E85 RB25DET

[racebreads13]

im planning to go to e85 on my rb25det and upgrade some other things as well heres the parts i have and the ones im planning on getting..

i want to go e85 be cause its wayyyy cheaper then race fuel and i cant find anything over 101 where i live besides e85 i also never drive it except to drift so ... also i read e85 burns cooler and s13+rb25+cooler=

have:
power fc
stock rb25det s2
walbro 255 fp
z32 mafs
straight piped 3.5" exhaust
freddy mani w/ q45 tb

parts im planning on getting/ have questions about:

700-1000cc injectors- what company sells good ones? these would be perfect for 350-450whp with e85 correct?

gtx3076r turbo have not heard anything about this turbo and rb's but looks perfect for my goals and seems like it spools fairly quick acorrding to the graph. if you know of a better subsitute lemme know(cheaper/spools quick/great quality) for drift so need the response

should i upgrade the fuel pump for the power goal im trying to get on e85? or will the walbro be fine?

apexi boost controller add on for pfc

is there any gaskets i should worry about?

should i do a cometic head gasket and arp studs/bolts?

fuel hose is there any certain type i should use??

maybe plastic fuel cell?? since e85 rusts gas tanks???

am i missing anything?

[racebreads13]

http://cgi.ebay.com/ebaymotors/6-JECS-1 ... arQ5fParts

found these what ya'll think

[chad b.]

#1 you don't need e-85 to make 450whp with an RB25DET. You can do that on pump gas.
#2 if you're goal is only 450whp, why even do an RB swap in the first place
#3 you need 20% more e85 than pump gas to make the same hp

[racebreads13]

1 yes i know

2 i want 450 reliably.. and i have done a sohc ka-t and currently have an sr vert and a dohc ka-t i love to diversify rb was a my dream when i was 16 and now im 20 n happy lol

3 well from what i been reading its 30% more and as the cost of e85 vs 91 gas (which is all i can get here) it will cost about the same but ill be running a 100-106 octane fuel sounds good to me

anyways thanks for the reply

[nelson8708]

i think you could hit 450whp on e85 with 555cc injectors if your setup is efficient (what turbo manifold? How efficient is the FMIC?) but, get the biggest injector you can control this way if you want more you have room to grow.

[chad b.]

Another thing to consider is running out of fuel per the pump. Most people run out of fuel in the 450hp area on e85 with a single walbro. Some have made a little more, but they're running 1000cc injectors and high base pressure. If you plan on running that Power FC, you need to find out how much injector that thing can handle. There isn't much of a price difference in 550's and 880's - 1000's. That being said, I would run the largest I possibly could with the FC so later on, if you want to make more power, you won't have to buy the same parts (injectors) twice.

[racebreads13]

i think you could hit 450whp on e85 with 555cc injectors if your setup is efficient (what turbo manifold? How efficient is the FMIC?) but, get the biggest injector you can control this way if you want more you have room to grow.

stock turbo manifold, the fmic the hot pipe is 2.5" from the turbo into 3" and the cold pipe is 3"
i made a 3" intake
and i made the exhaust which is 3"down pipe and the rest is 3.5" the whole exhaust will be 3.5 when i get the new turbo

heres some pics

[racebreads13]

Another thing to consider is running out of fuel per the pump. Most people run out of fuel in the 450hp area on e85 with a single walbro. Some have made a little more, but they're running 1000cc injectors and high base pressure. If you plan on running that Power FC, you need to find out how much injector that thing can handle. There isn't much of a price difference in 550's and 880's - 1000's. That being said, I would run the largest I possibly could with the FC so later on, if you want to make more power, you won't have to buy the same parts (injectors) twice.

yea i been thinking about going bigger then 1000s but not sure yet

i heard the walbro can support 500 buuuttttt ive been looking into getting a fuel pump from deatschwerks 400lph fuel pump

[J2fast]

for that size turbo you can make 450 with e85 with setup you posted. on my 1st rb25 i have a gt35r with 880 injectors one fuel pump with std upgrades and fpr set to 55psi as base and made 485 to the wheels. but you have to know someone who can really tune e85 cuz its not the same as gas an will not make power like gas. my last rb25 setup i went with twin fuel pumps an 1000cc injectors with a t72 turbo an that was only good to about 515 whp at 18psi. but i changed pumps an was able to go 22psi with alot more fuel and made 653 whp before she blew now im going built block. that will give you an idea what to expect from the fuel and power to made. its not all about the hp you get its more of the tq you gain from using it (IF TUNED RIGHT).

[nelson8708]

that stock turbo manifold is the choking point for your setup. I'd get some 750's or 880's and call it a day. The detchwerks pump is a 300lph pump, not 400lph. For the price its only competitor is the Bosch 040 or 044. IMO i'd go with the Bosch, it has metal gears while the detchwerks and walbro have ceramic. Under high pressure the Bosch will out flow the detchwerks from the graphs i've seen, however the detchwerks is the only one out of those three that is listed as e85 compatible even though the other two seem to do fine pumping e85 as well. 300lph pump should clear you till around 600whp

[racebreads13]

that stock turbo manifold is the choking point for your setup. I'd get some 750's or 880's and call it a day. The detchwerks pump is a 300lph pump, not 400lph. For the price its only competitor is the Bosch 040 or 044. IMO i'd go with the Bosch, it has metal gears while the detchwerks and walbro have ceramic. Under high pressure the Bosch will out flow the detchwerks from the graphs i've seen, however the detchwerks is the only one out of those three that is listed as e85 compatible even though the other two seem to do fine pumping e85 as well. 300lph pump should clear you till around 600whp

thanks for the advice and i must have read wrong when looking at the fuel pump.. as far as the stock turbo mani i dont want to spend $2500 for a legit one but on the same coin i dont want to get a ssac or something cheap thats gonna crack...

[flatrate]

for that size turbo you can make 450 with e85 with setup you posted. on my 1st rb25 i have a gt35r with 880 injectors one fuel pump with std upgrades and fpr set to 55psi as base and made 485 to the wheels. but you have to know someone who can really tune e85 cuz its not the same as gas an will not make power like gas. my last rb25 setup i went with twin fuel pumps an 1000cc injectors with a t72 turbo an that was only good to about 515 whp at 18psi. but i changed pumps an was able to go 22psi with alot more fuel and made 653 whp before she blew now im going built block. that will give you an idea what to expect from the fuel and power to made. its not all about the hp you get its more of the tq you gain from using it (IF TUNED RIGHT).

Any dyno graphs pictures?? etc

[nelson8708]

that stock turbo manifold is the choking point for your setup. I'd get some 750's or 880's and call it a day. The detchwerks pump is a 300lph pump, not 400lph. For the price its only competitor is the Bosch 040 or 044. IMO i'd go with the Bosch, it has metal gears while the detchwerks and walbro have ceramic. Under high pressure the Bosch will out flow the detchwerks from the graphs i've seen, however the detchwerks is the only one out of those three that is listed as e85 compatible even though the other two seem to do fine pumping e85 as well. 300lph pump should clear you till around 600whp

thanks for the advice and i must have read wrong when looking at the fuel pump.. as far as the stock turbo mani i dont want to spend $2500 for a legit one but on the same coin i dont want to get a ssac or something cheap thats gonna crack...

I'm helping a friend with his RB build and we are using the stock turbo manifold as well. I would say it once you get past 400whp it is definitely worth looking into a better flowing piece. I've researched the S-tec manifolds and they seem to hold up quite well. That is what we plan to pick up for the 500whp build next winter. For around 400$ its hard to beat something that holds together.

S-tec reviews:

s-tec-exhaust-manifold-overview-t464025.html

[Darius]

I have been seriously considering converting to E85 since the best I can do locally is 93 blended with ethanol. If I converted to E85, I'd get the deatschwerks new 300lph pump because it fits in the gas tank vs. getting an 044 in there will be a major PITA or running it as an external pump. Not thrilled about that. Aeromotive also recently released their new in-tank pump which directly competes with the DW pump. I'd give that consideration before an 044 or A1000 pump as well.

For injectors I'd get injector dynamics 1000cc high impedence injectors http://www.injectordynamics.com/ID1000.html They also offer the pigtails to wire into your harness.

Like others have mentioned, you will run out of turbo and MAF before you max out the aforementioned E85 system.

[meet07]

This summer after my engine rebuild, I to will be running e85 since there is a pump literally 2 minutes down the street from my new house And its also a weekend car. Ive heard mixed reviews about what kind of lines to use but I know they need to be enlarged which is usually why people go ahead and rig up some steel braided lines. There are a few fuel pump combinations that can be used. Ill personally be running 2 walbro 255's hard wired since I already have one and got anouther for free. You have to increase your fuel pressure 30% so you set your base pressure somewhere around 55-56psi.

This is the website I found and used today: http://injector-rehab.com/shop/e85_injector_size.html

Depending on what gt3076 you get your looking at a turbo capable of 525-640 according to garrett. Then if you calculate those numbers your looking at 97lb injectors so you might as well get 1000cc injectors. But then again your looking for like 450whp which is pretty close to 500 crank hp which would be like 74lb injectors. You have to decide.

I havnt put together a setup yet but I found a few useful links that for some reason I cant find right now......

[Darius]

Why are you increasing the baseline fuel pressure? How much boost pressure are you planning to run?

[ItzGenX]

I am guessing it is one of the ways people get more volume out of their injectors. Unless something I don't know about E85 just works better at higher base pressure, I would rather not raise the fuel system past 3 bar. It is what most injectors are flow tested with and built to handle that pressure. A higher base pressure would just mean a larger pressure drop pulse across the fuel rail when an injector opens up. Fuel pumps tend to have a lower flow rate at higher pressures anyway. It is a lot easier for the fuel pump/s to recover from pressure pulse drops at 3 bar than at 4 bar. Now factor in the 1:1 pressure regulation during boost (especially high boost), and you would think that the pumps are pushing hard as it is. Ex: 2 bar boost(it's E85 after all) + 4 bar base pressure = 6 bar total (87psi)! It would be wiser to just buy larger injectors after the overall fuel pump flow has been increased.

[Darius]

ItzGenX, you're pretty much spot on and you had the same questions I did. The reason I ask is because there is no reason to run elevated baseline fuel pressure unless you are concerned with fuel atomization. If you are trying to get more fuel out of the injectors, tune the ECU for longer duration. Unless you're running like 30+ lbs of boost on a big turbo, you should have enough fuel pump with two walbros in parallel, but if one goes down under WOT your motor goes down with it. I strongly advise against running parallel pumps in any application.

Meet07 - Either way, your setup will be adequate. I'm mostly just commenting because I'm curious of how you're trying to tune the fuel and if the walbros will keep up with fuel at the boost you're planning to run.

[meet07]

I was commenting off the little bit that I do know about e85. My freind just got his fully built h2b tuned with some e85 and they turned his base fuel pressure up to 55psi or so. Always read that you have to add 30% more fuel. Im assuming there are 2 ways to get that 30% more fuel right? Turning up base fuel pressure or great big injectors??

I really dont want to use the walbros but I really didnt plan on spending like $1000+ on the fuel upgrades.....At least not this year.

[Darius]

If the fuel pump isn't the limiting factor then go for it, but typically the fuel pump flow will drop off above 30 psi of boost or 73.5 psi. That's why you have to look at the fuel pump curve along with the voltage you're able to run to the pump.

[nelson8708]

Here is a graph that might help you figure out what fuel pump will meet your needs. Credit goes to TryingToTurbo @ ka-t.org for throwing the graph and chart together. Remember what pressure your pump will need to put out under boost depending on your base pressure. 45psi base with 20psi of boost will mean 65psi in the rail.

[Darius]

...and note that the Walbro listed on that graph is the HP version. If you only have the regular walbro 255, the flow drops off with increasing pressure like it fell off a cliff above 70-75 psi like I mentioned before. I would be very careful in sizing your system around those. Maybe put them in now and limit your tuning and boost so you don't over-do it and run out of fuel.

Furthermore, the flow from the bosch 044 looks to be pretty generous in that graph. I'll double check that with another reference I've seen before.

[meet07]

I think im gonna take ur advise after looking at that graph. So what about 255 intake and one or 2 bosch 044 out of tank?

Thanks Nelson

[nelson8708]

I dont like series fuel pump setups because if one fails the system fails. Say the walbro goes the bosch wont be able to pull fuel through it and if the bosch fails the walbro wont be able to push fuel through it. Since you already have a couple walbro's i'd just run them parallel in the tank and call it a day. You might have to get a bigger return/feed lines with that much flow (not sure?).

[Darius]

I have to disagree with you on that one nelson. Although I do agree that if the walbro fails the bosch won't see any fuel and the engine will stall which doesn't hurt anything. And the odds of that happening with the surge tank going dry under WOT are very slim. This is the safe way to install dual pumps.

However, if you are running parallel pumps and one craps out, you won't be able to tell while driving normally. When one is broke and you unknowingly do a WOT pull, your motor instantly goes lean and knocks HARD. Hopefully it doesn't break rings or ring lands but in a stock bottom RB25, it probably will.

You won't need more than one bosch 044, period. A walbro feeding a surge tank feeding the bosch is good for 700+hp on E85. The down side is you need to mount it outside the tank unless you are a contortionist. Maybe CarlH actually got it to fit in tank, but I can't remember on that one.

To calculate the flow from two walbro 255 HP's, take the flow at 43.5 psi (255 lph) and multiply the pressure by the number of pumps in series. 2x43.5 psi=87psi. So two walbros in series will pump 255 lph at 87 psi. 255 lph will supply 700cc/min injectors at 85% duty. That setup will be good to 43.5 psi boost. In reality, you'll probably only run 25 psi max, so you have some additional flow available if you extrapolate the 255 curve back to 43.5+25=68.5 psi assuming it is linear to the left of the original curve (265 lph=866 cc/min injectors @ 85% duty).

[meet07]

After going to this site http://injector-rehab.com/shop/e85_injector_size.html I punched in

-550 for flywheel horsepower which after going through the diff/transmission should be close to 500whp
-6 injectors
-bsfc is 0.5
-duty cycle is 0.85

and I got 566cc/min which is 54lbs injectors.

Then it tells you to take the lbs(54) and multiply by 1.47 (for e85)which equals 79lbs. That converts to 829cc/min injectors. They sell like 850 and 855cc injectors but if I wanted to make more power in the future wouldnt 1000cc's give me more head room??

Im still kinda iffy on the pump setup. They say that the 044 is good up to 700hp....but is that with e85 in mind?? Is 700hp just that...700hp wether its with 93 or 105?? I was thinking that if I used one pump that it would make things safer. Meaning that if the pump died on me it would harm anything. But then if the pump gets weak it could kill the engine. Isnt this the same cenerio with 2 pumps?? One fails and you in the same boat as far as running lean??

[Darius]

A 1.47 factor for E85 is super high. The highest number I've seen for E85 is 30% more fuel. Most say 20% extra is adequate. So you go from 832 cc/min to 679-735 cc/min. If you are only shooting for 550hp, just go with 740-800 cc/min to be safe. They will idle better than 1000's.

And regarding the pumps, one pump and two pumps in series will result in the same symptoms if a pump goes down. The car will stall out.

A single bosch 044 will pump 265 lph at 36.5 psi of boost. That is equal to 4,416 cc/min. Divided by 6 injectors is 736 cc/min of fuel per injector. 85% duty would be 865 cc/min injectors. IMO if you are going with an external pump and aiming for 700hp+, don't screw around. Just get an Aeromotive A1000 and call it a day. They're not that expensive and vastly out flow the 044. Since you're not at that point, just go with the walbro and bosch in series or two walbros in series and tune it until you are out of fueling.

[meet07]

Thats what I was thinking...2 walbro's would help that pocket out. Allow me to spend money else where for now. I knew you was gonna recommend the a1000 and your right...Im not to that point yet...lol Someone was telling me that diffrent pumps sell diffrent grades of e85. Is this true??

[Darius]

Not that I know of. E85 means it contains 85% ethanol. I don't know of any other grades. Now there are differing concentrations of ethanol in ethanol blended gasoline ranging from 10-15% ethanol by volume. Maybe that's what he was thinking of??

[StricNyne]

kinda off topic, but why not run METH i do and i love it and its cheaper as hell