4xid1000 max e85 hp?
 

just decided to go e85 on my engine, but my injectors are only 4x id1000.... will they max out before my s4 stockblock w/ 3mm apex seals? i have an fuel lines and walbro 400 e85 pump and gtx35/40r turbo running haltech ps1k with aem smartcoils and raceplugs

you have 4000 CC/Min of Gross injector capacity at 3 Bar static pressure (43.5 psi)

there are two deducts to get to Net injector capacity...

duty cycle limit (85%)
lag (13%)

you have 2958 CC/Min of Net deliverability

2958 CC/Min is .78 gallons per minute

.78 GPM weighs 4.953 pounds talking gasoline

at 11.0 AFR that would combine w 54.48 pounds of air or 788 CFM

788 CFM is 410 rotary rwhp SAE

since E85 has 82,000 BTUs and gas has 116,000 BTUs per gallon E85 produces
70.6% of gasoline...

410 X .706 = 290 rw rotary hp SAE

howard

howard.... always thanks dude, big help here on the rx7forum

and gasoline this season it is....

your welcome...

i am really happy we have an alternate fuels section. it is no accident that the largest folder i have is entitled, "Fuel."

i plan to become more active in this section very shortly when i actually have data.

as soon as i get off the computer i am out doing some road tuning on pump and 25% water, 75% meth which i think may be the ultimate AI mix.

after getting tuned out on that mix i am doing a FFS and plan to run a 50 50 mix of pump and E85.

the nature of fuel going into our tiny high output motors may be the most important single item. depending on.... "what's in your motor?" you can be supersonic or picking up the pieces.

howard

i forgot to say thank you mr. Howard :-), its been a great help!!

290 hp no way

given my assumptions:

11 to 1 AFR
43.5 static fuel pressure....

WAY.

there is only so much power in fuel. E85 has 82,300 BTUs per gallon.

gasoline has 116,090 BTUs per gallon.

if you want to run a bit leaner and burn more air, say 12 to 1 you can make 316.

if you raise the rail pressure to 58 psi (4 bar) you can make 334 at 11 to one and 364 at 12 to one.

you raised fuel pressure 33.3% but flow only rises at the square root of the increase or 15%


all this is splitting hairs...

the OP has a turbo that can make over 70 pounds of air and fuel enough for 55 pounds per minute w E85.

add injectors or run gas or have your engine builder on speed dial.

howard

Howard is right at 43 psi 290hp is correct


Injector Dynamics - Horsepower Calculator

so 1200 cc injectors make on e85 ??

So to "K.I.S.S." the computations into something my simple mind can understand at 43.5 psi and a quick and dirty ballpark figure would be something like this?

11:1 afr = 72.5 hp per 1000 cc's of fuel (290 hp / 4)

12:1 afr = 79 hp per 1000 cc's of fuel (316 hp / 4)

So that would put the 850/1600cc combo I'm running capable of 355 at 11:1 afr, and 387 at 12:1 afr safely.

"So to "K.I.S.S." the computations into something my simple mind can understand at 43.5 psi and a quick and dirty ballpark figure would be something like this?

11:1 afr = 72.5 hp per 1000 cc's of fuel (290 hp / 4)

12:1 afr = 79 hp per 1000 cc's of fuel (316 hp / 4)

So that would put the 850/1600cc combo I'm running capable of 355 at 11:1 afr, and 387 at 12:1 afr safely"

sure, as long as the "fuel" is E85.

as far as "safely" ... i didn't see "safely" in my post. depending on a large number of other factors 12 to one can be safe or not... and of course you know that but it does need to be stated.


as to keeping it simple, i agree, simple should always be an option. i presented my calculations so others can understand the assumptions and methods... and then can do their own calcs.

Flaco, i diidn't respond to your post as i wasn't clear what you are asking. if the question is what would 4 1200 CC injectors make on E85 the answer would be 20% more than 4 1000 cc injectors as all the factors are linear.



howard

im not trying to get in an argument with you sir. but how the hell with 4 1200cc injectors i was able to do 475 whp on e85 ? car was at 16 to 18 psi. and afrs at 11.2-11.5 and i wasn't at 80% yet

if you wanna run E85, then get 4x2000id and -8 fuel lines with an A1000 pump

Im actually curious what size lines are for what kind of application, like higher hp cars need a certain size bigger/smaller or is it something else that goes into the descision?

a1000 pump ? nahh you crazy :lol:

You can regulate the amount of fuel into the engine with injector (duty cycle)... keeping a large volume of fuel on stand by with a huge pump and -8 line is a safe guard and will support a very lagege turbo later down the road.

Why run 2000cc ID and not have the appropriate line and pump?

290 seems a bit off to me as well..

just a guesstimate but i would say 4000cc's on most pump E85 is going to push well over 350whp, since ethanol content is rarely 85% and usually in the 65-70% range. i setup a customer's car with 8000cc's and 720lph of pump to do 700+whp but we will see, if he ever actually has the money to tune the thing or get over his fears. the injectors should easily do the job but the pump(s), filter, lines and return system are where most issues arise. even on pump, i find most pumps take a dump well below their rated output levels when in REAL WORLD situations. fuel heat saturation and increased resistance in wiring usually causes pumps to fall on their face when pushed to their limits.

problem is if you calculate E85 with the maximum ethanol content and rich 11.0:1 gasoline wideband AFRs you wind up with shitty figures which are unrealistic and just wasting fuel. (yes, 11:1 is rich with ethanol tuning)


we shouldn't be talking about things we know little about, it is wasting people's money needlessly. BUT i would recommend 2000 secondaries and leave the 1000 primaries alone. your walbro will also be stressing a bit to keep up with the demands of that 530-600whp turbo, you might consider a kenne belle boost a pump for the fuel or run a twin pump parallel setup. as you sit, you wouldn't be able to max out the airflow of either of those turbos with your fuel limitations. the stock fuel hardline also is going to be moaning about the volume of fuel, or rather the pump will be so, upgraded lines are pretty much going to be a necessity.

just finished my an -8 sized fuel system (2 paralell 1/2 inch stainless pipes all the way to enginebay then an-8 stainless shielded teflon hoses) and ordered id2000 for my secondary, and 2 bosch 044 pumps, the walbro 485 will hopefully keep up as a liftpump for the bosch pumps? huge ass stainless fuel filter ordered aswell. Lets crack some rear irons ye!

You should get bigger injectors to get more out of e85. You need much of it to make considerable power.

That 1000,2000 and pumps should get you better results.
Also read this, https://www.rx7club.com/alternative-...rience-952149/
One of the most informative threads on E here.

what base fuel pressure were you running on this setup?

Im going to run 4 2200cc injectors. What about me on E85??

this maybe old news, but back around 10yrs ago, i was at a track in s. fla.

some guy came up from PR, rx7 2rotor, had 12 fuel injectors, (looked like a porcupine) ,big lines, and 6 fuel pumps in the trunk! on methanol.

musta worked ran a hi-7second run , 10 yrs ago!

no doubt rotories love fuel!

question; has anyone stepped up to Nitromethane fuel yet?