RadT

I need pics and info on aftermarket secondary fuel rail installation ???? I need help or visual on proper install. I am in the middle of putting my secondary fuel rail in but will not sit right on fuel injector hole going into Lim. Wondering if any buddy has info on o-rings i need or what to do? Bosch 1600 cc injectors and rotor sports secondary fuel rail. 3rd Gen 13b

Turblown

iTrader: (12)

You need LIM spacers. They are a machined spacer that you press in to the lower intake manifold. KGparts.com has them...

RadT

I bought the spacers from dave newbern but they recess into the hole to deep for the injectors and do not stay tight. His instruction also says to remove difuser. Dont the difuser help promote more spray for mixture?

GoodfellaFD3S

iTrader: (213)

You have a lot of searching ahead of you. Do not use the stock diffusers, and IIRC some people use a very short length of fuel hose as a spacer to place the injectors in the right spot.

If the fuel rail is from rotorsports, why not call them up directly to get tech support?

NewbernD

iTrader: (1)

It must have been a while.. I haven't sent out many sets lately. But glad to help. Most secondary fuel rails for the FD have a height that expects your injector o-ring to sit directly on the shelf here:




All these spacers do is to "shrink" the bore a little bit to give the injectors something to seal to. The o-ring still sits on what is left of the lip at the bottom but it is now sealed in the smaller bore and won't flop around.





They do not need to be very tall.. in fact they don't need to be much taller than the o-ring because that is the only part doing any sealing. They should definitely not be tall enough to touch the injector body if that is what you are expecting.

Because this is bore is drilled with a little tolerance from the factory, it is impossible to machine a bushing that will yield a press fit in every bore without having your LIM to measure. Some wind up being tight and some are a little loose. You can apply a film of epoxy or RTV to the outside of the bushing, press it in and let it cure. I would do this anyway for a permenant install.




And yes, diffusers help to atomize the fuel. But they have to go.. I think early experiemnts to keep them had led to them breaking off in the engine, perhaps due to modifications.. perhaps due to increased fuel being thrown at them, perhaps due to age.


Let me know if you have any more questions.

..dave

RadT

would you use a second oring on ejector shaft to help push down the first oring?

NewbernD

iTrader: (1)

If your injectors and o-rings are in good shape, I would not. Just lube the o-rings up with oil and push them in. Don't dry fit them or you can tear the o-ring. It's a tight fit.

RadT

Do you know what color stock wire go to what on the injectors? I did'nt know it was you that i bought the spacers from. I installed them last night and just waiting for them to cure. i bought these three years ago while I was in Japan. Thanks they look great.

killerrx710

iTrader: (8)

Would u have to take the diffusers out of the stock primaries also?
I'm building a single turbo with 1680cc sec and 550 prim.

GoodfellaFD3S

iTrader: (213)

If you're using stock prim injectors I would order brand new diffuser plates and grommets. Old ones can and will break off and destroy your motor, I've seen it happen four times now.

For mazda oem parts, Ray Crowe at Malloy Mazda is your best bet, 888 533 3400. Ships fast and cheap, good rx7club discounts, and the man owns an FD and knows them inside and out