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Posted: Wed Apr 13, 2011 1:58 pm
by bjmullan
Posted: Wed Apr 13, 2011 2:03 pm
by Mike
210bhp wrote:What is the number on the space cam in your newly rebuilt pump? i.e. Do you start with a 44 stamped cam to get to RSR spec or is your new cam a different starting point?
Sounds like a question for Herr Sattelberger, I'll give him a try.....should be out the toilet by now I would have thought!
Posted: Thu Apr 14, 2011 9:15 am
by Mike
210bhp wrote:What is the number on the space cam in your newly rebuilt pump? i.e. Do you start with a 44 stamped cam to get to RSR spec or is your new cam a different starting point?
Mike, Herr Sattelberger has confirmed the 44 space cam was from the 6.3 Mercedes. The correct part for my RSR engine with the factory configuration
of 50mm high butterflies, RSR sprint cams and the large 43mm ported heads is a V-109, hope that helps.
Posted: Thu Apr 14, 2011 10:08 am
by 210bhp
That's interesting Mike because that number does not seem to be similar to others especially the RS space cam. It is possible (I have read) to reprofile any space cam to a desired output within reason. However, it appears there must have had a different starting point (unique?) when the Bosch engineers were asked to create the RSR pump (space cam). I wonder if the space cam your friend has put into your pump is 'new' i.e. still available or a reprofiled unit.
It would be interesting to see another cam just to confirm that number. I know Edmond Harris has an 'original' for sale. You can check the number without taking the space cam off with a small dentist's mirror.
Thanks for the info Mike. Do you have a link to the company who rebuilt your pump?
Regards
Mike
Posted: Thu Apr 14, 2011 10:14 am
by Mike
Posted: Thu Apr 14, 2011 10:42 am
by bjmullan
210bhp wrote:You can check the number without taking the space cam off with a small dentist's mirror.
Told you all he was a bloody dentist!

Posted: Thu Apr 14, 2011 10:53 am
by Mike
210bhp wrote:I wonder if the space cam your friend has put into your pump is 'new' i.e. still available or a reprofiled unit.
Great image of Mike with an injection pump in the dentist's chair under the light, with his assistant, white coat and mask on, poking about with his mirror!
I could be entirely wrong here but from my very limited engineering knowledge I would guess that Bosch as the original manufacturer would have started
out with a blank cam forging which would be machined and then ground with the fueling profile necessary for the application it's required for, and then
stamped accordingly.
Koller, as the Bosch agents who have taken over all the factory servicing work and have all the original equipment from Bosch for it, are most insistent on
having a detailed build sheet of the engine they are doing the pump for so they can match the requirement exactly. Again I'm guessing but I would imagine
the more common the car/engine the more likely they would have something off the shelf, but for an unusual or rare application they must do the profile
specifically for it.
An example would be two identical RSR engines but one on high butterflies and one on slides, each would require different space cams in their respective
pumps to give the correct fueling requirement.
Posted: Thu Apr 14, 2011 11:01 am
by impmad2000
Just a quick aside guys, what determines the position of the pickup on the space cam , RPM and throttle position ? or is there a manifold pressure input aswell ?
Tim
Posted: Thu Apr 14, 2011 11:07 am
by hot66
an MFI pump is activated by RPM & throttle position ( in other words there is only a rod from the throttle linkage going to the pump + the pump is driven by belt off the nearside cam. Apart from those 2 'inputs' the MFI pump is a stand alone unit ( excluding the oil feed & return on road cars )
Additional things on a road car are : cold start enrichment & the atmospheric pressure enrichment / lean to adjust the fueling for altitude
Posted: Thu Apr 14, 2011 11:59 am
by Mike
210bhp wrote:I wonder if the space cam your friend has put into your pump is 'new' i.e. still available or a reprofiled unit.
Mike, they have just come back to me and confirmed what we suspected, the V-109 space cam is for a range of RSR's up to 3.6,
it's then individually modified for each specific application.
Hope that helps, are you concerned about your own cam?
Posted: Thu Apr 14, 2011 12:59 pm
by Gary71
It's not exactly a 3D map Tim

I'd imagine it aims at 'rich' or 'richer' depending on throttle position.
Posted: Thu Apr 14, 2011 1:13 pm
by impmad2000
Just thinking that since my EFI map, created TPS vs RPM, is essentially the same, it could be used as a tool to make custom MFI space cams.
The shape of the map is essentially the characteristics of the engine what ever is fuelling it.
If you were to profile an engine using EFI, TPS vs RPM exactly the same as MFI, feed the resulting map data into a CNC grinder, you could cut you own space cam for MFI based on the EFI engine plot.
Assuming little is changed between the EFI and the MFI (injector position, fuel spray, butterfly location, inlet trumpets etc) I see no reason why the map won't be accurate !!
Just wild thoughts really, possibly rubbish !
Tim
Posted: Thu Apr 14, 2011 1:47 pm
by 210bhp
Mike wrote:210bhp wrote:I wonder if the space cam your friend has put into your pump is 'new' i.e. still available or a reprofiled unit.
Mike, they have just come back to me and confirmed what we suspected, the V-109 space cam is for a range of RSR's up to 3.6,
it's then individually modified for each specific application.
Hope that helps, are you concerned about your own cam?
No concern over mine.
I am trying to put together a list of space cam engraving numbers that should match the pump tag number. Not that I am ever likely to be buying an RSR pump, but it would be nice to know what space cam to expect inside. More of an issue on T E S and RS pumps as there seem to be a few for sale recently (in the States).
Tim's observations are interesting.
Just trying to understand more about MFI all round as there seems to be a distinct lack of knowledge in the UK (hence you went to Germany).
Regards
Mike
Posted: Fri May 13, 2011 6:30 pm
by Mike
Don't get excited, just a bit of harness detail!
Had been looking for the correct buckles for the harnesses for a couple of years, had a handed pair but I needed two the same.
Early 'S' Registry came to the rescue again, thanks Bill.
As for the car, waiting for a slot in the spray booth at Sportwagen, multi million pound Bugatti's and stuff keep getting in the way!
The rebuilt dizzy is on it's way back from the States, the last piece in the engine puzzle so expect news of a dyno run soon, honest

Mike's RSR
Posted: Tue May 17, 2011 8:00 pm
by The Minotaur
Aye, that'll be right!!!!!! Same geological time scale as my engine rebuild.
Tim