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Hi,
I just sent an email off to efi hardware about some 95lb injectors for my 383 vp turbo project.

He sent an email back recommending I use a sequential injection setup to change the injectors from firing once per crank rev to sequential so it fires only once per 2 crank revs/or once per cam rev.

I already have the the navram/comms/tunerpro and ose12p what is he talking about and can i do it with the setup i have now.
Why would he say that? do i need to chuck all this away and get something else?
Thanks.

The fuel controller ic in the 808 is not sequential capable. However sequential is overrated. It makes hardly any difference to power, and to get any advantage at all you need to make sure the injectors fire through an open valve, which is very difficult to do in the backyard and also limits the time the injector can be open to significantly below what you could otherwise. All fuel and air ends up in the cylinder with mpi or sequential.

The delco can single or double fire per rotation, and you can set the smallest pulse width for double fire before it auto drops back to single fire (half as many cycles with double the fuel each for the same requirements).. this helps with small fuel delivery with large injectors. This happens by default and is customisable. IMHO the 808 and 12p is pleanty capable of what you need, but I have not used injectors that large, would be interested to hear if others think 95lbers will be ok.

The reason for the 95lbs injectors is because I want to run ethanol fuel, 96% ethanol/4% water. I'm only guessing the size i need, If someone recommends smaller by all means tell me what you think.

I was working on around 700hp and 30%more ethanol approx than unleaded. engine is still being built so hp is unknown but it's a holden vp 383 stroker with To4b-2 800hp capable turbo.

Thanks.

Just watch out for high and low impedance injectors. The 808 is only high impedance capable. Lots of large injectors are low impedance and are driven using a peak-and-hold driver.

Yes, I'm looking at some bosch ev14 95lbers and are high impendance. I'm just not sure he strongly recomended the single fire per cam revolution as per the sequential. maybe it works better than 2 shorter pulses for the larger injector. not sure but I want to stick with the navram and see how it goes.

i wouldn't worry about the sequential recommendation ... just get the 95 lb high impedence injectors and you'll be fine

yeah him above me runs some big ones 80Lb no worries i run 60's on 3 cars no worries at all and i run them single fire at low pulsewidths to make them idle nice

V8hilux wrote:I'm just not sure he strongly recomended the single fire per cam revolution as per the sequential. maybe it works better than 2 shorter pulses for the larger injector.

As antus mentioned, the 808 does this (single and double fire) automatically. Just need to setup the min and max pulse width to enable it switching over to single fire mode.

V8hilux wrote:The reason for the 95lbs injectors is because I want to run ethanol fuel, 96% ethanol/4% water. I'm only guessing the size i need, If someone recommends smaller by all means tell me what you think.

I was working on around 700hp and 30%more ethanol approx than unleaded. engine is still being built so hp is unknown but it's a holden vp 383 stroker with To4b-2 800hp capable turbo.

Thanks.

all ethanol no petrol? over here i know a few people using E85, (15% petrol), i've never seen anyone run straight ethanol, but you certainly need massive injectors, so i think your on the right track with 95lb's, one guy i know is maxing out his 850cc's on a 4 cylinder pulling 320kw on E85, so most of us looking towards running e85 are going with 1000cc (95lb) you can probally get away with slightly smaller but why risk it?