yes this works
you can also increase the diameter of the rail too
just be careful not to upset the area wher the ends are sealed (o-rings), unless you are converting to AN style fittings

later
tim3kgt

 

yes this works
you can also increase the diameter of the rail too
just be careful not to upset the area wher the ends are sealed (o-rings), unless you are converting to AN style fittings

later
tim3kgt

Do you have any info. on how this is done

 

I thought about doing this "ported fuel rails" a while back but i realized that it would not really do anything.

I sliced a rail right at an injector hole and placed an injector in the now half hole and the "half moon" part of the rail is a pretty good distance away from the injector inlet.

Based on fluid flow characteristics i decided that this was not worth the time it takes to port all 6. (you can't just drill, or you stand a good chance of damaging the sealing surface.)

The main passage through the rails is also plenty large, probably enough to support 800-1000hp.

:mitsu:

 

I took mine to a machine shop and had them drilled out to 1/2" straight through. The bit that he had was only about eight inches long, so he had to drill one side, flip it around, then drill the other side. Then I took a Dremel and ported out the injector feeds. Cost: $40

 

The stock rails will support more power than 99.9% of any setup that will ever exist.

 

The stock rails will support more power than 99.9% of any setup that will ever exist.

Read this! Very informative and easy to do.

http://www.proplusfx.com/fuel/index.htm

 

Brett Farnam used to do this along with a small fuel system upgrade. He no longer does these anymore though.
Heres some pictures in this thread http://www.3si.org/forum/showthread.php?t=154367&highlight=Farnam

 

I had mine machined and to fit AN fittings on the ends, and ported the 'injector' holes a little more with a dremel. It is almost not worth it, though. Im gonna say dont buy the overpriced GTPoop rails, but make your own or talk to a company that makes them for mitsu cars and get some cut to 3 holes at out spacing. Im trying to find some DSM rails to see if the spacing is the same between injectors (not likely), but if not, ill either try to get some company to machine some new ones with better flow characteristics, make my own (google search should help you find info on this), or do the extanded rail setup.

Exteneded rail:

Run a rail with male nipples, barbs, etc etc. Injectors in head, tube between rail and injector head. clamp it and call it a day. If you wanna see pictures of this, look for what people do on extra-injetor setups. This is common in that arena.


Good luck, and if you want some ported stock rails, lemme know


Sean

 

whats wrong with our fuel rails right now? will drilling out actually make a noticeable difference?

 

whats wrong with our fuel rails right now? will drilling out actually make a noticeable difference?

Nothing at all, like I stated, there is maybe .01% of 3S owners that would ever think about outflowing the stock rails. You would need 1000CC+ injectors to get close to tapping them out, even then I don't think you are going to be close. Some things are just gimmik. You don't need them.

 

whats wrong with our fuel rails right now? will drilling out actually make a noticeable difference?

Not really a DIFFERENCE, more like oreventative maintenence. You are always striving for better flow.


Sean

 

Nothing at all, like I stated, there is maybe .01% of 3S owners that would ever think about outflowing the stock rails. You would need 1000CC+ injectors to get close to tapping them out, even then I don't think you are going to be close. Some things are just gimmik. You don't need them.

thats wut i was thinking. thanks for the quick response

 

How do you know your not disrupting flow by removing the shrouding?

Sam

 

I think the main issue Brett had with the rails when he was machining them out was that although the rails seem to be more than adequate at a glance, apparently towards the center of the rails many of the diameters get as narrow as 1/4" or less. This was thought to be caused by the machining process from the factory to make it easier for them to remove their dyes or something like that I think. (I forget exactly what the reasoning was).
Personally, I'm just going to have mine bored to 1/2" for now with AN fittings tapped on with IPO's dual pump bolt on kit. That will be more flow than anybody would ever need on a 3S I'm guessing.

 

I bought a set of Bret Farnam's rails from a member who had them on his 99 VR4. I compared them to my stock rails and you can really see a difference- a BIG difference. This can be done rather cheaply at any local machine shop so it can't hurt. I want to make sure I have enough flow going to my injectors. I'd rather spend ~$100 now then ~$2500 when my engine leans out and melts a piston.

 

How do you know your not disrupting flow by removing the shrouding?

Sam

good question, maybe they are designed that way on purpose!

 

I bought a set of Bret Farnam's rails from a member who had them on his 99 VR4. I compared them to my stock rails and you can really see a difference- a BIG difference. This can be done rather cheaply at any local machine shop so it can't hurt. I want to make sure I have enough flow going to my injectors. I'd rather spend ~$100 now then ~$2500 when my engine leans out and melts a piston.

Of course there is a difference, question is, is the difference needed? for 99.9% of 3S owners it is not. Unless you are looking for 1000+HP I don't see the stock rails as an issue. You are not going to lean out with 600-800HP because the stock rails. It just aint going to happen.

 

These fuel rails have the taper in them making it easier to get the cast out during manufactoring. They are then CNC machined for the injectors using an endmill which has a flat bottom, can't use a drill as it would catch once it brakes thru and result in an uneven hole. This is the easiest way to manufactor them, it would cost more to take out the shrouding or any other any other imperfections. Buy opening up these your allowing fuel to evenly flow thru it without any restrictions. Very simple mod to do yourself, I bought an extra set for $20 so I can do this myself when I start modding and adding new fuel injectors. Might even just make my own fuel rails, just as easy to do.

 

Doesn't seem like there is a restriction here, also notice the main hole is offset, not allowing much space for material removal...........

 

The "oval" opening for the injector feed is plenty large..........

 

Here's what I did.

 

wow that is alot of replies sence i read last

i searched on the forum but i either got no matches found
or i got a lot of stuff related to the EK2 kit

so i figured i would post

i didnt really realize how good our fuel rails were from what i have read on gtpro is that the stock ones are not good at all and they are restrictive but i guess i should have made more effort into it

i am going to try it
i figure why not
it is a small increase but never the less it is still an increase,
and i am looking for evry little bit i can get


i have a extra set i will attempt it on

a freind of mine has a metal shop where he might be able to machine them out for me if i am not able to do it myself


thanks for all the imput
wayne S