inlet manifolds
Moderator: martauto
hi, can anyone point me in the direction of anyone who makes inlet manifolds for sidedraft dcoe45 carbs for a m20b20,m20b25 engine please, been looking on the net and cant find anything. might mean you cant get them, but someone here may know.cheers scott.
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HairyScreech
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Can I ask what your trying to gain from 45s?
If its for a historic race class then fair enough, there are a few out there and they do come up on ebay occasionally.
If its for road use then they rarity is related to the fact they are shit.
45s are too big for an engine with ~400cc per cylinder. 40s would be a better call.
A side draft webber manifold will lose torque everywhere with minimal power gain and the bad bit is the inlet valve size and intake port.
Going back to carbs on a fuel injected car is a huge step backwards, FI and carbs give equal full throttle performance but carbs give significantly worse part throttle operation in terms of economy and torque due to poor air/fuel metering and poor atomisation.
You need something to control the Ignition, which tends to mean a distributor, another downgrade.
A side draft tripple carb set up is going to be drawing nothing but hot air without a custom plenum set up (try fitting that in with sensible length inlet runners)
For the cost of a tripple webber set up you could have +1 intake valves fitted to the head, and likely a quick and dirty 2.8 bottom end thrown in, a much better upgrade that would be faster everywhere.
If your management is dead/not very good why not look at using the M50NV set up a few people have done in the past.
Coil on plug, no dizzy/rotor, MAF instead of AFM, lambda control, better ECU, better injectors, better economy and throttle response, torque and power gains debatable but certainly no losses.
All in all still easier than a DCOE conversion.
If its for a historic race class then fair enough, there are a few out there and they do come up on ebay occasionally.
If its for road use then they rarity is related to the fact they are shit.
45s are too big for an engine with ~400cc per cylinder. 40s would be a better call.
A side draft webber manifold will lose torque everywhere with minimal power gain and the bad bit is the inlet valve size and intake port.
Going back to carbs on a fuel injected car is a huge step backwards, FI and carbs give equal full throttle performance but carbs give significantly worse part throttle operation in terms of economy and torque due to poor air/fuel metering and poor atomisation.
You need something to control the Ignition, which tends to mean a distributor, another downgrade.
A side draft tripple carb set up is going to be drawing nothing but hot air without a custom plenum set up (try fitting that in with sensible length inlet runners)
For the cost of a tripple webber set up you could have +1 intake valves fitted to the head, and likely a quick and dirty 2.8 bottom end thrown in, a much better upgrade that would be faster everywhere.
If your management is dead/not very good why not look at using the M50NV set up a few people have done in the past.
Coil on plug, no dizzy/rotor, MAF instead of AFM, lambda control, better ECU, better injectors, better economy and throttle response, torque and power gains debatable but certainly no losses.
All in all still easier than a DCOE conversion.
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822
m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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Grrrmachine
- E30 Zone Wiki / Team Member

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Still waiting for your writeup on thisHairyScreech wrote:If your management is dead/not very good why not look at using the M50NV set up a few people have done in the past.
'89 325i Touring | Touring Resto Thread | In-Dash Screen install
- DarioStraightSix
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- Location: Italy (north east)
Some people did this mod on E21s 320\6 ,the carbured version of the M20B20. Back in the 80s,here in Italy,there was a car modder that did a complete kit for the M20B20,that guy was Romeo Ferraris. The kit was made with 3 weber 40 carburators. There was even the option of a modified camshaft available. The Ferraris intake manifolds are something very very rare nowdays.
Anyway i've seen some other E21s with the triple sidedraft around the world. Some videos :
The noise is really really awesome! An onboard video :
And,yeah,an E30 with an M20B25 stroker on carbs!!
......anyway,have a look,absolutely not cheap,but they did it :
http://www.webcon.co.uk/shopexd.asp?id=15128
Anyway i've seen some other E21s with the triple sidedraft around the world. Some videos :
The noise is really really awesome! An onboard video :
And,yeah,an E30 with an M20B25 stroker on carbs!!
......anyway,have a look,absolutely not cheap,but they did it :
http://www.webcon.co.uk/shopexd.asp?id=15128
James
'91 325i Sport
'93 318i touring 16v
'91 325i Sport
'93 318i touring 16v
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steve_k
- E30 Zone Team Member

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so am i!!!Grrrmachine wrote:Still waiting for your writeup on thisHairyScreech wrote:If your management is dead/not very good why not look at using the M50NV set up a few people have done in the past.
waiting to get a list together of exactly which parts i need & what years to & from.
c'mon dude, this could be pretty big for you
if it's got t*ts or wheels it's bound to be trouble...............prove me wrong.
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
getting oral sex off an ugly person is like rock climbing.....don't look down ;)
hi, thanks for the replies so far, the main reason was just to be different, everyone up my way just throw a more modern engine in for power gains, and know body seems to tune the 2L engine leaving the capacity the same, there may be good reasons for not. i had a mk1 golf 20 years ago that i put a 16v in on 45's and it was really good. i myself am new to bmw's and the car i have is a pre facelift 320i, 1995, so i'm just looking at what to do to it. i'm not looking for loads of power, but more than what i have, and want to do something different. scott.
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Grrrmachine
- E30 Zone Wiki / Team Member

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The reason people put more modern engines in is because the M20B20 is pretty much untuneable.
Either enjoy it for what it is (a silky cruiser that's perfect for country drives) or do something silly like supercharge it. But carbs really aren't the way to go.
Either enjoy it for what it is (a silky cruiser that's perfect for country drives) or do something silly like supercharge it. But carbs really aren't the way to go.
'89 325i Touring | Touring Resto Thread | In-Dash Screen install
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Speedtouch
- Old Skooler

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A prefacelift will be something like 1985, not 1995. These had the L-Jetronic analogue injection system, and one good upgrade is to convert to the facelift Motronic 1.3 engine management system, which will net you an extra 4 bhp in standard form, and can be chipped for a bit more.
http://www.e30zone.net/e30zonewiki/inde ... tronic_1.3
http://www.e30zone.net/e30zonewiki/inde ... tronic_1.3
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
viewtopic.php?f=6&t=279421
Inlet manifolds are available from Rowlands in South Africa. I have a set to put throttle bodies on, not carbs.
The finish on them is, ahem, poor. The finish inside is the same ! There is a fair bit of work to make them fit, and the mounting threads are not always in the correct place. I can post pictures if you want to go further.
The finish on them is, ahem, poor. The finish inside is the same ! There is a fair bit of work to make them fit, and the mounting threads are not always in the correct place. I can post pictures if you want to go further.
www.racehead.com.au have a quality CNC manifold that wont screw the flow into the cylinder head320smithy wrote:Inlet manifolds are available from Rowlands in South Africa. I have a set to put throttle bodies on, not carbs.
The finish on them is, ahem, poor. The finish inside is the same ! There is a fair bit of work to make them fit, and the mounting threads are not always in the correct place. I can post pictures if you want to go further.
E30 325is with M20B31
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HairyScreech
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You won't get a M50NV version from me, I have a TU set up.steve_k wrote:so am i!!!Grrrmachine wrote:Still waiting for your writeup on thisHairyScreech wrote:If your management is dead/not very good why not look at using the M50NV set up a few people have done in the past.
waiting to get a list together of exactly which parts i need & what years to & from.
c'mon dude, this could be pretty big for you
NV can be found here: http://www.e30tech.com/forum/showthread.php?t=63504
The TU has a slightly more sophisticated ECU and a better MAF sensor, along with a VANOS actuator.
Wiring is similar and a lot of the hurdles are the same.
Have changed insurance companies now and have garage access again so started to tinker with it again, the only thing stopping me getting on with it is free time now, but my fuel economy to work is pushing me to get on with it. (22mpg due to traffic/constant part throttle)
2.8 development thread http://www.e30zone.net/modules.php?name ... c&t=170822
m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
m3.3.1 m20 thread - now running, chip needed - any volunteers?
http://www.e30zone.net/modules.php?name ... =viewtopic&
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Grrrmachine
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