Jump to content
SAU Community

Recommended Posts

Quick report -

so far done about 220kms, used about 35 litres of the stuff! Shitehouse economy! Maybe the oxygen sensor for the ECU can't tell its got 10% more ethanol in it, much the same of the dyno's...... so its adding a extra 10% to light load cruise?

Knock levels about the same

  • Replies 47
  • Created
  • Last Reply

Top Posters In This Topic

The O2 sensor doesnt know that you've got ethanol in it, but it will detect the leaner mixture and the ECU should compensate somewhat.

Ethanol has a lower calorific value than petrol, so basically the SAFF stuff (or any other ethanol mixed fuel) has less 'bang' or energy for the same amount of petrol. Thats why your economy is suffering, and is one of the major downfalls of ethanol mixed fuels. Usually the economy drop is roughly 2-3% in most cars for a 10% blend. If you're suffering much more than that, then something is wrong...

So IMO the bottom line is that you're not really saving money on ethanol fuels, unless its able to at least compensate on the pump price with respect to the fuel economy loss. That means roughly 5c/L cheaper. I'd have no problems using it in your average 10 year old car I guess, but I dont see the point using it in our cars.

Edited by Busky2k

that's what I thought too busky

Your car will only use more fuel in closed loop ie cruise/constant speed where the ecu detects leaner condition and add extra fuel. In open loop it won't know which fuel is in there.

The added avantage of this fuel is better knock retardation. So you can run more boost/timing safer. If you want more power you wil have to fill up more frequently :D It's part of the game unfortunately.

Well over all, I got 370kms out of a tank. The last hundred odd kms was just off boost driving around really.

Economy wise it went pretty close to what I usually get out of a tank of BP/Mobil, maybe 30kms less

I'd say overall, its not any better in regards to performance, knock levels where pertty similar.

I guess the jury is still out, need to do a bakc to back dyno to see if its any better

But, from what I experienced, if you where stuck, and needed to fill up, it would do the job pretty well

Hmmm. The only issue I have in terms of 'knock retardation' etc is that if the petrol is rated at 98 RON, is it tested including the ethanol? If 2 fuels are 98 RON rated, and one is ethanol blend, then neither should have advantage over the other.

SAFF would theoretically allow MORE timing if they start with a 98 RON base and add ethanol, rather than a 96 RON base and then adding the ethanol to make up to 98 RON. (Ethanol has an octane rating of ~110) Might be worth firing off an email to SAFF to see which option they take to make their 98 stuff.

Edited by Busky2k

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • You know, that is exactly the thing that I was thinking a coupe of hours ago. I even had a plan for a meme, involving one big one, another big one, and the Old El Paso girl saying "¿por que no los dos?"
    • NoS, 2 of the big ones.
    • Oh, that's grim. Something bad has been happening there.
    • Put an endoscope down the hole and saw this. Not quite all around the bore but a good 60% at least. Chin to the chest and towards further disappointments I guess.
    • 2 does "sort of" applies, maybe......but looking at what parts would be needed for the swap to get engineered, registered, and insured, and basically that's everything under the car, the modifications the make it legal would be problematic and horrendously expensive, all for a street car that just cruises around and hits a few twisty roads on the weekends Also, from looking at the NSW rules and Regs, with all modifications that is required just to make the car safe and not twist itself to pieces, and then actually get registered for street use, may still be impossible nowadays As for 1, when you add in a fresh engine, fresh transmission, rear cradle and diff, tailshaft, suspension, brakes, cooling, and all the other fabrication required, your probably looking at up to $100k to do it right, all for a 20 year old MX5 that is over engineered and you would never be able to actually use the power it has on the street, much like your beastie, which I love, but you actually track that thing and can use all of its powers in anger, in a safe environment  Hell, the old Bogan Cruise Ship had more power than I could use on the street, and in hindsight, I went a bit silly on that thing, it didn't really need the 500hp it had for what I actually used the car for, it was fun, but basically unusable on the street if you value your licence  As for cams, yeah, I'll probably book it in for them to get installed and tuned soonish, like next month after MX5 Mania are back at work....... and yes, I've already sent a email to bin the turbo quote and quote instead to install cams and a new Fluidampr balancer that will suit the 2.5 better than the OEM 2.0 balancer that is swapped over for the 2.5 install, as the balancer needs to get pulled to time the cams it's a while your in there sort of thing I did think a bit about flex fuel for a laugh, but being na, and no where really around locally anymore to get E85, I've binned that idea, so no sweet sweet corn smells are set for the car I wish E85 was more of a standard fuel, it's better for the environment, better for tuning, plus that sweet sweet smell we all love As for fitting in the family, that's not needed, as everyone in the family already owns a car that can seat 5 humans comfortably enough, the MX5 is "my toy" As for buying a car that is already built, nah, I would rather pick and choose my parts, I enjoy the process, and in the big picture, the additional cost is well worth the enjoyment, and the occasional frustration, I get out of doing it, albeit with other people spinning the spanners, and me, just paying the invoice 🤣
×
×
  • Create New...