please post duty cycles

[royston1xx]

Hello,can anyone with these mods or similar who are using 550primary and 1200 secondary injectors tell me what there duty cycle is at 1kg/cm on stockport engine- mods are intake,frount mount,dp,mp,blitz catback,apexi pfc and bnr33 fuel pump at 38psi base fuel pressure.My car keeps choking after 5500 rpm and my duty hits 92% at 7500rpm,Thanks Roy.

[maximtaylor]

Roy

Mine was running 90% duty at one bar with the STOCK injectors, at 7500 revs, but never choked or hesitated, unless I had less than 1/4 of a tank of fuel.

With the 1300\'s secondaries I am running about 75% duty cycle, albeit with a bosch (big boy!) 044 pump.

If you are running that high a duty cycle with the 1200\'s, you must be injecting a f@@k load of fuel in! Far more than you will ever need on an unported engine!

I assume that you changed your ecu injector settings correctly to 1200\'s secondaries via commander or datalogit (sounds stupid, but it has happened...)

Are you on a stock map?

Please describe \'chocking\' further, its just that there are quite a few possibles!

My best guess is that you are running so rich, that this is causing the engine to sound a bit like you have a dodgy plug or similar right at the top end of a hard pull.

Carl Hayward will no doubt recall a recent visit we made to a rolling road where this over rich state caused similar problems.

Regards

Max

[royston1xx]

Geff set the fueling  to run 11-1 up to 6k rpm and 10.5-1 after which was fine,but recently it is stumbling and you can feel it  sort of choking up but not all of the time,sometimes it is hardly noticeable and others it doesn\'t want to rev properly.Its not on the stock map geff set the fuel and i increased the split a little.I put 1200 in the injector setting on the pfc (haven\'t got datalogit) and +.04 ms.Thanks for the help.

[DRAGON]

Roy, I think your map is way to rich, there is no way you should be hitting 92% inj duty with those injectors and stock engine and turbos.
If you are gettting 92% inj duty with 1200 secondaries you should be putting down about 430 @ the flywheel.
Get a wide band on the car and someone who knows what a/f ratios to aim for.
Another thing is that problem does look very much like the 1200s have been put in but the power fc does no it, therefor you would be hitting 92% cus the ecu thinks you have 850s, Just check the injector settings again to be sure.