along, which sort of points to the FI route..
Power, anything over 250bhp would be plenty!
Cheers, for the reply.
Aim - Reliable, more powerful car, that's drivable so I'd like some low-down power, not just after 5k or something. It's basically a weekend car as I have a works van so doesn't need to be ultra refined or cheap to run. I'd like a project I can learn from, and improve as I go along, which sort of points to the FI route..
Power, anything over 250bhp would be plenty!
Cheers, for the reply.
If you are planning on turboing the 2.0 too 270hp then you are going to need about 15psi boost.
In doing so you should highly consider buying the bits so that you can convert it to a 2.7 or 2.5 later and still maintain the 15psi (340-360hp). It should be doable using stock headgasket and headbolts. and most likely stock clutch as well.
If you plan on doing this over time then the FI route is ideal.
I reccomend for you to learn from this is get your tuning solution sorted out. Nothing beats having the ecu or dme ready for more power and the ability to do so without more and more money at every turn.
So look into getting a standalone or get the bits to be able to tune the stock ecu.
So many people throw together a shopping list and in doing so the project becomes massive to handle in short time, rather my suggestion is to figure out the individual projects and accomplish one at a time. You gain NOTHING from buying a turbo until you need one.
In doing so you should highly consider buying the bits so that you can convert it to a 2.7 or 2.5 later and still maintain the 15psi (340-360hp). It should be doable using stock headgasket and headbolts. and most likely stock clutch as well.
If you plan on doing this over time then the FI route is ideal.
I reccomend for you to learn from this is get your tuning solution sorted out. Nothing beats having the ecu or dme ready for more power and the ability to do so without more and more money at every turn.
So look into getting a standalone or get the bits to be able to tune the stock ecu.
So many people throw together a shopping list and in doing so the project becomes massive to handle in short time, rather my suggestion is to figure out the individual projects and accomplish one at a time. You gain NOTHING from buying a turbo until you need one.
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Ant
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^^^^ best advice I've seen on here for a LONG time Gunni 
B20 has an extra 4mm of clamping meat on the bores, no issue boosting that one but as stated, the ECU is the 1st thing to buy, not the last........
B20 has an extra 4mm of clamping meat on the bores, no issue boosting that one but as stated, the ECU is the 1st thing to buy, not the last........
Product Development and Endurance for Delphi.
Original performance chips, original works not unlicensed copies
Email FTW
Original performance chips, original works not unlicensed copies
Email FTWThat seems like bloody good advice, thanks:)
I'll get researching megasquirt, luckily my mate has it running his 205, so I'll pick his brain..
So you're saying I could running fairly high pressure on stock internals? I'll be hopefully getting a second 2.0 head to have a tinker with (they're dirt cheap), so that can entertain me hopefully until I can afford to do some serious work.
I'll get researching megasquirt, luckily my mate has it running his 205, so I'll pick his brain..
So you're saying I could running fairly high pressure on stock internals? I'll be hopefully getting a second 2.0 head to have a tinker with (they're dirt cheap), so that can entertain me hopefully until I can afford to do some serious work.
There is nothing limiting you as the pistons and rods can easily handle that pressure, that pressure is also not to high for the headbolts.
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TouringTash
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If the block is left in situ would mean that the oil pump will stay as is. Not sure if this would be an issue with an M20 donk but personally I would be replacing components like this if I was looking to add more stress to an engine.
My choice would be to correctly build a 2.7 ie. open up the bottom, inspect and measure all the moving parts before bolting the head and bits. This would give you a sorted platform to then look at adding a turbo without the waiting stages whilst funds become available. And has the added bonus of giving you more power and then even more power.
My choice would be to correctly build a 2.7 ie. open up the bottom, inspect and measure all the moving parts before bolting the head and bits. This would give you a sorted platform to then look at adding a turbo without the waiting stages whilst funds become available. And has the added bonus of giving you more power and then even more power.
318i Touring
Can't the pump be replaced with the engine in situ? I'd probably fit the 325i oil cooler at some point also..
I see what you're getting at, but I kind of like the 2.0 engine. I'm thinking if I fitted shrick arms and springs I could probably get it revving quite well (due to the short stroke?), and then with the addition of a well managed turbo I'd probably have a rather nice little screamer going:) - still hopefully maintaining some low down grunt tho!
The problem is the time factor, I can't do anything at all for a while and can't stop myself thinking about it all!
I see what you're getting at, but I kind of like the 2.0 engine. I'm thinking if I fitted shrick arms and springs I could probably get it revving quite well (due to the short stroke?), and then with the addition of a well managed turbo I'd probably have a rather nice little screamer going:) - still hopefully maintaining some low down grunt tho!
The problem is the time factor, I can't do anything at all for a while and can't stop myself thinking about it all!
While cams and turbo sounds like a win win, the 731 head is not lacking in flow so you´d sooner be able to bust open your bottom end before the top end suffers seriously.godinman wrote:Can't the pump be replaced with the engine in situ? I'd probably fit the 325i oil cooler at some point also..
I see what you're getting at, but I kind of like the 2.0 engine. I'm thinking if I fitted shrick arms and springs I could probably get it revving quite well (due to the short stroke?), and then with the addition of a well managed turbo I'd probably have a rather nice little screamer going:) - still hopefully maintaining some low down grunt tho!
The problem is the time factor, I can't do anything at all for a while and can't stop myself thinking about it all!
also cams and low down grunt with a decent turbo is almost impossible.
Yes, I think I possibly got carried away there. I reckon plan BMk2.5 is a goer.
1) Purchase new 2.0 head for playing and entertainment, replace existing head as it does have a few problems (some case hardening gone somewhere as I can't get the valve clearances low enough on a few).
2) Wait.
3) Implement MegaSquirt fuel and spark system.
4) Tinker.
5) Install turbo setup.
6)Tinker.
That should fill the next 3 years with any luck.
Thanks for the help, I'll repost when I've got some exciting news on a 2.0 head.
1) Purchase new 2.0 head for playing and entertainment, replace existing head as it does have a few problems (some case hardening gone somewhere as I can't get the valve clearances low enough on a few).
2) Wait.
3) Implement MegaSquirt fuel and spark system.
4) Tinker.
5) Install turbo setup.
6)Tinker.
That should fill the next 3 years with any luck.
Thanks for the help, I'll repost when I've got some exciting news on a 2.0 head.
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TouringTash
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I think it can be done but would be a pita with a little extra hot sauce.godinman wrote:Can't the pump be replaced with the engine in situ? I'd probably fit the 325i oil cooler at some point also..
The problem is the time factor, I can't do anything at all for a while and can't stop myself thinking about it all!
As for plenty of time to research goes more time now should mean less visits from Mr Cockup later on.
318i Touring
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TouringTash
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Have a good 731 from a 137K m20b20 with slushbox stuck on the back.
318i Touring
I say go for 2.0 turbo if you want less than 300bhp.
I've had a 2.7 which cost about £2000 to build myself. The car was faster with the 2.7 than the 2.5 but but not by much. But I did have a fully rebuilt engine and no worries of anything breaking.
I've currently got a M30 3.5. And this is tank engine, heavy and boring to driving. Not much better than a 2.7.
I've had a M40 1.8 that I turbo'd myself for about £1200. This was one of the most fun cars I've ever drove. It had about the same power of the other engines I've had but it was economical, fast, thrilling and if the engine went wrong I could of got another for £50-£100.
Before I put the 3.5 in my current car it had a 2.0 engine in that I was going to turbo and I now regret that I didn't do it.
If you decide to go for megasquirt, I'd recommend building yourself. I found it easy and it work first time for me, didn't even test it, the instructions are really good. Also building yourself give you an idea of what each part does and helps you figure out any problems you might have or upgrades you need to make. I built my for about £200 in a motronic case, so it was plug and play incase it needed to be removed.
I've had a 2.7 which cost about £2000 to build myself. The car was faster with the 2.7 than the 2.5 but but not by much. But I did have a fully rebuilt engine and no worries of anything breaking.
I've currently got a M30 3.5. And this is tank engine, heavy and boring to driving. Not much better than a 2.7.
I've had a M40 1.8 that I turbo'd myself for about £1200. This was one of the most fun cars I've ever drove. It had about the same power of the other engines I've had but it was economical, fast, thrilling and if the engine went wrong I could of got another for £50-£100.
Before I put the 3.5 in my current car it had a 2.0 engine in that I was going to turbo and I now regret that I didn't do it.
If you decide to go for megasquirt, I'd recommend building yourself. I found it easy and it work first time for me, didn't even test it, the instructions are really good. Also building yourself give you an idea of what each part does and helps you figure out any problems you might have or upgrades you need to make. I built my for about £200 in a motronic case, so it was plug and play incase it needed to be removed.
That's rather interesting, so you used most of the original loom then? I think i will be going for a turbo setup, it sound like there are lots of tinkering opportunities to keep me entertained, just trying to source a good head to sort out.
Gunni, i spoke to the lad who has megasquirt running on his 205 and apparently it was actually you who helped him get it going? You know Ken? Small world if so!
Gunni, i spoke to the lad who has megasquirt running on his 205 and apparently it was actually you who helped him get it going? You know Ken? Small world if so!
Kenny Cliffe 
It IS a small world indeed.
Yea I helped him out a bit but he did do most of it himself. I just did a little bit of tuning and such.
It IS a small world indeed.
Yea I helped him out a bit but he did do most of it himself. I just did a little bit of tuning and such.
The link below is what I followed to put it in a standard ecu case.
http://wiki.diyefi.co.uk/index.php?titl ... Conversion
http://wiki.diyefi.co.uk/index.php?titl ... Conversion
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TouringTash
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Sorry bud head not for sale. I suspect the head will require a rebuild due to a suspected oil starvation within the engine somewhere and I wouldn't want to sell anything that I don't have faith in.
318i Touring
No worries TT:)
Chu, that's brilliant, thanks.
Gunni, very weird! I know ken well, went to school with him and worked with him for a few years. Good lad, and he's just down the road so I shall be annoying him asking for advice for a while:)
Chu, that's brilliant, thanks.
Gunni, very weird! I know ken well, went to school with him and worked with him for a few years. Good lad, and he's just down the road so I shall be annoying him asking for advice for a while:)
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daimlerman
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Of course the pump can be replaced with the engine in place!godinman wrote:Can't the pump be replaced with the engine in situ?
You just need to remove the sump first,to slide the sump out you need to unbolt the pump and let it drop into the sump bowl...it's going back that's the PITA,drop one bolt into the sump whilst locating the bloody pump and you have to start all over again.....
Youth is wasted on the young.