Fuel Mulitplier in Crome questions????
 

One of the basemaps i recieved from Xenocron got me started and is running pretty good in Vac and light boost, so i am tuning it and i noticed that in the fuel mulitplier the new injector size is 353cc and i have 450 cc injectors. Do i need to leave it at 353 and tune it or change it to 450 and tune it?? I read somewhere on pgmfi that the fuel multiplier is not totally correct. What do you suggest??

THanks!

Re: Fuel Mulitplier in Crome questions????
 

leave it where it is and tune the tables....

that is probably an old skool bin...before Fuel Tools.

The Fuel Tools functionality has been improved since then...

Re: Fuel Mulitplier in Crome questions????
 

Yea, I notice that on a lot of the maps I get from the crome bin directory, the injectors are either stock, or some weird number. But the notes in the directory say otherwise.

Re: Fuel Mulitplier in Crome questions????
 

What about current versions of Crome? Is it safe/ok to rescale the injectors to thier actual values, or do they still require fiddling with??

Re: Fuel Mulitplier in Crome questions????
 

Okay, sounds like a plan :1. But can someone answer the other dudes question

Re: Fuel Mulitplier in Crome questions????
 

It's actually a good thing to "under scale" your injectors, it helps with tuning your idle and such when compared to injector latency times for large injectors. It also tends to give you room up top when you start getting close to the "99%" duty cycle time. Do what Chris says and leave it where it's at.

Re: Fuel Mulitplier in Crome questions????
 

i guess i'm confused here a bit. you underscale it so you run the wrong injector latency times? can you elaborate a bit more

thanks

-Luke

Re: Fuel Mulitplier in Crome questions????
 

I don't understand either. Latency is a due to the injector being physically larger.

Re: Fuel Mulitplier in Crome questions????
 

I can buy that if you've got an old version of software that doesn't support fuel tools, but I think (as well as read) that it is paramount that you input the proper static injector fuel flow rating and tune injector battery offsets properly in order to maintain consistent AFR's in a multitude of atmospheric conditions. Improper injector dead times will make tuning a real hell.

Re: Fuel Mulitplier in Crome questions????
 

Something else I noticed today while tuning.

I started with a p72 rom, scaled for 450cc injectors yada yada added all the necessary plug ins.

Now, the only thing different I did this time that I've never done before is change the engine capacity in the fuel multiplier. I used 2156 since I'm tuning an f22.

Instead of scaling by .533 it did .7xx or something like that.

it actually was a better basemap than any other basemap I've made for f22's.

Anyways, when I reopened the bin I noticed that under new injectors, there were 333cc injectors, not 450's.

I didn't mess with it because the car runs perfect. But I was just wondering why it does that.