You should try some searching. I guarantee you others have talked about this and have done this before...
On a side know, it isn't exactly what you want to do but it's similar.
I'll quote BLKMGK from the above page...
"Alright, I've been kicking around the idea of running two fuels lately. Now that I've spent some quality time running race gas I think I like it! But I don't want to spend HUGE bux on race gas when most of my time is spent in traffic or waiting to go WOT. I want to have my cake and eat it too.
So, here are some ideas I've got concerning fuel and some other's have shared with me.
1) Methanol. Half the price of gas but you use twice as much. GREAT cooling and it's supposed to be pretty tolerant of a wide range of A/F ratios so tuning isn't so bad. I run some now but what I have in mind needs to be more exacting in it's delivery I think. A HUGE downside of meth is it's corrosive as all get out icon_sad.gif
2) C16 - now we're talking. icon_twisted.gif Expensive but if we could run it only when we wanted it the it's not so bad right? Even the fact that it's leaded isn't so big a deal if pump is in the tank fulltime otherwise.
Okay, so I think I want to use gasoline. I sure as heck won't be pushing this through a Shur Flo pump and a nozzle! So, that leaves me with injectors. I have a six banger so I want six injectors. I think I can mount them as secondaries under the intake runners.
Problem #1 We have 10 injector drivers assuming none are used for other things. I'm at least two short! Can any of the other I/O be modified to become injector drivers? I'm going to search for the posts on the AEM racecar, I'm pretty sure they run more thna 10 injectors.
Solution A) Pair injectors that are run secondary. If they are low impedance then I think pairing eliminates resistance issues. I'm not sure if this creates issues with synching firing with valve opening. I think if the pairs are chosen carefully that this will work without leaning a cylinder - at WOT we're flowing like a river on closed valves anyway, right? I'm not sure icon_sad.gif I think the AEM NSX motor does this - need to find those posts!
Solution B) This is Arnout's idea so I hope I can get it right icon_wink.gif Use a 7M resistor box since that car fires in pairs of parallel injectors. I'm not 100% clear on how much I/O this requires yet but he thinks it will require less than the three I was going to use for my idea - maybe the 7M batches? His idea is to toggle power from one resistor box to another at some specific low(ish) load so that we change out injectors all at once. We surmise that an injection cycle might be lost but that it would be okay - thoughts?
Anyone have any other whacky ideas to fix this part? icon_biggrin.gif
Problem #2 - my car is a street car. No fuel cell and I actually like to store my targa in the hatch from time to time. I don't have a spare back there though so maybe a custom tank where the old spare used to go? I'm not sure how to solve this one. It has to be safe no matter what and have enough volume to be worthwhile. Slosh and fuel level warning are concerns too. ATL makes a spare cell for Porsch I think - I'll be looking soon.
Problem #3 - pumps! Again, a street car. So, if I run a second tank I still need to be able to move some SERIOUS flow. Dual Walbros are in my main tank and something similiarly high flow in my secondary would be required. I don't think I've seen many cells setup for in-tank pumps let alone one that will fit in my spare tire well icon_sad.gif External pumps are a thought but all I've worked with have been loud as hell and unreliable. Any ideas on how to best solve this?
Some random thoughts...
I'm considering putting the pressure regulator in the back so I need only run a single line forward. Just bypass fuel not needed straight into the tank. This will obviously not be pressure referenced which would complicate tuning - I'd probably have to run a HIGH base pressure too. Thoughts?
I'm wondering if I could run say 1Kcc injectors as secondary but modify the Boost Comp table to make up for the flow difference. I would then retain the same fuel columns I do now running Boost Comp'd. Arnout feels there might be an issue here because the injectors will certainly be of different flow. Neither he nor I can put our finger on what exactly the impact might be here.
Thoughts?
Arnout is running an Eaton supercharger from a Mercedes SLK to pre-spool his T88 turbo. It has a magnetic clutch and is drawing through his turbo in order to aid spool up to a few PSI at which point the blower bypass kicks in. Pics can be found on
www.supras.nl and he posted some to Supraforums too. I think that is bad ***! Did I mention it's in a MKII Supra and will be running an auto transmission and solid rear with switchable spool icon_eek.gif SIIIICKKK!!!! icon_twisted.gif
Whew - done rambling. Start shooting holes in my ideas. Maybe someone is already doing this?"
