Installing RX7 injectors in R33.

[JimX]

I've got a set of purple top RX7 injectors and I'm having some problems fitting them in. I've got a modified RB20 fuel rail which they fit into quite nicely, but not with the O-rings. I tried pushing them in with the O-rings lubricated with a bit of WD but they won't go in very easily at all. I don't want to push them in too hard in case something breaks.

The O-rings are looking a little tired anyway, I was thinking of buying a new set. Can someone tell me where I can get some from and what I am asking for exactly?

Also, the plastic wiring loom clip doesn't fit. It looks similar though, is it possible to modify the clip slightly to make it fit? If not, where can I get some clips that will fit?

Thanks in advance for any advice.

[GTS-t VSPEC]

I think Steve had a thread where he replaced the o-rings on his injectors, might be worth a seach.

[JimX]

Yeah I think I remember that thread, from memory his were too small I'll search back and see what he did.

[Steve]

Mine were side feed sards:)

Killer T has these injectors fitted, not sure if he fitted them himself? Might be worth a pm if he is still about.

New o-rings should only cost a couple of dollars each, and you should be able to source them from any fuel injection shop, or rotary shop. Would be a good idea to do this as matter of course, as if one goes on you life could get pretty messy, especially whilst boosting:p

I would hope they are pretty tight or they wont seal. I used engine oil to lube my sards up, and they were a pretty tight fit. Perhaps you need a slightly bigger holes in the fuel rail? Any engineering company should be able to help you out there, or a decent performance shop - hills would definately be able to help.

[JimX]

Well, the injectors themselves without the O-rings on fit almost perfectly. They just go straight in and are quite a snug fit without needing any force to push in. I think I just think the O rings need to be either newer/softer or just a tiny bit smaller. I'll take the lot in to an injection shop and see if they can help me with the plugs as well.

Anyone got any shop recommendations for a shop? Worst case I'll just take it to Hills when I'm ready to get it fitted, but for this simple stuff I'd rather do as much as I can at home. I'm pretty sure I can fit the whole thing myself as long as I get the O rings and wiring sorted. Should save an hour or 2 on labour at the workshop

[Steve]

If you fit them yourself, you will probably save a couple hundred in labour if you still have the stock plenum - good work.

[JimX]

I've got a front-facing plenum. This is the only reason why I bothered with the top-feed injectors really, I've heard it's a major pain in the arse to fit top-feeds under the stock plenum.

[Steve]

:uh-huh: especially when you forget to pressurise the fuel rail and check for leaks before bolting the mungrel back on...hehehe

[4door_Sleeper]

A few pictures would be good. I am looking at installing RX7 injectors on my R33, but am unsure on what to do with the fuel rail. What exactly did you do to the RB20 rail to modify it, and how easy was it?

[JimX]

I didn't modify it, I bought it pre-modified I'll take some pics this weekend. I will also draw up some plans for anyone wanting to do the same mods to an RB20 fuel rail. You'll need to cut the metal fuel return line off plus the mounting brackets, and put on 2 new ones of a different length.

From looking at it, I wouldn't want to work it all out myself before modifying. With a plan done up, it looks like it'll take a few hours with some sheet metal and an oxy welder. Less if you're good at welding.