yet another turbo question, sorry! lol - Saxperience

saxo_girl_1985 · 18th April 2009, 19:34

so we all know what a turbo is,

turbo, all the pipework, intercooler, dumpvalve...

if a turbo is running a 5th injector..

i thought if running a 5th injector, that by passes the ecu..the 5th injector gives the turbo the fuel it needs.

do you still need mf2?

i read loads of threads and all have the mf2 or dasket, mapping on there turbo project lists...

just want to understand it a bit better,

and please dont be harsh...lol

Quick · 18th April 2009, 20:19

MF2 can control the 5th injector, telling it when to pump in extra fuel and how much.

Standalone is the best option (if you have deep pockets)

VtsTom · 18th April 2009, 20:28

You could use the Predator ECU. About £500. 4 larger injectors are about £160, job done. None of this faffing about with extra injectors and piggybacks

gixxa · 18th April 2009, 20:45

the mf2 is an ecu that controls the extra injectors, it makes the injector fire at different rates according to rpm.

With out one or another form of injector driver, the extra injectors will not fire

saxo_girl_1985 · 19th April 2009, 00:05

so without a mf2? if adding a 5th injector? the extra injector will not run??

or a mf2 can control the 4 main injectors, but tells them basically how much fuel to give out?

Sophia_Bush · 19th April 2009, 00:36

no mf2 does the 5th injector

standalone / dastek do the 4 bigger injectors

saxo_girl_1985 · 19th April 2009, 00:38

ok thanks i understand now.

Sophia_Bush · 19th April 2009, 00:40

if your stuck on anything chuck me a pm or saxmad/deeboyvts or dannygti

gd16 · 19th April 2009, 13:56

As Gav says, a 5th/6th injector on its own will not do anything. It needs to be connected to something that will tell it when to fire.

The MF2 is the piece of hardware that can tell it when to fire. By using a combination of RPM and pressure measurements, it can be mapped to control this extra injector and allow it to fire the extra fuel necessary for the engine to run.

Obviously the constraints are on how much fuel is needed and how much fuel the injector can spray. Ideally you don't want to be running injectors at more than 85% of there max capacity. Likewise, if you go OTT, a huge injector may be able to supply all the fuel you need - but won't have as much control at lower injection openings. Which is why sometimes you see people using 5th and 6th injectors.

As mentioned - standalone with 4 larger injectors in the standard position is the best route. A lot neater, and the standalone allows more control over other parts of the engine management. But it also is a lot more expensive. Really depends how far you're going to take it.

don55 · 19th April 2009, 14:53

std ecu will not run 5 injectors

saxo_girl_1985 · 19th April 2009, 15:54

thanks for the info, is the mf2 basically when connecting plug and play?? you do it urself,

rather than dastek, remapping where u have to take it to some one?

whats a sigcon?

can you plug and play a 3 map bar sensor?

gd16 · 19th April 2009, 16:40

You can install/map an MF2 yourself, but you'd need a decent AFR gauge in order to get the fuelling correct.

A SigCon is basically a Signal Conditioner. I think it was primarily developed for the 3plug ECU's to help combat a few issues they had when an MF2 was being used. The main thing the SigCon does, is trick the standard ECU into thinking that it is in a WOT state whenever boost is seen. Without it, i beleive the car can be a bit stuttery in the transition between boost/vacuum.
The other thing it does, is allow a non-standard MAP sensor to be used by the standard ECU - in so much that it ignores the wider readings, and just takes the readings from it that it would normally see.

3 bar map sensor you could use with MF2, but not with the standard ECU. The signal would need modified in order for the standard ECU to use it. What you can do is have the standard MAP sensor as well as the 3 bar MAP sensor running together - standard MAP for the standard ECU, and 3 bar MAP for the MF2.

liam_VTR · 19th April 2009, 16:53

probs abit of a noob question ... but where does this 5th injector go?

gd16 · 19th April 2009, 17:18

Really it can go anywhere in the inlet tract after the turbo or s/c. However, best is to have it just slightly down from the throttle body - pointed at the throttle body. Means its far enough away to mix well with the air, and also atomise better if it smashes off the throttle plate. You want it pointing with the flow of air obviously.

Not a great picture, but you can see where the 5th and 6th injectors are on my old setup, the beige looking things next to the master cylinder.

saxo_girl_1985 · 19th April 2009, 21:14

i like the pipe work...

liam_VTR · 20th April 2009, 01:23

Quote:

Originally Posted by gd16

Really it can go anywhere in the inlet tract after the turbo or s/c. However, best is to have it just slightly down from the throttle body - pointed at the throttle body. Means its far enough away to mix well with the air, and also atomise better if it smashes off the throttle plate. You want it pointing with the flow of air obviously.

Not a great picture, but you can see where the 5th and 6th injectors are on my old setup, the beige looking things next to the master cylinder.

Oh right ... i see now

cheers mate ...