MAP sensor
Dave Plowman (News)
I've built a programmable ignition set for the old SD1 from a Jaycar kit.
The distributor is getting tired and I thought I'd give it a go as I
reckon it was never a particularly well matched advance curve for unleaded
even when perfect.
Anyway, I need a MAP sensor to feed the manifold vacuum info to the
processor. Bulkhead mounting would be nice - as would one which uses an
easily sourced plug. It needs to be analogue output working off 5 volts -
which I believe is pretty standard apart from Ford - and a 1 bar type is
fine.
--
*I don't work here. I'm a consultant
Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.
David Billington
> It *is* about a classic - honest. ;-)
>
> I've built a programmable ignition set for the old SD1 from a Jaycar kit.
> The distributor is getting tired and I thought I'd give it a go as I
> reckon it was never a particularly well matched advance curve for unleaded
> even when perfect.
>
> Anyway, I need a MAP sensor to feed the manifold vacuum info to the
> processor. Bulkhead mounting would be nice - as would one which uses an
> easily sourced plug. It needs to be analogue output working off 5 volts -
> which I believe is pretty standard apart from Ford - and a 1 bar type is
> fine.
>
>
to 2 bar, for NA you could use the 0 281 230 004, this was a automotive
MAP sensor sold for aftermarket use. I don't know if the specific part
is still available or superceded as the Bosch site make finding the info
hard, maybe they removed it. It fits your requirement though of 5V
supply and analogue output. You might also look at the ones used by
Megasquirt, IIRC they would also do and last time I looked a year or so
ago were stocked by RS.
David Billington
http://www.bosch.com.au/content/language1/downloads/Map_Sensor_Technical_Specification.pdf
Dave Plowman (News)
David Billington <d...@djbillington.freeserve.co.uk> wrote:
> You might also look at the ones used by
> Megasquirt, IIRC they would also do and last time I looked a year or so
> ago were stocked by RS.
Thanks for the heads up - despite using electronics suppliers I never
thought to try them.
Got exactly what I wanted from Farnell - at about 15 quid rather than the
75 or so for 'car' ones. Only difference is it has Molex connectors rather
than an automotive one.
--
*There are 3 kinds of people: those who can count & those who can't.
Chris Morriss
<da...@davenoise.co.uk> writes
> It *is* about a classic - honest. ;-)
>
> I've built a programmable ignition set for the old SD1 from a Jaycar kit.
>The distributor is getting tired and I thought I'd give it a go as I
>reckon it was never a particularly well matched advance curve for unleaded
>even when perfect.
>
> Anyway, I need a MAP sensor to feed the manifold vacuum info to the
>processor. Bulkhead mounting would be nice - as would one which uses an
>easily sourced plug. It needs to be analogue output working off 5 volts -
>which I believe is pretty standard apart from Ford - and a 1 bar type is
>fine.
>
I've used one off a Rover 827 (Honda V6 engine). This is found in a big
black plastic box with other sensors and solenoids in it, and is
connected to the inlet manifold by a length of vacuum pipe. It's easy
to remove and is physically robust. As you say, it uses a stabilised
+5V supply and has a linear transfer function up to approx 1.7 Bar.
Perhaps other EFI Rovers or Hondas from the late 80s use the same one.
--
Chris Morriss
Dave Plowman (News)
Chris Morriss <cr...@oroboros.demon.co.uk> wrote:
> I've used one off a Rover 827 (Honda V6 engine). This is found in a big
> black plastic box with other sensors and solenoids in it, and is
> connected to the inlet manifold by a length of vacuum pipe. It's easy
> to remove and is physically robust. As you say, it uses a stabilised
> +5V supply and has a linear transfer function up to approx 1.7 Bar.
> Perhaps other EFI Rovers or Hondas from the late 80s use the same one.
Thanks Chris, but hopefully sorted when it arrives from Farnell.
Just another question since you seem to be on the programmable ignition
wavelength - the kit has the option of a knock sensor. Worth the bother -
and any idea where it (they) fits on a Rover V-8?. And same question about
which to use?
--
He who laughs last, thinks slowest*
Badger
"Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
news:4fe0d10...@davenoise.co.uk...
> Just another question since you seem to be on the programmable ignition
> wavelength - the kit has the option of a knock sensor. Worth the bother -
> and any idea where it (they) fits on a Rover V-8?. And same question about
> which to use?
Dave, std ones as used on the later DiscoII (Thor engine) and P38 rangerover
(both Gems and Thor variants) are fitted either side of the block on an
extra boss that is cast in next to and slightly above the middle core plug
on each side of the block. I think they work on a stabilised 5v supply.....
Badger.
Dave Plowman (News)
Badger <brian...@btinternet.com> wrote:
That was my fear that they were sort of built in. I'm thinking of
fabricating brackets that attach to the exhaust manifold fixings.
--
*Virtual reality is its own reward *
David Billington
> In article <gZCdnSb9v_kfBU_V...@bt.com>,
> Badger <brian...@btinternet.com> wrote:
>
>
>> "Dave Plowman (News)" <da...@davenoise.co.uk> wrote in message
>> news:4fe0d10...@davenoise.co.uk...
>>
>>> Just another question since you seem to be on the programmable
>>> ignition wavelength - the kit has the option of a knock sensor. Worth
>>> the bother - and any idea where it (they) fits on a Rover V-8?. And
>>> same question about which to use?
>>>
>
>
>> Dave, std ones as used on the later DiscoII (Thor engine) and P38
>> rangerover (both Gems and Thor variants) are fitted either side of the
>> block on an extra boss that is cast in next to and slightly above the
>> middle core plug on each side of the block. I think they work on a
>> stabilised 5v supply..... Badger.
>>
>
> That was my fear that they were sort of built in. I'm thinking of
> fabricating brackets that attach to the exhaust manifold fixings.
>
>
I think the main thing is you have a good solid fixing to the block
without flexure as they're basically an acoustic pickup, you wouldn't
want possible relative movement giving false indications (noise).
Dave Plowman (News)
David Billington <d...@djbillington.freeserve.co.uk> wrote:
> > That was my fear that they were sort of built in. I'm thinking of
> > fabricating brackets that attach to the exhaust manifold fixings.
> >
> >
> Dave,
> I think the main thing is you have a good solid fixing to the block
> without flexure as they're basically an acoustic pickup, you wouldn't
> want possible relative movement giving false indications (noise).
Indeed - I assume they're just some form of contact mic. I was thinking of
supporting it by a bracket, but actually using epoxy to stick it to the
block. But open to better suggestions. ;-)
--
*Remember not to forget that which you do not need to know.*
Mike G
> In article <48d2ceed$0$26084$db0f...@news.zen.co.uk>,
> David Billington <d...@djbillington.freeserve.co.uk> wrote:
>> > That was my fear that they were sort of built in. I'm
>> > thinking of
>> > fabricating brackets that attach to the exhaust manifold
>> > fixings.
>> >
>> >
>> Dave,
>
>> I think the main thing is you have a good solid fixing to the
>> block
>> without flexure as they're basically an acoustic pickup, you
>> wouldn't
>> want possible relative movement giving false indications
>> (noise).
>
> Indeed - I assume they're just some form of contact mic. I was
> thinking of
> supporting it by a bracket, but actually using epoxy to stick
> it to the
> block. But open to better suggestions. ;-)
For a solid fixing, I would suggest drilling and tapping the
block. No doubt they would break into the water jacket, but a
pair of brass inserts screwed in with sealant, maybe using
'Loctite Retainer' so they wouldn't easily unscrew if the sensor
bolt became tight, would not cause any problems as far as water
leaks were concerned, and I can't think of a better way to get a
really solid fixing.
With a central blind hole tapped to suit the knock sensor, you'd
have a fixing as solid as any OE fitted one. I certainly wouldn't
advise you glue them. I don't think they would stay glued for
long.
I could make the inserts for you if you decided on that method.
All I would need to know is the water jacket thickness, (easily
checked after drilling) and the sensor bolt diameter.
If you're interested, I assume you still have my email address.
Mike.
*If you're doing nothing, how do you know when you've finished?*
David Billington
> In article <48d2494e$0$2510$da0f...@news.zen.co.uk>,
> David Billington <d...@djbillington.freeserve.co.uk> wrote:
>
>> You might also look at the ones used by
>> Megasquirt, IIRC they would also do and last time I looked a year or so
>> ago were stocked by RS.
>>
>
> Thanks for the heads up - despite using electronics suppliers I never
> thought to try them.
> Got exactly what I wanted from Farnell - at about 15 quid rather than the
> 75 or so for 'car' ones. Only difference is it has Molex connectors rather
> than an automotive one.
>
>
catalogues dried up, and they pushed more to the website I stopped
buying from them and switched to RS. I didn't have a RS catalogue but I
found RSs website vastly superior to Farnells and it still is by the
look of it. I found using Farnells website a waste of time when it might
take an hour to get an order together that would take 10 minutes with
the printed catalogue.
Dave Plowman (News)
Mike G <met...@largefoot.com> wrote:
> > Indeed - I assume they're just some form of contact mic. I was
> > thinking of
> > supporting it by a bracket, but actually using epoxy to stick
> > it to the
> > block. But open to better suggestions. ;-)
> For a solid fixing, I would suggest drilling and tapping the
> block. No doubt they would break into the water jacket, but a
> pair of brass inserts screwed in with sealant, maybe using
> 'Loctite Retainer' so they wouldn't easily unscrew if the sensor
> bolt became tight, would not cause any problems as far as water
> leaks were concerned, and I can't think of a better way to get a
> really solid fixing.
Hmm. It would certainly make for a good fixing, but I'm not sure the
sensors - being a type of microphone - are a) waterproof, b) would cope
with the pressure of the coolant and c) wouldn't get confused by the sound
of the coolant rushing past the diaphragm. The circuit does include a high
pass filter to remove unwanted noises from those to be sensed but My
feeling is it wouldn't filter that out.
Of course it's only guessing on my part.
> With a central blind hole tapped to suit the knock sensor, you'd
> have a fixing as solid as any OE fitted one. I certainly wouldn't
> advise you glue them. I don't think they would stay glued for
> long.
My thoughts were to support if firmly with a bracket bolted to the
exhaust manifold fixings as well as gluing to the block. Although some
subsequent research on Google shows contact may not be necessary.
> I could make the inserts for you if you decided on that method.
> All I would need to know is the water jacket thickness, (easily
> checked after drilling) and the sensor bolt diameter.
That's very kind, Mike.
> If you're interested, I assume you still have my email address.
I do indeed.
--
*Learn from your parents' mistakes - use birth control
Mike G
You missed the part about the sensor fixing being blind.
Imagine a solid plug screwed into the block. Say 12mm long. The
plug is then drilled 10mm deep and tapped to suit the sensor, so
the sensor never contacts the water.
Im thinking of the sensors that are mounted on a flat surface,
and retained by a bolt that passes through them. The ones like a
thick washer, for want of a better description.
Mike.
Dave Plowman (News)
David Billington <d...@djbillington.freeserve.co.uk> wrote:
> > Thanks for the heads up - despite using electronics suppliers I never
> > thought to try them. Got exactly what I wanted from Farnell - at about
> > 15 quid rather than the 75 or so for 'car' ones. Only difference is it
> > has Molex connectors rather than an automotive one.
> >
> >
> That's good. I used to have an account with Farnell but as their printed
> catalogues dried up, and they pushed more to the website I stopped
> buying from them and switched to RS. I didn't have a RS catalogue but I
> found RSs website vastly superior to Farnells and it still is by the
> look of it.
I'm not sure there's much between them once you suss them out. They are
both slow if you have a slow connection or computer.
> I found using Farnells website a waste of time when it might
> take an hour to get an order together that would take 10 minutes with
> the printed catalogue.
I tend to use Farnell/CPC cost wise. And Rapid. RS tend to be a last
resort. ;-)
--
*Someday, we'll look back on this, laugh nervously and change the subject
Mike G
"Mike G" <met...@largefoot.com> wrote in message
news:6jhk3cF...@mid.individual.net...
I should have added that the same principle could be used for the
type that screw into the block, but for that type I'd need to
know the thread spec of the sensor, which could be an odd thread.
Mike.
David Billington
> In article <48d38049$0$2934$fa0f...@news.zen.co.uk>,
> David Billington <d...@djbillington.freeserve.co.uk> wrote:
>
>>> Thanks for the heads up - despite using electronics suppliers I never
>>> thought to try them. Got exactly what I wanted from Farnell - at about
>>> 15 quid rather than the 75 or so for 'car' ones. Only difference is it
>>> has Molex connectors rather than an automotive one.
>>>
>>>
>>>
>> That's good. I used to have an account with Farnell but as their printed
>> catalogues dried up, and they pushed more to the website I stopped
>> buying from them and switched to RS. I didn't have a RS catalogue but I
>> found RSs website vastly superior to Farnells and it still is by the
>> look of it.
>>
>
> I'm not sure there's much between them once you suss them out. They are
> both slow if you have a slow connection or computer.
>
>
component so I could make a decision quickly, I found the Farnell site
presentation poor and the data had to be downloaded if present. RS at
least had quite a bit of data on the webpages detailing many of the
components so was far quicker to get an order together.
>> I found using Farnells website a waste of time when it might
>> take an hour to get an order together that would take 10 minutes with
>> the printed catalogue.
>>
>
> I tend to use Farnell/CPC cost wise. And Rapid. RS tend to be a last
> resort. ;-)
>
Must look at CPC as I haven't in awhile. Got a nice shiny new Maplins in
Bath now so for odds and ends I can pop in there and pick them up.
David Billington
> In article <6jgegdF...@mid.individual.net>,
> Mike G <met...@largefoot.com> wrote:
>
>>> Indeed - I assume they're just some form of contact mic. I was
>>> thinking of
>>> supporting it by a bracket, but actually using epoxy to stick
>>> it to the
>>> block. But open to better suggestions. ;-)
>>>
>
>
>> For a solid fixing, I would suggest drilling and tapping the
>> block. No doubt they would break into the water jacket, but a
>> pair of brass inserts screwed in with sealant, maybe using
>> 'Loctite Retainer' so they wouldn't easily unscrew if the sensor
>> bolt became tight, would not cause any problems as far as water
>> leaks were concerned, and I can't think of a better way to get a
>> really solid fixing.
>>
>
> Hmm. It would certainly make for a good fixing, but I'm not sure the
> sensors - being a type of microphone - are a) waterproof, b) would cope
> with the pressure of the coolant and c) wouldn't get confused by the sound
> of the coolant rushing past the diaphragm. The circuit does include a high
> pass filter to remove unwanted noises from those to be sensed but My
> feeling is it wouldn't filter that out.
> Of course it's only guessing on my part.
>
http://www.bosch.com.au/content/language1/downloads/sensors_knock.pdf
and shouldn't have any problem with bits getting wet from the look of it
if you tapped right through into the water jacket.
Mike G
"David Billington" <d...@djbillington.freeserve.co.uk> wrote in
message news:48d3a139$0$26080$db0f...@news.zen.co.uk...
That's the type I'm thinking about, but ideally they should be
bolted to a flat surface. Unlikely with a cast block. Another
disadvantage is that replacing them for whatever reason would
allow water to leak from the cooling system.
The brass adaptors idea overcomes both those problems.
Apart from that it's a much more elegant solution. :-)
Mike.
Mike.
Chris Bolus
CPC *is* Farnells...
Maplins is useful and convenient, but not as cheap, and just doesn't
have the range of Rapid & CPC. Like Dave, RS is a last resort!
--
Regards, Chris (Please take out my car to reply by plain text email)
------1967 Riley Elf------1978 Mini 1000------1971 Mini Clubman------
--1972 Mini Clubman estate--1979 Ford Capri--1984 VW Type 25 camper--
David Billington
content was significantly different to Farnell. I see CPC advertise on
TV now, not seen Farnell yet. I get the impression they are focused on
different market sectors. I know RS are not the cheapest but I use them
when they have the parts and I don't know a cheaper supplier or the part
is far easier to find on their site and my time is costing me. Will have
a look around CPC and Rapid site and see if they are useful.