Trying to run S40 on twin injectors

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Andrew
Posts: 5
Joined: Fri Jun 30, 2017 3:01 pm
ECU Model: S40 Pro
Firmware Version: 81.02

Trying to run S40 on twin injectors

Post by Andrew »

Hi, I have a strange issue at first I thought I was missing something simple and I have been through the manual but basically I am trying to run twin injectors on a peugeot 205 TU3 engine on GSXR throttle bodies, when I turn on the twin injectors the revs increase even on the blend map with all the sites zeroed out, I spoke to Alex at DTA and he give me another map to try that he had done a simulation on a so new was working fine but I have loaded it in and corrected the fuel as it needed more but it's still the same as the map I had in as in doing the same thing. The Idle valve is defiantly turned off I have even zeroed all that to check but tonight on further investigation I have noticed that it is running all the injectors when the twin injectors is not ticked but when I tick it, it turns the second set off.
Has anyone come across this before?
I doses seem to be giving more fuel to the first set of injectors but could I know they are there with out it been told?
I am getting it mapped tomorrow but really I need this sorted as don't want to pay for roller down time if it was just running ruff fine but something is not right could is even be a software issue?
Thanks andrew
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ignitionautosport
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Re: Trying to run S40 on twin injectors

Post by ignitionautosport »

With twin off it uses all injector drivers as normal injector drivers. So that sounds correct to me.
The revs increasing when you turned it on could be the fact that it was running really rich before, and leaning it lean out let the engine rpm rise as it's happier.
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Andrew
Posts: 5
Joined: Fri Jun 30, 2017 3:01 pm
ECU Model: S40 Pro
Firmware Version: 81.02

Re: Trying to run S40 on twin injectors

Post by Andrew »

Ok thank you, yes with them turned off it seems to sit at 0.95 and with them turned on 1.00 my second set is only 10cc bigger but further away from the inlet valve,
So would you say is was doing semi sequential on each cylinder then? Will it automatically do that if it's connected and the twin injector is not selected and the idle is turned off as would semi sequential normally be wired in that way?
Thanks andrew
Alex DTA
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Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
Distributor: DTA
Firmware Version: 79

Re: Trying to run S40 on twin injectors

Post by Alex DTA »

I seem to have misunderstood somewhere along the line. I thought you said both injectors were running when you turned on twin injectors.

On the map I sent you, with twin injectors unticked, the ECU will use both outputs, as it's set up to run in semi-sequential injection.
With twin injectors ticked, only the first set should turn on until they are at max duty cycle, then the rest should go to the second set.
To test this with the engine running, just unplug the second set of injectors, and nothing should change.

It sounds like it's all working correctly.
Andrew
Posts: 5
Joined: Fri Jun 30, 2017 3:01 pm
ECU Model: S40 Pro
Firmware Version: 81.02

Re: Trying to run S40 on twin injectors

Post by Andrew »

Well it's now half mapped as we ran out of time so only got the one set of injectors mapped up although we did do a nearly complete map on it doing the semi sequential firing thing interestingly both so far have give the same power results and the same as a carb and dizzy but are less drivable due to my throttle bodie choice i.e. To big way to big and I seem to have a wiring issue were the ECU keeps loosing power on crank I have fed it from a few ignition feeds off the car now and it's still the same so I have that to look at so as a temp it's on to the back of the kill switch via a toggle switch. At the minute I feel like I should have just left it on carbs and dizzy I have been told I won't make any more power than I was so it's looking like it was a wasted exercise any way..
Last edited by Andrew on Sun Jul 02, 2017 3:29 am, edited 1 time in total.
stevieturbo
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Re: Trying to run S40 on twin injectors

Post by stevieturbo »

S40 cannot do sequential ?
Rob Stevens
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ECU Model: S100 Pro
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Re: Trying to run S40 on twin injectors

Post by Rob Stevens »

It does semi sequential where by the second injector drive fires 180 deg after the first.
Also curious how you are chopping and changing the wiring from twin injector to single semi sequential. I think I'm right in saying that driver 1 should do cylinder 1+4, driver 2 cylinder 2+3
lumley32
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Joined: Mon May 10, 2010 5:09 pm
ECU Model: S80 Pro
Firmware Version: 61

Re: Trying to run S40 on twin injectors

Post by lumley32 »

correct me if I'm wrong but an s40 has 2 injector outputs? so it can run semi-sequential or twin injector, not both!

what made you think it would make more power? a well set up set of carbs are just as good as EFI on wide open throttle......
Alex DTA
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Joined: Fri Feb 28, 2014 1:03 pm
ECU Model: S40 Pro
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Re: Trying to run S40 on twin injectors

Post by Alex DTA »

lumley32 wrote:correct me if I'm wrong but an s40 has 2 injector outputs? so it can run semi-sequential or twin injector, not both! .
Correct. But if you have 8 injectors fitted, the settings need to be correct.
So if you tick twin injectors, only those on output 1 will work at idle.
However, if you untick that, all 8 will fire, as the ECU will use both the outputs.
Andrew
Posts: 5
Joined: Fri Jun 30, 2017 3:01 pm
ECU Model: S40 Pro
Firmware Version: 81.02

Re: Trying to run S40 on twin injectors

Post by Andrew »

It did make 3bhp more peak.. and took a bit of a flat spot out in the end with the dizzy it would have self distrusted it's self to get that setting for the top end and rolling roads just don't recurve dizzy any more. Maybe I wasn't clear but it's mid range power I want and snap WOT things carbs just can't do as well no matter how well set up they are the main issues is on the 205 is the inlet tract in carbs is a bit to short and the only real way to get a correct length is EFI..
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