Injector geometry

[Frederic Breitwieser]

> I am ready to poke some holes for injectors in my mopar 440 tunnel ram.
> My question is it appears that I will not be able position the injectors
> to point directly at the back of the intake valve. How important is
> this? The injectors are 36# Ford Motor sports units.

Ya, tunnel rams have very long, downward tubes.  You should try to
inject at the valve backs the best you can, but its not mission
critical.  You might consider milling the injector boss holes on an
angle, to inject it into the airstream.  I chose to keep it real simple
and bore perpendicular to the valley plane, and after testing the design
on the engine, its okay and I'm not really worried about it.

> However this will make for some difficult machining in a tight spot.

Machine from the intake ports upwards through the runners on an angle...
then weld the bosses in, then grind enough of the inside of the boss
away that the injector still seals good, yet is slightly exposed
tip-wise.

Honestly, Unless you are building a very high performance engine, its
not the most critical thing in the world from what I can tell with my
383 stroker (431 cid).

I used a streetmaster aluminum intake.

http://www.xephic.dynip.com/dodge/dodge.html

Off the left-handed menus, select "Engine" then "383swap" then "EFI
Intake", and you can see what I ended up with.