Fuel injectors facing upwards

[gibbon]

Hi all, I'm building the most amazing inlet manifold ever, and because I have zero fabrication skills, its all preexisting parts and adapter plates 

The problem I've run into is that an existing mount stud fouls directly on an injector boss. If I flip everything 180 degrees, it clears ok. The downside is that the injectors will be effectively upside down. Is this going to cause a problem?

It's a cross flow engine at least, so leaking seals wont mean fuel on the exhaust manifold 

[Yowzer]

Nothing wrong with injectors firing upwards. There's a number of aftermarket manifolds with the injectors on the underside for either fitment or a cleaner look.

[gibbon]

Thanks mate that's what I wanted to hear. I was just aware that every manufacturer had them the usual way around, guess it's a maintenance/access thing for them 

[Kiwibirdman]

They usually point down so the fuel is sprayed onto the back of the inlet valve. This is the optimum position, spraying upwards is less than optimum but still better than a carby or throttle body injection.

[Ranter]

On ‎17‎/‎07‎/‎2020 at 17:50, gibbon said:

Hi all, I'm building the most amazing inlet manifold ever, and because I have zero fabrication skills, its all preexisting parts and adapter plates 

The problem I've run into is that an existing mount stud fouls directly on an injector boss. If I flip everything 180 degrees, it clears ok. The downside is that the injectors will be effectively upside down. Is this going to cause a problem?

It's a cross flow engine at least, so leaking seals wont mean fuel on the exhaust manifold 

Yeah the leaking fuel doesn't need a manifold to ignite it, one of my Starions lit up in about 5 seconds from leaking injector seals which surprised me somewhat as a long time Mitsi owner and not new to the fuel leaks after sitting for some time.

I haven't had a 12v in over twenty years but I thought there was a Mirage inlet manifold that matched the 12v Dash engines? (I had to four extra inlet valves on a switch for no reason other than who else can switch off valves lol)

[gibbon]

4 hours ago, Ranter said:

Yeah the leaking fuel doesn't need a manifold to ignite it, one of my Starions lit up in about 5 seconds from leaking injector seals which surprised me somewhat as a long time Mitsi owner and not new to the fuel leaks after sitting for some time.

I haven't had a 12v in over twenty years but I thought there was a Mirage inlet manifold that matched the 12v Dash engines? (I had to four extra inlet valves on a switch for no reason other than who else can switch off valves lol)

I've just spent the last hour looking at various mirage engines but cant see anything that looks like itd bolt up... it doesn't help that the mirage had something like twenty different engine fit outs. If you can think of any other distinguishing features of the engine that this manifold is from, I'd love to hear about it, thanks