Mi16 To Gti 6 Injectors

[craig_007 1]

I just fitted my Jenvey bodies and Lumenition ecu (Cheers Baz)

 

This was originally mapped on yellow MI 16 injectors but when I fitted them I used green GTI6 injectors.

 

Would this cause overfuelling on idle ? My AFR gauge is reading 10 constant on tick over and car is stinking of fuel.

 

On a plus side though, The bodies sound amazing

[tomcolinjones 26]

I just fitted my Jenvey bodies and Lumenition ecu (Cheers Baz)

 

This was originally mapped on yellow MI 16 injectors but when I fitted them I used green GTI6 injectors.

 

Would this cause overfuelling on idle ? My AFR gauge is reading 10 constant on tick over and car is stinking of fuel.

 

On a plus side though, The bodies sound amazing

 

 

what spec is the engine? 1.9 gti / mi16 yellow injectors are supposed to be good enough on standard engines. you will need a re-map to use gti6 injectors.

[welshpug 1,657]

you need to get it mapped again or re-fit those MI16 injectors, there's a massive difference in flow.

 

MI16 is 196 or 214cc/min @ 3 bar,

 

gti6 are rated at 264cc/min @ 3 bar though outperform this figure.

[Ryan 99]

If it was mapped with one set of injectors and you fit bigger ones then yes, it will overfuel.

[unariciflocos 49 1 Cars]

That will cause overfueling all over the rev range, not only on idle. ECU is keeping the injectors open the same time as it would the Mi16 ones and given that they flow more cc/minute they're letting more fuel in.

[Anthony 1,003]

The ECU has no form of feedback, and all it knows is that for a given engine speed and throttle position, that it needs to open the injectors for x milliseconds.

 

An Mi16 injector will deliver a given amount of fuel when it is open for the x seconds commanded by the ECU, whereas a GTi-6 injector will deliver atleast 23% more fuel for the same opening time, hence an over-rich mixture.

 

I don't know if Luminition has an injector scaling facility (I guess not) but you can probably get it back about right by reducing all the values in the fuel map by approximately 20% and then tweaking using feedback from the wideband.

[craig_007 1]

Thanks for the input guys,

 

I do fully intened to go for a remap when I get everything tidied up.

 

I was just curious if the 6 injectors would cause that much of a difference but when I see the flow rates that WP has put up it does make sense.

 

I might try the original yellow injectors and see what like

 

The engine spec is

 

Standard bottom slighty raised compression (10.8-1)

Standard head

Peter T stage 2 inlet piper BP270 exhaust

4-2-1 manifold

Jenvey Bodies

[Baz 421]

No worries Craig, good work getting them all fitted!

 

I'm pretty sure the software features injector upscaling that you could use initially as Anthony says, but also as said it really needs to be re-mapped or at least checked with a gas analyser throughout the rev range to check you're not doing any damage! Lean - det, melting pistons etc, or rich - borewash etc.

[pugpete1108 62 1 Cars]

as baz/ant mentioned, surely the software would have a req fuel caculator for bigger cc injectors?

 

this would lower the overal fuel for the entire map using certain parameters.