108 replies to this topic

[DaveCoxon]

MPi injector...











You can see the logo pretty clearly in the top picture...

[MRA]

Has anyone tried raising the injection pressure ?

[DaveCoxon]

Yes, peeps have.
Raising pressure does two main things:

1)It reduces the 'flow' from the pump - so the benefit is lost or compromised - basically not as much as you'd hope. 3 to 4 bar is only somet like a 5% increase in flow aswell.

2)It increases the operating time of the injector (not by much, and an extra 1-bar sholdn't make a big difference, but it all adds up.


Biggest thing with MPi is how to then take fuel 'away' at lower RPMs and idle... As the MEMS can't be mapped, you're left to using 'interupter units' that are basically a bodge - and not overly acurate.
Increasing the baseline pressure on an aftermaket system is the best way - but then you have a problem of running such large pressures at idle; along with an injector you've compromised by running such large pressure - hence will not be stable in its opening. Basically, you'll end up struggling to meet emmisions targets.

I'm going to be using two modern (special) injectors per inlet tract and using the injector sequencer ECU to 'stage' the units, such that at idle only one is working, but then it switched to two (per inlet tract - four overall) at a set point. The injectors i'm looking at are huge flow, so will (hopefully) provide enough fuel for 18psi at 7000 rpm. I'm building an injector test-rig first however - to see how well they ACTUALLY perform in real life, rather than on paper. This'll make-or-break the project in my mind. If it's not do-able, it's a seven-port.

[AlexF2003]

They run out of puff above 170bhp, T2s that is....

But then again how many bhps do you want?

lol

Alex

How much earlier do they come on boost when compared against a Metro T3 ?

That depends on your induction system length and the cam you use....

Alex

[DaveCoxon]

Hey Alex - what are the injectors the cossie boys use nowadays instead of the antiquated Grey then? (save me registering and searching on the blue-oval forums) :wink:

[MRA]

That depends on your induction system length and the cam you use....

Alex

Hi Alex,

I should have said for a typical engine build, i.e. someone who has built up an engine with a T3 (metro) then fitted a T2 (one of the T2 family anyway) later on ??

:grin: :grin:

[Sprocket]

Found this

http://www.endless-s...25&bid=12&mid=6

[DaveCoxon]

Found this

http://www.endless-s...25&bid=12&mid=6

Hmmmm









They look remarkably like the Rover injectors to me!!!

[DaveCoxon]

HOLY C**P!!!


Endless Sport Injectors - 440cc Hi Impedence 4off £195.00ea (total) £780.00


what the hell???

£195??? that's double the Rover Price!

£780 for FOUR Rover injectors!

[Sprocket]

http://www.joeblowra...512a4d3af4049ae

And they are Lucas, not NipponDenso

Edited by Mini Sprocket, 18 December 2005 - 09:36 PM.

[mini_me]

Most my mates run yellows/803s on the cossies and rs turbos (with management and a 3bar map sensor) but theres a few of us who'v tried the 2.2 astra turbo injectors and found they have a much better spray and are infact more economical and can in fact help produce more hp but it all depends on the engine spec.

Cheers! :grin:

[DaveCoxon]

Holy C**p!

EIGHT injectors for under 200 quids!

That's more like it!


Good detective Work Sprocket!

[Sprocket]

Holy C**p!

EIGHT injectors for under 200 quids!

That's more like it!


Good detective Work Sprocket!

HOLY C**P!!!


Endless Sport Injectors - 440cc Hi Impedence 4off £195.00ea (total) £780.00


what the hell???

£195??? that's double the Rover Price!

£780 for FOUR Rover injectors!

LoL

Lots of exclamations mate

[MAGA7INE]

sorry to thread hijack but i felt this might be relivant, would there possably be a way to use a garrett gt-15? it is a fairly small turbo i am thinking of experimenting with one of these.

Yes, these are ideal for the 998 turbo or 850. 12psi on a 998 is smack on the central efficiency island of the GT15 compressor map! Will be boosting from 2k rpm, which is nice for torque.

Your biggest problem will be fitting it. I have mocked this up and almost finished an adaptor fitting for the metty ex manifold. My biggest concern with this is the rapid change in cross sectional area from the T3 manifold to the tiny inlet on the GT15. You have to neck it down from the rectangular ex man to a 30 ish mm hole. I have done this by taking a lump of steel, machining the sides off to leave one 4 bolt flange for the manifold and for the 3 bolt GT15 end.

Then the block is clamped to the turbo and bolt holes marked then drilled. You put the studs on, then take a gasket template in cardboard off the GT15, punch the hole through the inlet and mark up the centre point of this hole. Clamp the adaptor down on a pillar drill and drill a small diameter pilot hole then enlarge this in stages out to the actual size of the GT15 round inlet hole.

Then repeat the process on the T3 end of the adaptor of gasket, marking etc and use a head porting tool - air grinder, dremel etc to open this rectangle out and neck it down to the GT15 round hole. You then end up with a solid steel adaptor plate that will speed the gasses up nicely from the metro turbo ex manifold up to the GT15 and spool it VERY quickly.

I am making one up for a friend of turbominis and another one for the editorial 850 turbo, (936cc - 998 block, 850 crank, custom thrusts, 60 thou overbore, etc...). There will be a full article on making this in the new magazine in the future. Hope this helps!

[Sprocket]

What about turbo SPI?

Any one?