luxembourgrst

hy well at first her is my configuration after a engine rebuild:

piper cam 285
mongoose exhaust
bailey dump valve
bailey oil breather
new stage 2 t3 turbo

7200 rpm rev limit (black box)
turbosystem ecu chip (appartly a no limit)

i set my boost on 1.4-1.5 BAR 20-21 PSI

i put my AFR on idle 14.7 and when i drive the car my afr is at 11.11 also on boost (after setting the black fuel pressure box on the meetering unit )
the car runs fine

but i have a BUG or like little missfire when i am in the 3 gear puch full throttle and at 4000 rpm it sound likee BRRRRRRRRRRR i hear the sound in the end exhaust pipe and the boost drop
only when i throttle very slowly it looks fine
...

can it be that my ignition timming is not good need to put it 12 degree before pmh no?

i also saw that my 2 green O-rings seal on the pressure black box on the meeering unit are done because i have a little fuel leak on it need to replace this 2 o rings

thank you

delbee1

What intercooler do you have??

Try running no more that 18psi, maybe your injectors are running lean, I cant remember how much boost you can run before needing a 5th injector, are you still MFI??

luxembourgrst

big airtec intercooler yes still MFI but i set up the fuel pressure to have a good AFR velue on boost

richardford

Well thanks to all for sharing it.

Karlos G

iTrader: (4)

It could be detonation, but I've no had the boost drop before.
Set your timing to 8 degree's BTDC and see what happens.
What actuator do you have, it could be creeping open, perhaps try a little more preload.

Fuelling is a little rich but wouldn't cause this issue.

luxembourgrst

i have a -31 acutator the turbo is brand new ..

the turbo is starting to load at 2700 rpm...


when i set the timing i let the car on idle an then disconnect the vacumm hoose to the ecu i don t need to close this vacumm line because i gonna do a air leak no? and then set it to 8 degree ?

Karlos G

iTrader: (4)

Yes close the vacuum line.

luxembourgrst

ok i will try thanks and only one questin why not 12 degree like standard setup?

Karlos G

iTrader: (4)

Because you may be experiences detonation and so by pulling the base timing back 4 degree's you'll see if it cures it or not.

luxembourgrst

ok well i put iit like 8 degrees an is fine no any boost bug at 4000rpm

but i also put my fuel pressure back because i had to mutch pressure that at the black box on the meetering unit i had a fuel leak
now it s ok no any more leaking

but now i have only 12.3-12.4 on AFR when i drive it also on boost it s 12.3 some times it hit the 11.00

before i always had 10.5 -11.11

is it enough safly with 1.4 bar turbo boost ?

Karlos G

iTrader: (4)

If it were EFI and you had some form of detonation monitoring then yes, but on ropey old MFI that's a little lean and your taking a risk IMO.

rsmark86

iTrader: (3)

In a nut shell no, it's why I hate mfi so much, it gets to a point when trying to get to much power that you end up running it abit rich low down to make it safe on boost


It was a good idea when the car was new but now it's just crap, aftermarket management is the best mod on a escort even at lower power levels

luxembourgrst

hmm well i gonna make it a little bit more pressure on the black box i know mfi is old i start to hate it lol

Rob_DOHC

iTrader: (4)

Whats spark plugs are you using and whats the plug gap?

Rob,

luxembourgrst

ngk bcr8es is 12.3 on afr with 20 psi realy to lean rob ?

Rob_DOHC

iTrader: (4)

Yes, should be closer to 11. Below 11.5.

Karlos's suggestion was a very sensible one. Retard the timing to see if that helps. However this will also reduce cylinder pressure which may hide a spark plug related issues. What is your plug gap?

When the noise happens does the engine misfire violently? If not then I suspect you are hearing detonation. For you to hear it at all with no det cans means its fairly severe.

Lean plus possibly too much advance is a recipe for detonation. Buy some det cans!



Rob,

luxembourgrst

yes ok the gap is like standard 0.7mm i didn t toutch them


before a had 11 11.5 on afr but my timingwas not set can t remeber where it was

then i took the fuel pressure down to 12.3 on afr because the black pressure box on the meetering was leaking fuel with 11.5 afr i also change the 2 gasket rings
and i set my timing on 8 degree and no any problem the car runs fine know but 12.3 AFR is not savely need to put it back to 11 -11.5 because im at 20 psi

before i realy hear noise at 4000rpm in the end on the exhaust when it was boosting.... and the engine bugs dreeeeeeeee but i think when i push the throttle gaz slowly it was fine .

but i really think it was the timing setup because the car drive very more fine know and better but it s also because is leaner lean-more perfomence but not savely..

well whats about the gap is this important?

luxembourgrst

well i put it back to 11 - 11.8 when im on throttle but still the problem if im at 2000 rpm at 4 gear and low speed and push the gaz pedale full down its lean like 18 on afr and than slowly goes to 14 .13.12.. on boost

and also if i direct push the gaz pedal down i have some misfire at high rpm

i always to push slowly down the pedal too have a goood result

and i have again a little fuel leak at the black box on the meetering unit when i puch it back to 11-11.5 on AFR before i had 12.3 AFR and no leak

what i don t understand is do i every time need 11-11.5 AFR on driving normal ( it s ok ) but when it boost i think is impossible to have 11.5 it every time stall a little bit to 12.5 -13.5 AFR when the car is boosting like full throttle on 1 gear...?

i know is the old ke jetronic

Rob_DOHC

iTrader: (4)

To be totally honest with you it sounds like you should be looking at efi. Your MFI seems to have caused you so many problems

Rogeyboy

iTrader: (2)

I'd be doing one of 2 things...
Taking it to a pro to get it set-up so you know its safe as you are going to kill something in your engine soon

or

Swap it to efi and fine tune it all yourself with a standalone ecu, like ofam

mgtkr1

turn the boost down till you can have it setup right and drive it off boost until you know its set up safely. I bring the boost back to 1 bar and see what its like. id still refrain from driving hard/on boost tho until your 100% it fuelling right

luxembourgrst

yes i know but to turn to efi it s a lot of job also to find all the parts who i need burton need to do a efi kit or something


well i gonne drop my boost..

mgtkr1

inbox karlog g about aftermarket efi...

luxembourgrst

well i go take my turbo pressure from 20 to 18 psi at will look to do set up again my fuel to 11-11.5 on AFR
but whats again with the spark plug gap? i have the NGK bcr9es it think the gap is 0.7mm no ?

Red_bull

I have a simular problem on mine with the strange sound comming of the engine. Only happing when you hit the pedal completly. I have it in different gears, but it always starts after a gear change when i hit the pedal.

When i keep my foot down the sound stays, rpm stay exact the same. When take foot up and down sometimes it goes again sometimes i need to hit it slower and it goes.

Does this match your problem? or your is different

CF20

sounds like det to me mate

Red_bull

Isn't there a bigger chance its retarding for some stupid reason?

Anyway i need a recalibration anyway so it might dissapear then

luxembourgrst

yes it was the ignition had it before at 12 degree and now at 8 and it s still better

but my ke jetronic is strange i have know a AFR 11.7 but when it boosting it goes up to 12.7 impossible to stay at 11.7 also if i am in the 5 gear at only 50kmh and i push the gaz pedal directly down it hit s the 18 on afr what is normal but teh goes back to 12.3 AFR when the engine goes up in rpm

but also at idle the afr goes from 13.9 -14.2 to 14.7 i but the idle is stable

ke jetonic is not the best but is ok i want to go back on a dyno to watch how mutch power i have ...

ROB7656

Timeing

Red_bull

Think your KE tronic is running on its max. I ran 210 bhp with 0.9 bar of boost. Isn't your situation maybe the max for MFI?

luxembourgrst

yes it s maybe the max