Fuel Injector Recommendations (GENERAL EFI INFO)!!!
Turbo Mini Forums

Just had a read through this.

I assume the problems with the DTA you used, were due to it running batch fire only ? My P8Pro can run proper sequential, and you can adjust end of injection.
Based on that, would the P8Pro be an option ?

When I first got the Haltech E8 ecu's I used recently, I thought the EOI angle they seemed to use was a little weird, with most base maps being set at around 330-450deg BTDC

I thought, surely this will fire against a closed valve ?? and yes.
Apparently Motec also prefer this route.

I would have thought myself, that firing whilst the valve was open was the correct way to do things, and is apparently what Bosch imply in their blue book.

Perhaps in the real world it doesnt matter so much ( at least on 4 port cars ) Both Subaru and Cossie are running fine, Subaru with 400BTDC at 0rpm rising to 500BTDC at max rpm.
I did alter the Cossie admittedly, its at 270 rising to 360 BTDC

If you were to time EOI to fire before the inlet valve opens, would that fix the charge stealing issue ?
It sounds like thats almost what you are trying to do, finish injection, before the "robbing" valve opens ? Except I think you are implying you still intend to open the injector only when the correct inlet valve is open, rather than before it opens ?

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

I know how the P8 works from a mates mini - but I still don't think it'll do everything needed - BUT - no harm in not giving it a try.
Start of injection, and swinging the injection point about is the first step - AND - having the injectors as close to the valve such that the dynamic injection start point changes little (with reference to crank position) for all rev ranges; that's to say the time between the fuel leaving the injector and reaching the valve is as near as dammit the same for all cases.

BUT - don't mount it so close that fuel 'puddles' on top of the 'inactive' valve...

From there on in, you're on your own...

Is the charge robbing scenario more of a problem at low rpm's or at higher ??

Was having a read through here, which has shed some light on the matter for me
http://www.emeraldm3d.com/em_projects_Aseries.html

I also read throughout the forum....

Rover have an "injector per port" system with 2 injectors.
Obviously this cant be sequential, so how do they get around the problem ?

Surely running a setup like that will make matters worse than a 4 inj sequential system ?

9.85 @ 145mph
202mph standing mile
speed didn't kill me, but taxation probably will

The Rover MPi system used two (total) 460cc injectors - one per inlet port - which were fired sequentially; sequentially in that when the port was 'active' the appropriate injector was firing.

They weren't firing sequentially in that injector A fired, then B, then A, then B, etc... It was AABBAABBAABBAABB.....

having read carefully what's involved in injecting the siamesed 5 porter since some time, I've run away from this and collected parts to use twin carby...
then I now have access to an mpi complete set up which I would like to use in combinaison with an emerald unit:
the mpi mems will deliver fuelling at anything under boost , then the emerald unit will inject a "laser beam" fuell stream directed precisely at each valve tulipe, using some 42lb lucas disc type injectors , the mpi unit should give enough fuell for 80 bhp, waiting some 150/160 one out of mine I would only need requirement for 80 bhp which could fall into the tiny injection window.
what's your though please?
fab

Unless you can ensure the Emerald doesn't fire till after 40-degrees ATDC, then you'll start running into probs Fab. You also should set up a table showing max injector pulse, so you know when not to increase the pulse width any more.

Even if you inject directly at the intake valve if the timing is such that you inject on a closed valve for the outside cylinders, you will get some of that fuel to the inside cylinder. The fuel that hits the hot intake valve will vaporize and the air entering the inside cylinder will draw in fuel vapor from the outside intake port.

I'd be interested to see the actual results but I think you won't be satisfied with the outcome. You could try the new Megasquirt code but it will require some experimentation.

Si tu désires plus d'information sur le code, tu peux me contacter directement.

Jean

http://www.jbperf.com/

thanks for inputs ,
I see what you mean by the robing of charge , inner cylinders opening just before the outer ones are closing, so timing is critical.
the idea was to simplify the fuel delivery in dividing the trouble by 2, but it seem that it'll need some more work in waste time that I can give , Dave walker also emailed that it'll be difficult to sort :( ... .
I would like to be in the party, but can't anymore, family first
I'll keep an eye on your progression and hope you'll agree to share some information to convert the carbs to efi later
regards
fab
et merci Jean pour cette petite phrase en francais, je te contacterais avec plaisir dès que j'aurais avancé dans mes projets

Hi,
Fab .. I'm thinking of doing the same, only my plan was to mount the extra injectors before the throttle body. I'm going to use the Mega squirt to fire the extra injectors, so I can remove the Rover ECU when the code is sorted.
Cheers,
Gavin :)

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Oh and regards the Rover Siamese Port Code, it was actally undertaken by Lotus Engineering, as they also did the Metro Turbo.
On 16th of Feb, 2007 shortly after the above BS was typed, TurboDave said:

You are full of shit. Click below for proof.


http://www.davecoxon.co.uk/Youve_been_served.jpg


They own the patent, but whom undertook the work?

Lotus.

IP is determind, prior to prject commencement.

Incdentaly have noticed they all swear a lot on this furum, seems like no moderation. Must not let my childern in the room when am veiwing!

Michael Theaker - a Rover Employee who left ROVER to work for Ricardo engineering consultants did the work. I have communicated with Mike in the past. I am pretty sure you haven't.

It is safe to say, that your credibility (and you're dragging Mtech down further with each post) on this forum is low. Why not quit whilst you're behind loser?

On 15th of Feb, 2007 at 07:51pm fab said:
thanks for inputs ,
I see what you mean by the robing of charge , inner cylinders opening just before the outer ones are closing, so timing is critical.
the idea was to simplify the fuel delivery in dividing the trouble by 2, but it seem that it'll need some more work in waste time that I can give , Dave walker also emailed that it'll be difficult to sort :( ... .
I would like to be in the party, but can't anymore, family first
I'll keep an eye on your progression and hope you'll agree to share some information to convert the carbs to efi later
regards
fab
et merci Jean pour cette petite phrase en francais, je te contacterais avec plaisir dès que j'aurais avancé dans mes projets

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

yes Robert your right, it's inner then outer.As writen by dave it's easier when you rearrange the numbers:with 2,1,3,4
reg's
fab

Every day is a school day ...........

How fast and how expensive ...... the same question...

I just found this site thru a link on the Megasquirt site.

Regarding the original post and sizing of injectors on motors.

I put together a spreadsheet that calcs the injector size for almost any injected motor. The yellow cells are unprotected input cells. Pink cells are critical output cells. The math logic is shown on the lower right corner. I has been proven to be close for almost any motor from 2 stroke watercraft thu full blown pro rally cars.

Have fun tuning

http://www.ncs-stl.com/fuel/ReqInjectors03.xls

AW

Useful spreadsheet.

However, warning for anyone using the MS Siamese code.

Maximum duty cycle should be set at 20%.

Also put in double the amount of injectors. This is because each injector does twice the amount of work.

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

So you should simply put 40% duty cycle and the correct number of injectors which is more representative of what is actually happening: each injector duty cycle will be up to 40% but that will be for 2 cylinders.

Jean

http://www.jbperf.com/

True

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

can we mix and match high n low impedance injectors? with MS3X

use a high impedance small cc injector and a large main low impedance staged in when the little one runs out

this would be one small one big per runner

http://www.jbperf.com/