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Hey guys,
I am currently redoing all the fuel system, as some of you will know, and fitting 1680 Bosch injectors, primary and secondary.
I have a billet primary fuel rail and some injector spacers/reducers to go in the engine but I have nothing for the secondaries as yet.
I was going to mod the stock one with some AN fittings each end until I realised the holes for the OEM injectors are too small for the Bosch ones.
I come up with some questions having stripped out the stock rails today.
I have included some pictures of what I have stripped out and wondered if anyone could confirm some things before I damage or remove something I shouldn't!
After removing the stock injectors are took out the rubber seal they sit directly on to find underneath there looks to be some other kind of seal or something? The seals I removed are in the bag in the picture below. One of the spacers/reducers I have to fit is also pictured with the o-ring on it. It looks like I need to pull out the bit I can see down inside the injector hole to be able to fit this properly. Is that correct?
I managed to get these second seals out of the secondary injector holes after a bit of a faff to see they are some strange plastic flow control or something. I got a picture of one below as well.
The ones under the primary injectors look like they might be similar but it is very hard to tell and I cannot seem to get them to move and I don't want to force it just in case something breaks and drops down or they need to stay in place! Please can someone advise?!
Also regarding the injector spacer/reducers I have seen two types. The type I have with the O-ring and a type that has no o-ring or step in the body. Just a plain short bit of tube? I presume the latter are a press fit but don't like the idea of no seals.. Can you use the sealed type for both primary and secondary injectors or will it not work and I need the plain set anyway for the secondary injectors?
Come one guy's... share the info.. all you 20B guy's must have been through it!
I also noticed, while test fitting the primary rail I have, that there are a couple of lumps on the casting of the LIM that stick out of the front and rear secondary injector bodies. These get in the way of the fittings for the fuel rail!
I am assuming you just cut them off as they don't appear to do anything.. Nothing is straight forward on this fuel system upgrade aye!
The plastic bits that you have pulled out are a diffuser, used to help atomise the fuel when injected. These are quiet old now and maybe brittle (good chance of them breaking when trying to remove them) if you are going to be using the old style Bosch injectors (as opposed to some EV14's) I would keep the diffuser.
I personally wouldn't fluff around modding the stock rails and just go with new rails. but if you must use the stock rails just ensure that the injectors sit firm down in the intake manifold and irons.
As for the lumps on the lim, they appear to be nothing to worry about and should be able to be ground back
Thanks for the reply..
I really wanted to be sure I didn't have to pull the diffuser bits out. A relief to know they can stay in as like you say I think there is a good chance of them breaking trying to pull them out and that would be a real nightmare! I have Bosch Ev-1's for ref. So I will put the diffusers I took out, back in. I was going to see a fabby about modding the rail or getting some stock rail billet to make one but I might just import one from Xtreme Auto in Aus unless anyone has any better suggestions?
To mod the stock rail shouldn't take long. just making sure the injectors sit snug enough might be tricky. I am guessing if they have a mm of float up or down it wouldn't be the end of the world as long as they cannot come unsealed? Pretty sure with a bit of trial and error and measurements off the primary rail I have I could get that sorted though. All swings and roundabouts.
That and the fact I like making my own parts where possible!
Looks like I need to take out the diffuser parts to fit my xtreme rotary injector spacers/adapters. I am using the old Bosch injectors but I am told they need to come out. Hopefully that won't cause any major fuel related issues?!
Anyone got any tips or tricks for removing these things? I managed to hook out the secondary ones okay last time bit the primary ones didn't seem to want to move?
01-16-16, 07:57 AM
