Bosch or Denso Style injectors?
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Joined: Sep 2005
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From: Smiths Falls.(near Ottawa!.Mapquest IT!)
Bosch or Denso Style injectors?
I just want to Double check on this.
3 kinds of RC Injectors( obviously not Honda) .
IF my memory is working right.,do I use DENSO style injectors on my TII Stock Secondary Rail?..or Bosch?
I am going Bigger....again..
Thanks Guys,STYX!~
3 kinds of RC Injectors( obviously not Honda) .
IF my memory is working right.,do I use DENSO style injectors on my TII Stock Secondary Rail?..or Bosch?
I am going Bigger....again..
Thanks Guys,STYX!~
The short answer is, use the Denso style. Now, a fuller explanation: the Denso style are factory and are kind of like this:

They have a narrow top and a wider bottom with a bigger seal at the bottom. The bottom seal isn't really an o-ring... it's more like a flat rubber seal. Bosch style have the top and bottom as the same diameter, and use a true o-ring at the bottom.

If you try to put a Bosch style injector in using completely stock parts:
1) it won't fit at the top (stock fuel rail) without modification because the o-ring bore is too big, resulting in a fuel leak.
2) it won't fit at the bottom without modification because the o-ring isn't the right size to seal, resulting in a vacuum leak.
For anyone else who may be wondering, if you have an aftermarket secondary rail (KG, whatever) a Bosch injector will fit at the top. But you have to install an s5 pintle cap (must be S5, available from Mazdatrix) on the bottom and use the factory grommets.


They have a narrow top and a wider bottom with a bigger seal at the bottom. The bottom seal isn't really an o-ring... it's more like a flat rubber seal. Bosch style have the top and bottom as the same diameter, and use a true o-ring at the bottom.

If you try to put a Bosch style injector in using completely stock parts:
1) it won't fit at the top (stock fuel rail) without modification because the o-ring bore is too big, resulting in a fuel leak.
2) it won't fit at the bottom without modification because the o-ring isn't the right size to seal, resulting in a vacuum leak.
For anyone else who may be wondering, if you have an aftermarket secondary rail (KG, whatever) a Bosch injector will fit at the top. But you have to install an s5 pintle cap (must be S5, available from Mazdatrix) on the bottom and use the factory grommets.








