Hello

Ive read on here somwhere someone is running 21psi by wiring his coldstart valve to a boost sensor that kicks in at x psi.

How much fuel does the cold start valve drop in could i get away with doing the above mod and running 18psi on std botttem end with just big intercooler?

I was thinking of doing the above mod and taking it to scc and get them to set it up.

Also what is the fuell pressure mod and will i need it for 18psi?

thanks Paul.

I run mfi rs turbo lump in an xr2

 

you can buy 5th injector drivers from stu at motorsport developments that use the cold start injector. You can program what psi you want it to kick in at and what flow rate you want, I think there about £125

The fuel pressure mod you are talking about is altering the electro magnetic pressure actuator on the side of the metering head, dont do it yourself, take it to somewhere that knows what there doing. Where are you based ?

You will only know whether you need a 5th injector once you have taken the car to a tuner, they will alter the EMPA untill you hit the limit, on mine I could run 17psi before I needed the extra injector.

As long as you have enough fuel and good front mounted intercooler then 18psi should be ok, I ran up to 25psi on my standard bottom end The standard rods are ok up to about 250bhp ish.

Hope this helps, Duncan

 

sound chears matey i am based in Portsmouth will scc performace in st albans be able to do this mod?

How does the fuel pressure mod effect econamy the thing that attracts me to the 5th injector route is that i would only be using extra fuel at high boost situations instead of having my car set up to dump lots of fuel all the time through out whole rev range which is what i am asuking the fuel pressure mod is?

 

i am running 16 psi approx 190bhp, which is all my fuelling can handle, i am getting 5th vinjector sorted to up the power 220/230 BHP

 

my car was running abit of boost when i first bought it seing hows i have no history with the car ie tuners receipts etc and the guy had no knowledge on it i have wound my bleed valve all the way back in making 14psi so probably was running 17-18psi but i dont want it to blow up or be on its fueling limits.

i have found the guy who is running the cold start valve as 5th injector and have pm,d him for abit more info.

Still a bit unsure on what the fuel pressure mod does for fueling throughout the rev trange and weather i should opt for this or 5th injector;-( any info much appricated

 

you have to make sure you can take more psi,
can your turbo handle it, do you have an uprated intercooler,
is your engine sound enough?
etc, etc

 

The 5th injector will only provide around 5% extra fueling so will only gain you a couple of PSI.

Stu's injector controlers will control a larger injector like a Cossie Yellow/dark blue or even a green injector. The difference between Stu's controlers and an MF2 is that the MF2 is 3 dimensional and can be set to come on at a certain rpm if the boost is over such a PSI etc when it starts to run lean. I don't know if this is still the case with Stu's controlers of if they have developed them further. They also make good water injection controlers.

My car has been set up to run 14psi but runs lean at 5krpm so can't rev it passed there. The fueling has been wound right up and I either have to up the fuel pressure, get a 5th injector or ditch the whole system for something not prehistoric! KE-Jetronic on my car can only supply fuel for the whole rev range with the boost set at about 11 psi. It just can't cope without more indept modifications.

I advise you get the fueling checked by a tuner before you do anything....

 

if u go to a decent tuner and your metering unit is in sound condition my fueling is fine on 21 psi with the fuel pressure mod, it wasnt without it!, get it setup on a re-mapping company which sets your car up on road loads,

had my car off the clock the other in a very short time didnt pink or knock at any stage, a credit to apt,

turbos blown up now so thats at pts now!.

 

I hope that is aimed at the topic starter.

My engine consumes far more air than a standard CVH will which is why it runs out of juice at such little boost even on a standard turbo...

 

it might be me wh0 you saaw the link about cold start injector,
ive been runnin it like that for nearly 3 yewars at 21 psi, no props yet,

 

If I remember well, raising fuel pressure of the KE-Jetronic will deliver about 5-7% more fuel throughout the rev range, so fuel comsumption will rise with that one.

You can buy an (adjustable) switch, which is pressure sensitive and could start the cold start injector at a certain boost level.

To be able to check how the engine runs, one could opt to mount a lambda sensor in the exhaust and connect it to an air/fuel gauge. Then you will always know if the engine runs lean, rich or "normal". Could be very interesting in case of tuning plans

Cheers

 

zvhrst i think it was you as the guy i emailed is runing fuel pressure mod only, that lambda sensor idea is good apparently one that is half decent and gives acuret reading will cost allot thoe can anyone recomend me a cheep gauge and sensor that will actually work and not give dodgy readings?

I have an xr2 with escort rst lump will there be a mouting for it or will i have to get my downpipe modded?

Also if i am getting one welded in where do i want it back box or downpipe?

I was thinkning back box would be allot easier plus i could take it out and maybe use the tappd whole for another device

 

the lambda sensor needs to go as close to the turbo as possible!, and u need a wideband one for accurate results!

 

chears Grimme

Anyone got any rough ideas as to how mucha wideband sensor will cost?

and the nessasary fitting bits?

thanks Paul.

 

alot of money when i priced one up, think around 300 quid with the meter and wiring, there simple to wire in.

check ebay normally some on there

 

the MF2 is a decent bit of kit when one uses a 3bar map sensor, the more air being sensed by the map sensor the more fuel gets injected(equally matched), using a yellow,grey,green injector , up to 4 injectors too.
my guess the mf2 can provide at least 10% xtra fuel (using 1 injector)
another benefit is the KE can be kept standard,or just a small amount of increase in current at the EMPR ; so less fuel to be spilled, better economy and performance.

 

Arjan the mf2 sound like just the thing im after so i can keep ok oconamy but have fuel for when i need it.

How much does the mf2 cost and also how hard is it to get set up?

Thanks Paul.

 

- The MF2 is based on an open-architecture design, which means that the unit is freely re-programmable at any time, open to any one who possesses a small screwdriver: no computer interface is necessary! If this interests you, read on ... working alongside the original ECU, the MF2 controls its own set of injectors, four high-impedance injectors and two low-impedance injectors (not supplied). It is able to use the signal from the existing sensors, or it can operate independently. 3D-mapping is simple if a load- or pressure- signal is fed into the unit.

- for applications where load signal (throttle angle sensor) or manifold absolute pressure sensor (MAP sensor) is available, the pressure can be used in conjuction and enhance the 3-D mapping.

- An additional pair of wires supplies a stablised output voltage of 5 volts for driving a MAP (manifold absolute pressure) sensor.
Voltage converter IC
This little integrated circuit converts the incoming +12 volts DC supply to +5 volts for powering optional Manifold absolute pressure(MAP) or optional Throttle angle sensor

- The injector plug comes complete with mating pins and splash proof seal, which enables direct conection to a BOSCH type fuel injector.

- Eight half-turn potentiometers (clockwise for more fuel) provides enrichment curve at 1000 rpm intervals and are electronically interpolated to give smooth change-over points. Factory preset at 1/4 turn

- input gain potentiometer
25 turns gives full pressure input gain (factory preset at 12T) when used with manifold absolute pressure (MAP)sensor or throttle angle sensor within the 0-5V input range.

- Pressure threshold potentiomater
25 turns sets the full pressure input signal cut-in point (factory preset at 12T).


------
thats all info i could find
for the full guide : http://www.aquamist.co.uk/cp/mf2/techmf2/mf2tec.html


its not so hard to set it up when u have a wideband lambda installed on yr car(with logging capabilities), that way you can set it up nicely, i would call it an investment, and gives YOU the control
or go to a good tuner to have it set up for you.

the kit (excluding map sensor and injector(s)) costs about 200 pounds.


edit : the TechEdge wideband costs about 320, http://wbo2.com/2b0/default.htm

 

got my 5th injector today

 

You'll be back up to Stu's soon again then Andy?

 

A lambda sensor needs a hole in the exhaust and a nut welded
on top of the hole.
Then connect the sensor to the air/fuel gauge.

The sensor could be non heated, this one needs to be near
the exhaust manifold because the sensor needs at least 400 degrC
to work properly.

The sensor could carry a heating element, in which case
the sensor could be placed further down the exhaust.

Most advanced option (and most expensive) is a wide band sensor.

I don't think you need a wide band sensor, the sensor just
measures the O2 in the exhaust gasses.
Before the wide band existed, engine management
systems worked very well with the other types of sensors.

So I guess any lamda sensor could do the job, they do need
to be in good working order of course.

Cheers.

 

i run the cold start injector fromboost switch which gives me aprox 5-7% more fuel as said above, then took it to top gear performance and they turn the whole ke-jetronic unit up thus giving me around another 4-5% more, i running jus over 280 bhp, at 21psi, fuel does lean off towards top end tho, but respecting that my cardont rev past 6k it dont worry me

 

ke jet can fuel a lot - it's just calibrating it thats the problem.

IM going for the mf2 for now - even with a yellow u can get an extra 65hp

 

any ideas how the regulator is adjusted.

 

it shouldnt....

 

why not? if it can be adjusted for more fuel with out. are you saying that you should just fit a 5th injector and thats that.

 

Upping the fuel pressure is a last resort scenario. It will write off any chance of having any form of fuel ecconomy as well.....

 

my fuel economy hasnt changed on my turbo and i had the fuel pressure mod last week with a boost hike to 21 psi!.

its cheaper to have the fueling there when you need it, than not all and having to replace engines due to damage caused by running lean, and who nowadays buy a rs turbo for fuel economy? when u have a rs turbo running over 200 bhp what chance do u have or expect to have of fuel economy?,

if u spend thousands on engine rebuilds ie pistons and big intercoolers etc u should afford to run rs turbo, if not buy a diesel!! and run it on red!!.

 

decided to get rid of the ke jetronic sounds like too much messin about. might as well put cos style management on.

cheers anyway

 

i agree with grimmeRST

 

If you can afford thousands in engine parts, you should beable to afford proper tuning.
When your doing the fuel pressure mod, is the fuel pressure increased all the time, or only when your in boost?
Running rich all the time is'nt healty either.

 

it isnt rich! its spot on to the boost i run,and my car sucks air in more than most rs turbos due to my mods so i have to match the air to fuel, like someone said earlier the KE can flow enough fuel up 240 bhp with the right mods, i also have a higher pressure pump aswell....

cars may appear rich on a dodgy rolling road tune, get it wideband lambda tested going down the road with a tuner like Stu's place in blackpool or APT in Norwich which use the latest equipment under proper conditions and u will see!.

Most tuners will put a bit more fuel in on top boost anyway.

 

What a great topic

The EMFPR on the Bosch KE system is a global modifier.
When you increase the pressure you increase it everywhere.

The problem you run into, is the point where you have to decide, where do we go from here? You can have more power and terrible economy, along with the other side effects of excessive fuelling, or you can find ways to add supplementary fuel.

I personally advise customers to go for the additional fuel supply injectors or better management so as to maintain off power economy and maximum engine longevity.

The 2 types of controller available are quite different in their properties. mappable and fixed. The fixed type is used primarily where we require a nice midrange spike but dont want to up teh whole pressure system to cope with that boost. In this scenario i will set the boost to say, 22peak and 16held. For this, the fixed injector will switch on at 17psi and fuel for the 22. That way the system can be left to cope wth the power produced by 16psi, and still make good midrange torque through the spike.

The mappable injector has already been nicely covered

Please all take note:
Boost pressure means nothing. Airflow is all that counts as far as fuelling goes. Even a worn camshaft can make the difference between 22psi and 16psi making the same horsepower. Big Boost just means for some reason the air you require cant get into teh cylinder easily and you possibly could be spending your money better elsewhere.

Hope this helps.

 

Now lets talk about Dave E's old car

 

[quote="Stu @ M Developments"]What a great topic

The EMFPR on the Bosch KE system is a global modifier.
When you increase the pressure you increase it everywhere.

The problem you run into, is the point where you have to decide, where do we go from here? You can have more power and terrible economy, along with the other side effects of excessive fuelling, or you can find ways to add supplementary fuel.

I personally advise customers to go for the additional fuel supply injectors or better management so as to maintain off power economy and maximum engine longevity.

so would you recommend me to get a stand alone system with cos greens as i want maximum power wtih the current 1600 stg 3 and when that blows i`ll be going 2lt. from what i`ve made out from various posts the ke is a fooker to adjust and maintain correct adjustment. plus with the increase in capacity and large boost the bugger will be leaner than an anorexics ass.

basically i want it to run right and i`ve heard the ke is the source of a lot of problems with turbos. what would you advise me to do. as i`ve priced up the mods to ke to get the power i want and the stand alone cossie style management isn`t that far off the price. also could you tell me what power std 4wd cos injectors would be good for powerwise.

cheers, flax.

 

ok guys some good info here

I think i would like to opt for this option, have the car set up to run 2 differnt boosts ie hi and low.

on the low boost i would like the ke fueling set up for this all the time say 14psi im hoping that this means i could get away with near on std fueling just tweeked alittle to save fuel.

Then have hi boost say 17psi which is activated by boost activated switch at 15psi and use the cold start valve for this

How much extra fueling can you get out of the cold start valve somone mentiond %5-7 how much psi would this equate too?

In an ideal world id like the boost to be set as hi as std fueling can fuel ie 12 psi without raising fuel pressure so fuel econamy is good then have a cold start valve that fuels for extra 5psi when needed is this possible by running a bigger injector in my coldstart valve?

Thanks Paul.

 

yes, i went down on saturday

i have the MRL 5th injector soon to fit, any one know a company who
does a crossover with a bracket for the 5th injector, i would like it to
look neat and to be frank, i dont trust myself to do it. i know the
Astra GTE has a suitable mounting bracket for one to tig onto crossover
but the are quite scarce.

cheers

 

The placing of the 5th injector is important. The extra fuel needs to get distributed to each cilinder in the same way, otherwise 1 or more cilinders could be running lean, while others are OK.

 

ATT DODGYDOWG
I RUN 17 PSI WITH TWEEKED JETRONIC, THEN FLICK SWITC TO RAISE BOOST TO 24 (HOLD 21) WITH TE BOOST SWITCH SET TO 18 TO KICK IN THE COLD START INJECTOR, I RUN 285BHP, HAD CAR SET UP LIKE THAT OVER A YEAR AND MY ENGINE STILL FINE