Zetec injection question

[adrianreeve]

Ronnie, mine are slightly different I think. They are from a CB900 Hornet rather than th CBR900 Fireblade. The choke is actually a manual device, with it's own cable that could be routed to the dash. I'll have to do some more research here, as I'm guessing it worked fine with the ecu on the bike, so there must be way to do it.

Let us know how you get on with yours.

Cheers

Adrian

[Bonzo]

Heres a couple of pictures of the throttle bodies that I intend to use on the Zetec engine.

Honda CBR900 Fireblade R2 954cc engine in the region of 150BHP






These are fitted with a wax-stat type cold start/idle mechanism, controlled by water temp. The cable is for fine adjustment.

[Bonzo]

Another picture of a set of Fireblade throttle bodies once stripped



As explained, I would like to try and use an Air Intake Control stepper motor (IAC) to assist cold start & engine idle.

Here are my proposed changes

The red dots are where the original air by-pass plungers were removed from.
It will be simple to replace them with fittings for air intake pipes.

The Yellow dots are where the exsisting air intakes are. These will need to be blanked off. Not so simple but do-able.

The IAC unit is the Black thing with the 4 wires.
I have drawn the proposed air intake pipe set up.

This AIC unit came from a Rover K series engine & would be quite simple to adapt in order to fit to the main air intake pipe or filter box.
The main air intake area is marked in Blue.

Oh, & make a manifold to suit

[adrianreeve]

Good idea Ronnie, I reckon that will work! As I thought, mine are slightly different, in that the cold start mechanism is purely mechanical, no connection to water etc, just a plain old pulling mechanism. I'm fairly sure though that I could do a similar mod to you, as stripping the cold start valves out would leave me with what you have. At the moment though, I think I'm going to leave it as is. The general concensus on the other side seems to be that IAC valves aren't that necessary with bike bodies, so I may just see if I can do without for now.

Started properly on the manifold today. If my broken camera fixes itself, I'll post some piccies at some point.

[Cobra289]

Hi,
Just an opinion.
I think that those bike TB are not the best way for the Zetec engine.

Check the position of the injector at the Ford manifold, they spray exactly at the inlet valves.
I have a sectional drawing that confirm that. At the other hand the TB of the bike will never locate the injector correctly.
On top of that it has a lot of parts that can goes wrong and also are difficult to balance.

So I will advice if you haven't buy the TB jet to reconsider the setup.

Make a inlet manifold wit a single TB will give you the same performance although most people think that complicate things is better.

The initial problem arise from the available space in some kits, so there are solution to solve that problem without go that difficult way.

As an example I post some picture of a Opel engine with such manifold.
Just 4 trumpets with the injectors located at the right spot, those protrude the main plenum, underneath the trumpets there is a slit that communicates with the inlet plenum [distribution plenum] and at the front the single TB.

Easy to fabricate etc. the rest of the components like IAC remind the same only it needs to bypass only one TB.
Some of the TB have the IAC integrated in the cast and an very small.

Here is the picture of the Opel inlet manifold, but we will use the Zetec 2.0L engine in our build. [Change the plans]



I haven't finish the Zetec 3D design that is why I could show you the same idea but at the Zetec.
But here is a picture of the Blacktop as far I am on the design.



Regards,
Cobra289