well the price is much cheaper, plus simplicity, you only have 1 pump that can fail. If that 1 pump fails your car wont start, where with dual pumps if one pump fails you wont know until u blow your engine

 

or you have a proper ems with primary fuel pressure variance, O2 lean limit, and primary injector duty limit failsafes.

my 2nd pumps doesnt kick on, car doesnt boost and hits a rev limiter.

 

Exactly. I can certainly understand the pursuit of a cheaper alternative/option to the CJM twin pump, but the safety argument isn't valid when using a sufficient stand alone EMS with the appropriate failsafes.

 

running 800cc injectors with a 340 pump on e85 will yield roughly the same fuel flow equivalent to 600cc injectors on a walbro 255. This is due to the extra fuel requirement for e85. That being said, if you max out 600cc on a walbro 255 and want more power you aren't going to push much more than the current power levels. The extra you will get would be from the cooling effect of e85 but i'm really not sure the small increase in power (due to fuel flow restrictions) will be worth the extra cost of the fuel.

Cut corners.

If a walbro 400 actually can push 400LPH continuously then it still falls 120LPH short of a cjm twin pump. So it will fall quite short of being a "big power" e85 build. Could it maybe pull mid 500's or even close to 600....possibly. You can do that on pump gas as well for far cheaper cost on both equipment and fuel price. So you have to calculate will I be making enough power to actually warrant the use of e85 since i'm not going big with the fuel system.

To me e85 isn't worth the headache and cost per gallon for only 550hp.

 

depends where you get it from, back in ohio e85 was about half the price of premium so its actually cheaper. sure it does require more fuel but if your in a area like that then you get a 114(depending on time of year) octane for 3/4 the price for 93(half the price +30% more fuel consumed). you also get a little bit more power not just from the cooling effect but also being able to run more spark advance, granted in any situation you need to have a capable fuel system to max the effectiveness of it, but it has shown gains pretty much on everything it has been tested on.

Edit: something i forgot was its an oxygenated fuel, so similar to q16, so you are actually forcing more oxygen into the chamber making more power from a third source(cooling, higher octane so more spark advance, plus oxygenated.)
all in all i cant see why a person wouldnt run it if they have a reasonably priced source of it. yah you have to run a bigger fuel system but you WILL make more power then pump, and can run your turbos at higher boost in a possibly lower effeciency island due to the cooling as long as you havnt hit the max airflow of the turbo.

 

There is no reason to play with small injectors when 1000cc and 1200cc injectors work fine for street, daily driven use and the prices are all pretty much in the same ballpark (I think). HKS 1000, ID1000 or PTE1200s? ID2000 for big power, but no stoich/stock idle.

So it's really only a pump issue. I would run e85 if it was widely available/convenient. I could get rid of the complexity of W/M injection.

 

when converting to e85, there is no point in doing it unless you design your setup so that the fuel system is NOT the limiting factor. RFS, large injectors, and a twin fuel pump setup are necessary. If for whatever reason you don't want to run the CJM twin you could do an inline fuel pump like the a1000 or bosch in addition to your walbro 400lph.

 

^ what about an aeromotive 340 or walbro 400 at 20 volts? I think for most ~600 whp builds it might be a practical alternative.

 

personally, and ill admit im biased, i think putting that much money into a fuel setup it needs to be done right with a swirl pot. i have probably 2400 into my system(rough guess because i cant remember what i bought my PTE1200 injectors for from blackbird), thats for walbro 255 into swirl pot, dual exit from swirl pot into dual bosch 044's, stainless -8an to rails(way overkill), injectors, rails, fpr, -6an from fpr back to swirl pot, then -4an overflow from swirl pot back to tank, as well as all the mounting hardware and 40 micron filters after the bosch pumps. theres a bit of work myself in there also though such as installing everything and making my own lines, also not counting the tools i needed to pick up that i dint have anymore. i wish i could get e85 on island but apprently the only place that has it is the marine base and its only for mil vehicles.

 

Ya thats some serious over complex fuel system for just pump gas.

 

i set it up so i never have to worry about starving the engine in corners if im not running alot of gas in the tank, which would be most of the time racing for less weight =P but once i get back stateside i intend to to run e85 and switch the meth nozzles to the smallest ones available spraying 100% water, and use it just to stop any possible preignition that might happen with the e85.


plus this is actually the "correct way" to set up a fuel system for the exact reason of preventing fuel starvation from high g's

 

which tracks do you race on? have you ever experienced fuel starvation? Sounds like you have. Thats a big problem in the 370s, but not heard much about it with the 350z.

 

can you elaborate on that? why fuel problem on the 370z??

 

they use a totally different fuel basket setup. Its subject to fuel starvation when racing at the the track. You'd never have an issue on the normal roads though

 

I see, I never looked into the 370z stuff

 

Well, good thing I've only used my 370Z for daily driving and commuting!

 

i experienced it in my 84 camaro at the drag strip when running low fuel(completly stripped 500 hp roughly running drag radials and mayby 2600 lbs thing was a bucket even cut out extra brackets and sheet metal inside i dint need this is actually how i melted the piston combo of this and running only 3 degrees timing then stock lol), and occasionally just fooling around in abandoned parking lots in my 2000 camaro(pretty much stock but you would watch the gas guage go right to empty and the car would sputter almost dieing), i havnt done anything yet in the z because of training, deployment ect. ive only driven it about 1000 miles in the past year and a half ive owned it.

but im planning ahead and trying to eliminate any potential problems i might have, especially since its something i have had happen to me on other vehicles never hurts to be prepared.

i guess its kind of like a dry sump system, do i need it? probably not, could it happen? definatly. just a little bit of insurance, who knows if i go for more power i might convert to dry sump down the road haha, hoping this paper work goes through to reclass so i get moved to arizona for training. then ill be able to start hitting up some bigger tracks, hawaii blows for racing just some small stuff down at the stadium which i dont have much interest in.

 

The 370z suffers serious fuel starvation problems when exiting hard right turns. Its bad enough that in a completely stock car on stock tires you can starve the car and actually end up on the side of the road stuck with all the fuel on the drivers side saddle, and the car wont start because the siphon is of course powered by return fuel, which there is none of if the fuel pump has no fuel to begin with. I had it happen to me. For that platform, we have in testing and prototyping an in-tank surge can system to solve that problem... will be available this spring. I believe the problem is due to the much deeper fuel tank in the 370z, dividing up the sides of the tank more prominently.

The 350z does not have the issue, well... not nearly as bad as a 370z. A 350z on the street will not encounter starvation for the most part. Not in my experience... I ran my 350z on big r-compound tires and never encountered it no matter how hard I pushed it. While I never went extremely crazy on the throttle at low tank levels and hard rights... I did go full throttle plenty of times with the low fuel light on, over 500rwhp, and did not encounter starvation.

As for the Walbro 400... the pump in itself is a great alternative to a pair of 255's. However, so far I have seen evidence that the stock fuel pump assembly itself is too restricitive to take advantage of the 400. But more testing and examples need to be out there before I can make that a statement that I would stand behind.

I can understand why anyone would want to at least try it out... definitely more cost effective and more simple. You will probably want to setup a relay and power wire for a pump that size... so if you ever have to move up to the twin pump, at least that part will already be taken care of!

Depending on some testing with our 370z stuff (our intank surge can is setup to house a walbro 255 as the primary pump, and a walbro 400 as an optional secondary pump), we may make adjustments to our 350z/G35 twin assembly to also use a walbro 400 as the secondary. I think that our intank surge can for the 370 would be of great interest to this community (especially road racers), but it really takes advantage of the much greater depth of the 370z tank to create its displacement. It wont be too hard for us to modify one to the depth for a 350z/370z and testing though.

 

Price has gone up a bunch. My room mate is from ohio so prices from ohio, indiana, and missouri are all about the same. 3.29$ per gallon e85. Only about 60 cents cheaper than premium and eats up about 1.5x the fuel so roughly 4.50$ for e85 when you calculate it mile per mile (based on how much i spend per tank for the same mileage on e85).

It's by far not a "cheap" alternative for pump fuel but compared to high octane petroleum (race gas) it is far cheaper. What i was getting at is the person using walbro with 800cc injectors will be limited on power due to fuel flow. If you are going to limit yourself to a power range which can be had by regular 93 octane then it's a waste of money to make the switch.

 

I partly agree. Using my 370z as an example... mid 500s at the wheels is totaly obtainable on the stock engine using 93 octane. But I personally use E85 because it is within the range of a simple fuel system setup for me (aeromotive 340 and 1000cc id's), and I feel a little better about the knock resistence of the E85.

Although, I do have trouble trusting my E85 to be a consistent blend, and I worry about how long its been sitting the storage tank, etc etc.

Example... I called my local E85 source last week to find out if they have the summer blend E85 or winter blend E70 in their tanks. They told me they never switched so it is still E85. Part of me doesnt even trust what they say/know about it, and the other part of me thinks that if it is still E85 down there, is it the same batch of E85 that I filled up with last fall??? Cause I hear E85 doesnt hold well for long term storage (but have not thourghly researched yet).