Zetec injection question
 

Early days for me & my 1.8 Zetec install but I have a bit of a dilemma over the injection method. :confused:

I'll start from the beginning.

After almost 2 years of worrying about engine choice I finally opted for the 1.8 Escort Silver top Zetec engine.

I will be using the Megasquirt ECU to run the engine.

I ended up with 2 sets of throttle bodies. CBR900 R1 & CBR900 R2. ( Long story ) :o

After a bit of reading & a nice chat with Martin Jeffery ( Engine tuner )
It would appear that injection, directly into the head is a little more effective than injection into the thottle boddy.

As the Zetec has a separate injector rail, both options are available when I make the inlet manifold.


If any members have chosen the Zetec + throttle body combination, I would love to have your input. :) :)

Ronnie

It's reasonably easy to do both. After a fair bit of research, I decided to use the injectors in the throttle bodies, as the performance difference is marginal on an otherwise standard engine. It seems to have more effect on torque tahn power, and having the injectors in the manifold tends to bring the power band slightly down the rev range. For high states of tune, this will make more of a difference, but as I say, for reasonably standard engines, it doesn't make a lot of difference. It's far easier to make yourself a manifold if you keep the injectors in the throttle bodies, as then you're basically looking at a flange and four tubes. However, if you decide to go with injectors in the manifold, an ST170 manifold has injector mounts, and also 4 useful stubs to mount your bike bodies onto. Been coverd many times on various websites,a nd I'm sure you've already Googled these!. Just beware, if you're not using the manifold on an ST170 engine, the manifold doesn't line up as exactly as some would suggest, and to get the best out of it, you'll need an adapter plate to address aroughly 10mm step between manifold and head.

Hope that helps!

Cheers

Adrian

Cheers Adrian :)

Martin Jeffery did say it was rather dependent on how far I am looking to go with the engine. ( Power wise that is. )

To be honest if I manage 140 BHP without too much expense I would be quite happy. ;)

The 1.8 Escort is listed at 115 BHP as standard. Perhaps if I fit a pair of 2 litre cams & a good tune with with the megasqiurt then I should be near the mark.

I have been unable to find any data on the flow rates of the Honda injectors. :confused:

Have you any data on them Adrian ?

The Fireblade R1 bodies are from a 929cc engine ( Black injectors )

The Fireblade R2 bodies are from a 954cc engine ( Green injectors )

I'll have a look for you Ronnie.

I've got a 2l Silvertop, and I'm hoping for 165-170 bhp with bike bodies and a decent exhaust (plus of course the megasquirt map). Think you may be pleasantly surprised with your expectations!

Cheers

Adrian

Cheers
 

Thanks again Adrian :)

I did find a small amount of info on the MS forum, mainly guestimated flow rates based on BHP produced by the original engine.

My searching was interupted buy a new search. :rolleyes:

Trying to find the operating range of the IAC stepper motors that I have found.

When I built the Megasquirt I opted for the stepper motor idle control as opposed to the original ford type idle control unit.

I did find a couple of stepper motors in self contained units that are ideal for the job. Rover K series unit & a Renault unit.
All I have to do now is find the tec data on them. :)

Took mine to bogg brothers yesterday and achieved 160hp at the wheels for a 2.0l blacktop, zx6r carbs + megajolt. All for £400, very pleased...:)

Cool
 

160BHP at the wheels is good going, only costing £400 too :cool:

The engine tuner that done the mapping on my eldest lads scooby is quite familiar with the Megasquirt system so loose plans have been made to give the car a final mapping once it is complete.

With a little luck I will able to get things somewhere near the mark ;)

Bike carbs & Megajolt are my plan B if things go pear shaped with the MS & Injection. :D :D

Ronnie

Where are you going to plumb in your IAC Valve? I was wondering about going without, as the CB900 bodies have what is in effect a choke cable that I could use instead, but it does seem abit at odds with the control you get with a mapped system to then have a 'choke'.

Hmm, not sure!

Cheers

Adrian

hi spud
bogg brothers are they daves sons if so has dave retired now?
thwang

Hi Adrian.

Yes the CBR throttle bodies do indeed have a wax-stat auto choke.

I have no idea how it would function in conjunction with the MS ECU though. :confused:

I have stripped the chokes from one set of bodies & think it will be easy to adapt them for the air intake pipes from the IAC unit.

I suppose they could also be blanked off & the extra intake pipes placed into the inlet manifold stubs.

I'll try & get a couple of pictures up of the IAC units I have found. :)

It would be a good idea to try to post a sketch or two to show how I intend to set up the IAC system. ;)

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

CBR900 Fireblade throttle bodies
 

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.

Proposed Throttle body mods
 

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 :eek:

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. :D
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 :D

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.

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