gymnasty

iTrader: (6)

Thanks mike. So what your saying is that I can run e85 all day with setup but at what cost? Won't I be maxing everything out injectors/fuel pump /turbo etc. And how much power will I make like that apposed to bigger injectors and double fuel pumps. Thanks

CO_VR4

iTrader: (83)

I'd be concerned about trying to get 30% more volume from a Walbro 255, unless you're at low boost. The reason is that by the time you increase the base pressure enough to get 30% more fuel volume, you'll be "squeezed" as the boost increases and you have to continue to have the Walbro flow 30% more fuel than you would with gas, because the flow goes DOWN as the fuel pressure goes UP. Since you would have already taken some of the "headroom" out of the pump by increasing the base pressure, you won't have as much margin as the fuel volume goes down with increasing boost...

I've not done the specific calculations for the Walbro, but the fuel pressure/volume curves have been published in the AMS fuel pump thread a few years ago. You can take a look there to see what I'm talking about.

gymnasty

iTrader: (6)

Hey VR4 thanks for your input I was told something similar to what you just wrote.
what do you think ill need to run E85 the right way. Bigger size injectors, another walbro fuel pump, arp head and main studs? Thanks again

AWD Motorsports

iTrader: (211)

Youll only be maxing out the injectors and fuel pump if you choose to reach that HP level.. My point is you need a HP goal then you can determine what youll need to support that HP.. asking if you can run stock injectors on e85 of course you can but you cant make 400hp.. so you need a HP goal to build the car around

Btw.. you added more parts to the car and still have not tuned it??? I see IM and TB on your mod list..

Mike

gymnasty

iTrader: (6)

Mike I wanna make 400 whp/wtq no more than that. I'm sure I can make more but wanna stay conservative.

Edit: yes I was planning on getting tuned next week on pump gas but i had a change of heart and now i want to go E85 I recently added a BR throttle body, ported EM and ported IM but keep getting fuel cuts at night time if I get on it.

CO_VR4

iTrader: (83)

Both Mike and I are correct -- just looking at different sides to the same question.

If you're satisfied with staying within the flow parameters of your Walbro 255 (which will not allow you to maximize the benefits of E85, since you'll have 30% less HP than gas at the same flow levels), then you're fine with your current fuel pump setup. I'm assuming that's not why you want to change to E85

If you want to maximize your use of E85, then you'd need to determine the HP goal you're wanting to achieve, like Mike said, and work backwards from there -- for a given HP, what fuel volume do you need to make that HP level? what fuel pump combination would give you that capability? Bosch 044 external, fed by internal? Buschur or similar double pumper? at your target HP, what likelihood will you need head studs for safety? better connecting rod bolts? those questions are the logical progression to make good decisions about your build.

AWD Motorsports

iTrader: (211)

Getting on it probably NOT a good idea untuned.. Next time you get on it you may end up getting on a tow truck for a new motor..

gymnasty

iTrader: (6)

Well you guys already know my setup and know how much power I wanna make (400) so whats next?
Bigger injectors, another 255 FP, head studs, fuel rail, cams, rods? I'm not looking to spend money on something I don't 100% need. Thanks mike and VR4

AWD Motorsports

iTrader: (211)

Injectors is all you need to make 400hp..

Mike

gymnasty

iTrader: (6)

Thanks mike I know there's probably a dozen or more brands of injectors out there. What size do you recommend and brand?

AWD Motorsports

iTrader: (211)

I suggest the 1200cc PTE injectors for your goals.. They will work even in the future if you want up to 650hp with supporting mods..

gymnasty

iTrader: (6)

You think 1000cc will do the job just as well? Reason I ask my buddy is selling his 3 months old pte 1000cc for cheap since he needs to upgrade to a bigger size.

CO_VR4

iTrader: (83)

There are a number of fuel injector size calculators on the internet that you can experiment with. Here's one from RC Engineering, a well known fuel injector company: http://www.rceng.com/technical.aspx
It assumes GAS, not E85, so increase the calculations by the approximately 30% volume increase needed for E85. Also, there are some variable assumptions in these calculators, so be conservative on the inputs, so you drive a result that errs on the side of caution.

Using 450 crank HP to get 400 or so wheel (dyno) horsepower, 4 cylinders, .60 BSFC, and a max injector duty cycle of .8, at 43.5 PSI base pressure you'd need just less than 900cc's of volume (on GAS) to make that HP. Add 30% to that for conservative injectors for E85, so about 1200cc, where Mike recommended.

People can make that HP on less injector, but you end out maxing out the injector, raising base pressure, and other work arounds that are not optimum and may limit your future expansion. If you can live with a lower max HP, and never make another HP upgrade, that's one thing. Most people find that's not realistic, and then have to get a bigger injector (again).

Here's a thread that has different people's experience with sizing injectors that may useful for sake of comparison. Almost any good shop has or can order any of these injectors for you, not just Mellon, but the info is good to see what other people are getting out of different injector brands and sizes:
https://www.evolutionm.net/forums/ev...-can-help.html

gymnasty

iTrader: (6)

thank you VR4 and Mike for clarifying and schooling me on what is and what isnt.
ill do some reading on the links you guys provided. thanks again