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Please excuse the newbie question. I have a buick 3.8 with sc14 fitted. I have some standard l67 injectors and all my hoses and pumps are e85 compatible. Would the l67 injectors be enough to feed it e85. Also which areas in the tune should I be paying attention to to get the most out of it?

Thanks

You need about 1.5 times the fuel when running e85, so have a look at your current injector duty cycle in a log. If its always under 60% you can prob just get away with it.

Okay, so I am starting to get my head around this. I actually have bosch part number 0280155811's which according to the inter web are 42 lb injectors?

So I use the injector size calculator to work out the flow rate number? Then work the ve tables back once running e85?

Are the stock injectors on a buick 19lb?

stock injectors are 19lb yes, I reckon your going to need more like 60lb injectors for E85.

I'm only making around 3-4 psi with the supercharger. Am I correct in thinking that a 42 lb injector can deliver double the amount of fuel in the same time as a 21lb injector?

Do I need more than double the flow rate for e85?

Sorry if these are stupid questions. Just trying to understand.

well I guess it depends on a few things:

1. how close to the limit is the L67 injector in factory trim.
2. if you need a 19lb injector for N/A then you can fairly safely say you can get about 15psi boost from the L67 injectors.
3. e85 needing 1.5 times more than petrol means you need 60 LB injector to make 15psi on E85

so assuming all the above is right (and there is a lot of variables .... you may just get away with it on the 42lb's but I reckon it will be only just.

is the car currently running the blower on petrol ? if so like VL400 says, get a log of injector duty cycle at full noise and see where your at, whatever that figure is will give you the answer.

Thanks, it is starting to become clearer, your explanation make perfect sense. Yes the blower currently runs on the engine on 98 octane. I fear that I might be seeing some knock retard at higher rpm. Unfortunately, car is not registered and I can only test things out at the track. I am building an l67 for it, but that will take time due to budgetry constraints. But I do have the injectors and would like to get the buick running right, just so I can button it away before moving on. Thinking of it as a good opportunity to learn too without huge cost if I screw it up.

One more dumb question... Where do I find the VE Table calculator spreadsheet?

You can use 12P and the current ADX files with CalcVE to tune with now.

Post your bin and can bench test it at 5psi to give you a rough idea of injector DC with your current tune. Wont allow for boost dropping off at high RPMs or if your AFRs are miles off.

I'm just using the one that I downloaded from here when I did the NVRAM upgrade to my pcm. Have beat up on the car a bit at the track with it with no issues so far except a funny thing with the idle. Once it's warmed up, if you give it a blip on the throttle (idle id 700rpm) it will idle at 1150-1250rpm for a few seconds and the drop back down 700rpm over the next few seconds. Other than that it runs good.

What is calcVE and where do I get it? I did a search and it only turned your post ^up there^

Thanks