Injector information
 

Hi guys,

Our M120 engine currently has the OEM injectors Part number 0000785049 which I believe are 200cc/min or close to that.

We are looking to grow the performance of our engine and ideally need to run larger injectors. We know we can use aftermarket injectors and make them fit etc, but I just wondered if anyone knew of any MB or OEM injectors that will fit in place of the stock units but are 300 or 400cc/min instead ? They are 14mm size top and bottom o-ring.

We are running an aftermarket ECU so tuning is not an issue.

Any specialists out there who might know ??

The injectors you have are a pretty standard size and it would probably be harder to find injectors that wont fit than ones that do. The aftermarket is rife with options, the most important question is whether you want to run low or high impedence injectors. Next most important is how much hp you intend to make. With that info you should be able make an informed selection.

To be honest it doesn't matter to us if we run low or high impedance injectors as our ECU will drive both.

Power wise I'm hoping we can get between 500-550HP.

Plugging your numbers into an injector calculator comes up with 275cc injectors to reach your target assuming you run a m/b 4 bar regulator and leave 20% headroom. I'd be tempted to go with something a bit larger maybe 300 to 325 cc in case later tuning surpasses your current target. Not that it matters much in your build but I'm sure that wouldnt be too large for good low rpm manners.

Yeah sounds about right. Was just hoping someone would be able to say......... XXXXXXXX model number is 400cc and will fit.

I dont have part numbers for you but I'd expect any EV1 injector beteeen 25-35 lb/hr would work for you. Dont forget most injectors are rated at 3 bar and the stock regulator in the m/b rail is 4 bar.

Sweet as, thanks for the information, it's very much appreciated.

I'll do some more digging, but that info helps. Wasn't aware the stock MB pressure reg was 4bar

The spec is 3.6 to 4.2 bar. Less at high manifold vacuum more a low vacuum. My injectors are rated 36lb/hr but flow right at 40lb/hr at 4 bar.