Hi,
I'm fitting MJ to a 1330 A series (Kent 260 cam) that is fitted with a 1 3/4" SU HIF carb. I think I'm right in thinking that the standard vac take-off is unsuitable for MAP and that I'll have to drill the manifold and fit one or two take-offs.
Am I right in thinking that two would be better? What volume of plenum would you recommend?
Rich
A Series Vacuum Plenum size?
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NITROPIXIE
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Your correct the standard take off is not really usable, the one on the back of the carb behind the dashpot (manifold side). This should be blanked off. The reason it can't be used is when the butterfly is fully closed, the hole is on the atmospheric side so does not have any of the vacuum going to the MAP sensor.
Either tap the manifold or buy one with it, or you can buy a sandwich plate with one attached or even tap that yourself http://minispares.com/Product.aspx?ty=pb&pid=36947 . You don't need two, just one for the Map sensor, unless you want one for a brake servo???
As for size of vacuum reservoir, i'm just about to set a series of tests to workout a decent size using a syringe as a variable vacuum reservoir and watch the smoothing affect on the compter software. You can experiment with this but it doesn't need to be too big, say no bigger than a 'D' size battery.
Hope that helps
Either tap the manifold or buy one with it, or you can buy a sandwich plate with one attached or even tap that yourself http://minispares.com/Product.aspx?ty=pb&pid=36947 . You don't need two, just one for the Map sensor, unless you want one for a brake servo???
As for size of vacuum reservoir, i'm just about to set a series of tests to workout a decent size using a syringe as a variable vacuum reservoir and watch the smoothing affect on the compter software. You can experiment with this but it doesn't need to be too big, say no bigger than a 'D' size battery.
Hope that helps
1310 A-series Mini, lightened and built myself. V4 board and loving it
Rasputin22 - The Mini Forum
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Megajolt repair for the UK available
Rasputin22 - The Mini Forum
Rasputin22 - MK1 Golf Forum
Megajolt repair for the UK available
the point of the vacuum plenum is to even out the vacuum pulses on a motor with >1 individual intake runners. if you have one single throttle carburetor, then you dont need the vacuum reservoir at all.
as for tapping the inlet manifold, i used 1/8" brass tube (ie 3.1mm OD) and drilled a 3mm hole into the manifolds. i put a light smear of epoxy glue in the hole, and tapped the tube in for perfect interference fit.
alexander.
as for tapping the inlet manifold, i used 1/8" brass tube (ie 3.1mm OD) and drilled a 3mm hole into the manifolds. i put a light smear of epoxy glue in the hole, and tapped the tube in for perfect interference fit.
alexander.
I have just fitted MJ to the 1380 A-series in my Midas. I used the original distributor vacuum take-off on the HIF 44 for the MAP sensor with an inline petrol filter as a pulse damper and it's working fine. With the throttle closed the take-off is definitely on the engine side of the butterfly
Geoff
