Contour Enthusiasts Group Archives Forums Modifications 3.0L Duratec Injector Spray in Port Matched Oval Port Heads?

I think that TH and I are on the same page here. I cut mine to aim directly at the back of the valve ... just like the stock setup because I'm retaining the use of the stock injectors. I guess the better question here is who is aiming at the center and using the stock injectors? If you are, you may not be helping at all and may be hurting your fueling atomization. Now, if you have and you are using the oval port injectors, you are accomplishing what you thought you would when you cut the heads. The key variable here and what Terry is pointing out is that the injector spray pattern is different in the two heads and most people that use the oval port heads and retain the split port injector location reuse their split port injectors.

exactly what tom said....

you can't "aim" the injector...it's gonna spray the same unless you modify the LIM. I just slightly cut mine to right hoping that when my 2ndaries open up...that extra cut will help the air pull a little more fuel to the right.

But I don't think anyone has aimed any injectors anywhere

Thanks for clarifying that Tom ... that is exactly what I was thinking but forgot to mention. When I said "aim", I meant the angeling of the channel, not the injector. It's a given seeing as how the injector is aimed based on it's fixture in the LIM. It would take more than just recutting the LIM, you would have to actually modify the fuel rail as well since the top "cap" has very little deflection or "wiggle" room to "point" the injector face.

So basically what you're saying is that I should be fine, especially if I just grinded the injector lanes on the heads out a tad more?

You do have room for it.

In it's currant form, it may just disperse the spray pattern a bit more by hitting such a ramp which may help atomisation, and since the A/F mixture is more or less drawn in once the valves open it might not be a bad thing.

Just a theory anyway. It isn't what I did, but it sounds like it could be an option to me.

I would think that the opposite would be true. Liquid particles that are forced to share the same place normally congile into larger particles ... they "pool" together. Like TH said, it would depend mostly on the velocity of the air in which the particles are being injected. This was my theory and why I made my injector valley as deep and spread out as I could. Mine started out deep and shallow and then bleeds out and expands as it meets the floor of the chamber behind the valve.

.....oval port with offset injector is a compromised
system.It's neither a good spray angle for a twin port
as you are now spraying into an oval in an offset
position and not good for an oval as you still have a
secondary,closed,above the second valve with a 'snake'
airflow and lowered velocity.Only a custom injector
with a clocked nozzle head and modded spray angles,2
for the the 'open' lim and 2 to try to traverse the
added distance from the injector across the port to
the second valve may help the poor spray pattern to
the second valve or a two injector system per
cylinder.....the airfow thru one port of the lim is
off when secondaries are closed and the injector spray
position is off when the secodary is open....neither
is good for fuel mixing .The stoc twin port system
injects air fuel to one port all the time,when the
secondary opens all that does is add more air to water
down the over rich mix in the injector port....that
'final' mix happens in the cylinder .The best place to
get this mix right would be in the port,as a stoc
central injector 3.0 does with an oval port.....might
as well weld in a wall to an oval port and call it quits......

OK, this thread has bugged me for a bit now and I have to put in my final word. Take it for what it's worth.

There is much more to porting and mod'ing these heads to do well. Relocating the port injector is simply ONE step in a multi-step process. Relocating the injector port is one of the EASIEST mods to these heads one has to make to put some serious power down with them. There's a ton of other things you have to do to get these to work well! The total amount of time I put into my heads, the injector ports had a tiny fraction of it. Attention is needed elsewhere to pull these multiple modifications off. Look at my dyno proof with a craptastic break in tune for proof, if you need to.

When one is able to produce power in NA or FI form that is simply wicked for this platform to even handle, why would you go to the trouble to retain the center injection port!? If it's that optimal, than go ahead and make a custom LIM and fuel rail to retain it and keep the Aluminum UIM's, or show me an engine in a Contique that has retained the POS plastic UIM/LIM that has made some power worthy of mentioning past a daily driver amount.

As "compromised" as my system is, I'm doing really f$*%ing well

I ususally don't say this but this puppet posting by TH is getting a bit annoying. If he want's to post here than he should re-join our community.

Every setup is a bit of a compromise unless you have the big $$ to tool up your own castings to you exacting specifications etc. I know my setup isn't 100% perfect but it works well enough for a streetable NA setup. There are certian things I would change if I had the $$ to do so but the gains I would likely see in return would be far less than the total dollars spent to achieve that ultimate number. Also everyone who does this has their own idea of what the ideal setup for them is. For me it was retaining the stock look of the 2.5L engine but also gaining the additional oil drainbacks which should help the longevity of my engine (espically considering the hard track abuse my car will continue to enudure). One thing that I find interesting is that dollar for dollar these poor offset injector locations (as TH claims they are) on the modified oval port heads have for the most part made more HP or at minimum the same HP as ported split port "hybrid" 3L's for less money. Bottom line is everyone makes thier choice of what they want to do for thier build and it is up to them to make the most educated decision as to what the best options are for themselves.