Running lean
Turbo Mini Forums

hi all, my mot is tomorow dinner time, ive just had a first little drive in the mini but im worried because at certain RPMs it runs lean so i quickly put it back in the garage. Ive checked it on the colourtune and the lambda guage.

Im using a bog standard metro turbo carb and needle. Pot_dans bringing over a AAA needle tonite to try, is it ok to drive to the MOT on one of these? I think it will make it really rich so better until tuneup?

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

hey up feebs, i think the A prefix needles are for the smaller hs4/2 carbs mate although im sure someone can say for sure. i know my turbo carb runs a pretty rich B needle to keep it rich untill it gets in for a RR but i cant remember what it is off top of my head. will have a gander at it tonight if i get a chance.
steve

doh! why did i start messing with it!

oh ok!!

Im actually supprised because i thought that using a standard metro turbo needle would be too rich for a 998 turbo, because of the smaller engine. Can anyone explain why it isnt?

Also, has anyone ever found colourtunes any good? It seems such a rough way of tuning, the colour never stays constant it flickers yellow blue yellow blue all the time, and ive never seen a white (lean) on it on idle or a constant bunson blue, even when the lambda is telling me its lean at idle.

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

To tune my mixture also, through the mixture screw, between fully screwed out and fully screwed in there is a peak where the revs rise. Is this the rough area where the optimum mixture is?

When you get to that bit, and you get a yellow flame for the colourtune, do you screw outwards or inwards to get the "bunson blue". Either way i turn it does get a little bluer, but still orange flicker.

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

Colour tunes are pretty rubbish as you can't check the mixture at any load, really only any good for checking idle m,ixture.

The mixture screw shoud be used for setting the idle mixture, then left alone. A file should then be used to profile the needle where necessary (unlesss you have a stack of needles to choose from) but DON'T file the idle part of the needle.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

Poodle down the mot place with the choke half out

Metro turbo weekend driver,Mini turbo in the making again!

right! got it set really well now so its idling at 14.7 on the guage, when driving it runs a bit richer - goes to about 16 - 17.

however its really hard to set off, it really really struggles to get going, missing sometimes, its just really really slow and you cant press the throttle too much or it dies.

If you wait thought, slowly the revs rise, when it hits 3000 rpm its off!!! It sets off beautifully, lambda reading is good and no missfiring or anything , and when you change gear on boost it keeps going well, unless you go below 3000 rpm then it bogs down again.

Checked absolutely everything twice over, i can only think of it being a couple of things, the TT map im using not working on my car for setting off, or because my bleed valve (which is not adjusted to anything) is connected between the actuator and the plenum (because I have no outlet on my turbo) because of this i think that the bleed valve might be lowering the fuel pressure or something because the fuel regulator also sees this pressure? Is that possible?

Does anyone have their map i can use?

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

The only other thing i can think is maybe an inlet gasket is leaking? I was tihnking this because on my NA mini when the gasket leaked it reved up fine stationary and sounded ok, but wouldnt set off. On the NA mini you could hear the gasket leaking though, but theres turbo noises all over that place on this engine!

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

have you topped your dash pot up?

i just put 23 degrees in all the boxes when running in, just like having a fixed dizzy seemed ok, its now set up properly yho.

no longer a series, but still 1.3 turbo.

Does sound more like fuel than ignition. What is your fuel pressure like? you may have a slight flooding issue at tickover if it's a bit high, this will then take time to clear. Massive amounts of fuel can confuse the lambda sensor.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

AlexF

thankyou for the replies!!

Canceled the MOT and not driven it since. I dont know if the megajolt might have a problem though ive rewired the plug and everythings perfect, ive checked all the wiring and its all perfect. Im using the insulated wiring straight from the fiesta, but the RPM is always reading 467 in the megajolt software, and if you start the engine it crashes the software. Ive got another EDIS to try and another edis plug, and also im going to switch the wires round like hippyinamini suggested too even though ive checked it over and over now and it all seems right.

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

changing the base line fuel pressure doesnt effect the overall fueling by very much at all.

certainly I have tested 1 psi either way from a start point of 3.5 and recorded little difference.

Alex

AlexF

thanks alex!! one less thing to try

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3

or because my bleed valve (which is not adjusted to anything) is connected between the actuator and the plenum (because I have no outlet on my turbo) because of this i think that the bleed valve might be lowering the fuel pressure or something because the fuel regulator also sees this pressure? Is that possible?

Does anyone have their map i can use?[/quote]

feebes, id make sure your plenum to fuel pressure regulator is a dedicated feed ,with no t pieces or valve etc in it , you could take yuor boost pickup off the manifold instead .also have yuo disconnected the pipe that run round from the brass fitting just in front of the carb butterfly on the top of the carb ,and used to go round to the side connection for the mid range lean off function on the metro ?
also ,is it poss that yuor ecu is not getting a proper rpm signal ,and so sticking at 10 degrees until the 3000 rpm mark ,maybe the pickup is to far from the pulley?(this is probably impossible cos the ecu with no rpm would not make a spark would it ?) regards , robert.

Edited by robert on 2nd Jul, 2006.

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM