Mi16 Carb Conversion

[bazil_205gti 22]

Hi there

 

i currently have a phase one 205 gti i have put in a mi16 engine and am running it with all the mi16 standard ignition loom and ecu, i am looking at fitting carbs, can i run the carbs using the same loom to run the ignition module for spark, or will i have to fit a dizzy adaptor and use a 205 dizzy? and do away with the mi16 loom and ecu altogether. The sensor loom is not a problem as is totally seperate.

 

matt

[gazzer 1]

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[Baz 421]

look on main web page under articles

 

Although still relevant and will work, it's somewhat out-dated and there's much better ways to do it.

 

I'd retain the Mi management, leaving the injection side of things unplugged. Either link up the TPS to work with the carbs providing a better ignition curve, or as a simple/quick fix just stick it open.

 

Maybe not ideal but my old 309 was like this and worked very well, never got round to sorting the TPS properly! I'd much sooner do this than go back to rubbish old limited 8v management.

Edited May 9, 2010 by Baz

[boldy205 75]

Megajolt!! leaves you in total control to make it work properly

[rodionski 3 1 Cars]

Although still relevant and will work, it's somewhat out-dated and there's much better ways to do it.

 

I'd retain the Mi management, leaving the injection side of things unplugged. Either link up the TPS to work with the carbs providing a better ignition curve, or as a simple/quick fix just stick it open.

 

Maybe not ideal but my old 309 was like this and worked very well, never got round to sorting the TPS properly! I'd much sooner do this than go back to rubbish old limited 8v management.

 

Baz, could you please describe this in more detail?

 

I am about to convert to 45mm DCOE and your story is extremely interesting, but hard to believe.

 

My questions to this end would be:

 

1. How is it that using carbs the ECU would not cut the ignition and fuel since the AFM would be unplugged and thrown out of the car?

2. Did you simply throw away the stock fuel pump and replace it with the carb pump? Did you have to rewire it using the stock feed from the relay box?

3. Did you use stock camshafts? (I am assuming that you did, since I imagine that using something like fast street carbs would require a remapped ignition?)

4. Did you check the fuel/air mixture and/or ignition after such a setup with a lambda sensor? I fear that I could fry the engine without knowing as I have the non-cat no lambda version - D6C.

 

I would really appreciate your detailed comments to each of my questions above.

 

Thanks in advance!

 

rodion.

[rodionski 3 1 Cars]

Reaaallly need answers to my questions if you please....

[Baz 421]

It doesn't need the AFM, i guess it essentially uses the ignition map in 2d as it would no longer have the ability to tell the load it was under via the AFM flap or TPS, not ideal but better than totally unsuitable 8v crap.

 

Yes, on this particular car it had just a pick up in place of the OE fuel pump, and a facet pump instead.

 

Stock camshafts yes, but why would it need a re-map, you can use mildly uprated cams with standard management so this'd be no different.

 

AFR was checked with a High speed lambda as it happens yes, and i never heard any pinking/det and it went very well!

[rodionski 3 1 Cars]

Thanks for this! Really helpful.

 

I will be attempting to hook up some sort of throttle sensor on the carbs to help ignition though.

 

Did the ECU not try to stall the car since there would be no info from the AFM? That's what happens if you disconnect the AFM plug anyway..

I just know that in stalling the ECU will cut fuel AND ignition.

[unariciflocos 49 1 Cars]

AFAIK the Mi16 TPS is just on/off, so it only detects full throttle.

[welshpug 1,662]

AFAIK the Mi16 TPS is just on/off, so it only detects full throttle.

 

it has two switches, one for idle/throttle closed as well as one for WOT>

[rodionski 3 1 Cars]

No it isn't. It has three positions (i think there're two senders). Idle - Partial throttle - Full throttle. Could be heard when moving throttle bodies by hand on a stopped engine.

Edited May 27, 2010 by rodionski