am thinking of getting 40DCOEs for a conversion, am after some help with this if anyone has done it before.
i know you can buy the carbs and manifold from webcon but i dont have 1800 quid . was thinking of getting 3 x carbs 2nd hand.
how do you get rid of the electrics for the injectors and afm.
any help would be appreciated
325i to carbs help
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HairyScreech
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Short answer is don't.
You might get a few hp more but will lose torque, lose mpg and lose tractability.
Which is a pretty poor result for all the trouble of converting the engine back to a distributor or fitting a stand alone ignition controller.
A far better option would be to go for injection throttle bodies, possible a set knocked together from a bike or spending the money elsewhere on the engine and getting bigger gains.
You might get a few hp more but will lose torque, lose mpg and lose tractability.
Which is a pretty poor result for all the trouble of converting the engine back to a distributor or fitting a stand alone ignition controller.
A far better option would be to go for injection throttle bodies, possible a set knocked together from a bike or spending the money elsewhere on the engine and getting bigger gains.
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?
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m3.3.1 m20 thread - now running, chip needed - any volunteers?
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cecotto479
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But the noise.......triple 45s.....with trumpets.....
1981 E23 735i
1989 E30 325i Motorsport Convertible
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1989 E30 325i Motorsport Convertible
Bavarian Retro - Classic BMW Cars, Parts and Accessories - 12.5% discount for forum members on E30 parts - use voucher code "E30zone" at checkout
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HairyScreech
- Engaged to the E30 Zone
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- Joined: Sun Jan 21, 2007 11:00 pm
to me sound the same as throttles but less crisp on the transient, kind of like throttles with filters.
Perhaps i'm just a heathen.
Perhaps i'm just a heathen.
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&
I ran 40mm DCOE carbies on my 320/6 E21 with a 2.3L engine. Okay I didn't have to remove an existing electronic fuel injection (as the 320/6 is factory carburetted), but I did have to replace the awful carbie the car came with. The RHD E21's also have a bonus that the E30 doesn't and that is the location of the brake vacuum booster. The rear carbie will foul the E30 brake booster unless you some how modify it.
I agree with Hairy that replacing a perfectly good Motronic ECU with carbies is not the best idea, as it will introduce considerably more problems all for the sake of improving the sound (and on a smooth 6 cylinder like the M20, you don't get that great S14 or BDA style scream anyway). There is a reason car manufactures moved away from carbies, and why triple side draft setups were never popular factory setups - they are very difficult to keep in tune.. I was having to rebalance mine about 1 per month (my carbies were second-hand however and I would not expect such tuning would be necessary with "new" units).
Lastly I always felt that triple 40mm side draft carbies were far to big, as off throttle response was terrible, and required a very delicate throttle control when cold to prevent them stalling out (basically the butterfly would open - the air would very quickly flood into the valve intake and hit the closed intake valve and quickly stop - when the intake valve opened the air would not be moving, and as such there would be not fuel mixed with it - the engine would then go into stall). Once up and running at high rpm the response was great.
If you have decided this is what you want to do, then don't let anyone stop you (cars are nothing but a toy in the end, and what you do with it is your business and no one else's), but please consider 35mm carbies choked down to 30mm (or even 28mm) perhaps. This should give you better off idle response yet still maintain the good air velocity, and therefore crisp response, at higher rpm.
Lastly try Rowland manifolds in South Africa for M20 triple side draft manifolds. From memory it cost me AU$350 landed (in Australia). Not sure what that is in Pounds, but you may be able to build your own setup for much cheaper than the 1800 quid price you mentioned above.
I agree with Hairy that replacing a perfectly good Motronic ECU with carbies is not the best idea, as it will introduce considerably more problems all for the sake of improving the sound (and on a smooth 6 cylinder like the M20, you don't get that great S14 or BDA style scream anyway). There is a reason car manufactures moved away from carbies, and why triple side draft setups were never popular factory setups - they are very difficult to keep in tune.. I was having to rebalance mine about 1 per month (my carbies were second-hand however and I would not expect such tuning would be necessary with "new" units).
Lastly I always felt that triple 40mm side draft carbies were far to big, as off throttle response was terrible, and required a very delicate throttle control when cold to prevent them stalling out (basically the butterfly would open - the air would very quickly flood into the valve intake and hit the closed intake valve and quickly stop - when the intake valve opened the air would not be moving, and as such there would be not fuel mixed with it - the engine would then go into stall). Once up and running at high rpm the response was great.
If you have decided this is what you want to do, then don't let anyone stop you (cars are nothing but a toy in the end, and what you do with it is your business and no one else's), but please consider 35mm carbies choked down to 30mm (or even 28mm) perhaps. This should give you better off idle response yet still maintain the good air velocity, and therefore crisp response, at higher rpm.
Lastly try Rowland manifolds in South Africa for M20 triple side draft manifolds. From memory it cost me AU$350 landed (in Australia). Not sure what that is in Pounds, but you may be able to build your own setup for much cheaper than the 1800 quid price you mentioned above.
Cheers,
Michael.