7,5 mm Element design for high performance engine
7,5 mm Element design for high performance engine
As some of you here on the STD forum knows, I have been struggling with making my own pumpelement for the M-seriepump. I want to reveal some facts what I have done the last year.
Previously I have done pumps with the "old" 7 mm Ford Transit element, Also with the 6 mm original OM606 element. My opinion was that the 7 mm didnt work out well at all, High knock at low idle, high fuelconsumption max 120cc was some of the disadvantages with those.
6 mm was running perfect, good balance nice idle and so on.
After those pumps my customers wanted moore fuel, Myna was running 170cc with there own 7 mm element, However I could not buy those, Myna dont sell element only, they just put them in there own pumps. The explanation I got was that
-It is some difference in quality.
At this moment I have around 10-15 pumps waiting for nice, big element whit a lot of fuel.
Something had to bee done
I started do design the first serie of 7,5 mm element, It took around 3 months for the factory to make them for me.
At this moment I have payed around 8000 euro.
After 4 months the goods arriwed, I was glad for about 4,5 minute, then everything went to ****.
Barrel was too big, didnt even fit in the pumphousing, plunger was 0,15mm to long, The plunger could not go to top in the pump, it was stuck.
This however I could fix, my friend, who has a mechanical workshop helped me.
Barrels was grinded down to right dimensions so that they fitted in the housing, plunger was modified so that I could mount them in the pump.
First pump was 2,5 degrees wrong in phasing, That was no big deal, but it gave me a lot of extra work, changing rollers in the tappet lifter so the balance was OK.
Next thing was fuelquantity, I was expecting a bit over 170cc but no.
140-150 cc was max at 21mm of rack BUT, It had capacity for OVER 200cc
The "only" thing was that the helixangel on the element was to flat, I would need around 25-26 mm of rack to get 100% out of the element.
80 elements where adjusted, 10pc of 140cc pumps was built with good result. I bougt a 250TD with OM605 just for testing the pumpelements properly.
Rest of the elements where shipped back to the factory for modification.
Serie 2 was up on drawingtable, wise from the first serie I know now how it should bee designed, Serie 2 has som benefits that serie 1 dont have.
Here is a small teaser
50 days from today and serie 2 will arriwe for testing. After that gentlemen, I think that I can offer you some nice pumps.
140cc & a bit moore.