believe you need 80's to run E85.

 

Lol depends on pulley . I've been able to pull 92% idc with a 2.8 on a ported blower and 60s anything below that run 80s

 

So you can run E85 on 60s? But why wont ZZP tune unless you get their 80s?

 

U DON'T NEED 80S TO RUN ETHANOL.. lol..... Pulley.... Matters..

 

Because its a canned tune. There canned tune will end up running way to rich and it'll max out the 60s..... I run a 11.5 and ramp it up top to a 12.3-12.5 and it works great. Btw the afr is ethanol converted to gasoline stioch lol.

 

really you dont want to run injectors for any amount of time passed 80% idc. going through a couple gears on the street, even drag racing, its alright to run them higher, however say you were road racing, you wouldnt want to be above 90% idc. injectors get hot and can stick open. when calculating how big an injector you need for a given application, 80% should be the max to plan for.

calculating injector size is fairly simple using an online calculator, however with the lsj its a little more complex. the fixed pressure fuel system adds another variable. vehicles with a return fuel system and a rising rate regulator raise fuel pressure when in boost (generally 1:1, meaning for every lb boost you get 1 lb fuel pressure), and drop 1psi for every 1psi negative pressure, or vacuum (1psi fuel pressure decrease for roughly 2 in/hg vacuum). this fuel pressure change will offset the pressure in the intake manifold so the injector working pressure is always the same, in many cases, 43.5psi, or in newer stuff, 58psi. now, the lsj doesnt use that system, as i mentioned its fixed pressure. so really under 15in/hg manifold vacuum the injectors are more like they are at 65.5psi, making them act larger than they really are. now under boost, lets say 20psi (i know a lot for an m62), the injectors have 20psi working against them making them have a true running pressure of 38psi. this has to be figured in when calculating injector size as you will end up with too small an injector if you dont. this is also the reason the lsj needs larger injectors as compared to some other 4 cylinders with similar power levels.

now, zzp has done their homework, i calculate that outputting 285hp (roughly 250 wheel hp) at the flywheel you would require 50lb injectors and would have to run them at 90% idc. granted thats at peak power and isnt going to be up there for long. now, this is just fine, works fine as long as you stop mods at a 2.8" pulley. however 99% of us end up wanting more and 50lb injectors could be a poor choice. pushing the m62 to its full limits some have achived 300whp, and that in theory will push 60lb injectors to 85% idc, and 50lb injectors to around 105%.

 

So Sharkey, I would want to go with 80#, since I will be going with a 2.7" and I also have a E85 station near me, how does the E85 out power pump gas?

 

Higher octane.

You can run more timing with less chances of knock.

 

So what kind of psi would I be seeing with a 2.7"? So E85 allows more advance timing

 

Yes, E85 will allow more timing advance.

I can't tell you how much psi you will be seeing.

Psi is determined through a number of factors.

I could have the same exact setup as you, but could make less or more psi due to temp, climate, elevation, etc. I could also make less psi than you, but be making more power.

There are psi ranges for given pulley sizes on this site, but take them with a grain of salt.

 

Does exhaust backpressure value into it too? Because I know it does on turbo cars right?

 

Yes, exhaust "back pressure" affects boost levels.

A free flowing exhaust will yield lower boost, but generally more power.

Although, supercharged cars are not as sensitive to exhaust back pressure as turbocharged cars.

 

So what kind of KR will a full 3in exhaust yeild

 

so if i running a 2.9 or 2.8 pulley what injector size i need??

 

If ur running a 2.9 you can put in the 50#'s. Me and James(Chevycobaltss3) tested the 50#'s in my car with 2.9 and they were fine. But if your going to go 2.8 eventually or even lower then just spend the money and get 60#'s or 80#'s

 

i will have more hp with the 60s ?? or it will be the same of 50?? #50 are less expensive in gaz than #60?? what is the difference between these injector??

 

i ordered #50's for my build with a 3.0 pulley and meth and all the supporting cooling mods from zzp. i went with 50's so i dont have idle issues and im not planning on going to a smaller pulley.

 

In the last year i went from 42's to 60's and now to 80's and them most likely next year to 1000's. I could have samed myself a good amount of money buy just getting the 80;'s first when i first started to upgrade.

 

For nearly every M62 build, 50's are the way to go. Less cost, no idle issues, larger than what the M62 can max, no need for an injector harness, easier ECU programming, easier install.

I don't really see a point for 60's. If you need more than 50's you may as well get 80's. If you are running E85, then you probably run a small pulley and 80's are the way to go. E85 requires 30% more fuel. A 60# injector becomes a 42 and an 80 becomes a 56 on E85.