I've recently thrown another spanner in the works...I'm considering upgrading my fuel system to support E85/flex-fuel. I'm certainly not committed to the idea yet, but I'm thinking about it.
 
The idea suddenly crossed my mind when I realised that it would probably be easier to upgrade the fuel rail and injectors when the intake manifold is being swapped over.
 
My Adaptronic ECU has complete flex-fuel functionality when a suitable sensor is installed. If I upgraded now, I would basically have to get one dyno tune on 0% ethanol (normal premium 98 gasoline), and another dyno tune on E85 (85% ethanol), or maybe 70% ethanol depending on availability, then my ECU would interpolate the fuel enrichment and additional ignition advance to handle any in-between ethanol concentrations. I could optionally get a third dyno tune at about 30-50% ethanol concentration just to make sure it's all good in-between, but I doubt I would bother.
 
In hindsight I wish I'd previously anticipated the possibility of upgrading to E85 later, so I could have had a more suitable fuel pump fitted when it was changed the first time. I currently have the walbro 255lph one, which wouldn't flow enough (marginally I think), and may not be ethanol compatible anyway, I'm not sure.
 
My existing 800cc/min side-feed injectors and fuel rail would also have to be swapped to 1200+ cc/min injectors with a top-feed fuel rail. I could get a kit from RacerX and add it to my intake manifold order. 
 
Has anyone on this forum had experience with E85/flex-fuel on an SW20?

I don't have first hand flex fuel experience on the SW20 though I had planed on running it.  The issue with injectors in the 1200+ range is most of them, quite frankly, suck.  I bought ID2000's for my E85 build.  Probably bigger then you'd require for your aspirations however they are a far better performing injector then things such as the 1600CC bosch injectors of old.  Fuel pump is a serious issue.  Not only are you going to need ~30% more fuel straight off the bat due to E85 but I would dare suggest you'll end up be tempted into making a bit more power as E85 will safely allow it.  This means more fuel again.  This leads to a can of worms.  Basically you'll have to run a multiple intank pump setup (couple of stealth 340's or whatever they are perhaps?  If they are E85 compatible) or run a large external single pump.  My general experience with external pumps wasn't so great and I personally probably wouldn't buy another aeromotive pump for my car again.  The SX performance external pump I used was better, however, still suffered cavitation issues after lengthy stints on the dyno and I'd say if you intend on driving it for more then an hour or two straight you'd want to install a fuel cooler in the return line.  I was eventually going to use a weldon pump and deadheaded fuel rail to keep heat out of the pump.  The weldon pump isn't a flow through design so doesn't add additional head to the pump through the fuel cooling the electric motor.  The dead headed fuel rail stopped fuel that had been heated by an aluminium fuel rail attached to a hot aluminium head from returning back to the tank and heating the fuel.
 
I found fueling as one of the biggest pain in the arses in my MR2 build.  Getting something that would work reliably just wasn't that easy.  Another alternatively is running a low pressure lift pump to a surge tank in the boot and running an external pump (couple of bosch motorsports or something, if compatible).  This is cool provided you are happy to loose boot real estate.
 

I considered going flex fuel on mine but think I will just stick with straight E85. I brought a RacerX fuel rail and ID2000 but got stuck with what pump/s Im going to use. Thinking most likely it will be twin intanks. Be interesting if you go ahead as what you end up using. I dont see mine happening to soon so just going to put the spare gen3 in for now till I get everything sorted 

Rob, I think Walbro do a 400lph pump now.  They have just released a E85 compatible version, per http://www.hptautosport.com/store/fuel-system/fuel-pumps/walbro-400-lph-e85-fuel-pump-w-install-kit
 
I don't know too much about the pump so probably best reading up some user reviews first.
 
May fit intank?  I know evo users had to mod up there fuel pump carrier to get it to fit though as its too big.  That in a single pump configuration should be OK for your goals.

I just saw on MR2OC there is a guy who made an impressive 480rwhp on E85 (GT3071 at 26psi) with only a 255lph Walbro. He has 1200cc injectors.
I'm guessing that my Walbro 255lph fuel pump isn't E85 compatible anyway, so the 400 Walbro would be good if I can fit it in the same location.

Yeah, dynojet numbers no doubt :P

Come on Rob max out that GT3076 !
I see 350rwkw+  in your future.

RacerX just told me that my intake manifold is ready to ship, so I need to hurry up and decide about this Flex-Fuel idea.

Just do it

Make sure its convenient for you to fill up or have the fuel delivered.
Otherwise it will be a massive pain.