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Yes 20% sounds a bit more manageable than 85% and it wouldn't be that hard to blend using suitable amounts of E85 here to get an 80/20 split .

It would also mean injector size would not need to be as big as an E85 burner would need .

I gather you "turn" side feeds from 370 to 650 by removing the 4 hole wafer to expose the single pintle valve .

A feller here from the classic SAu side is setting up to race a DR30 and is prepared to swap me some RX7 turbo injectors , I think 460 high impedance and 550 low impedance 11mm O ring injectors , for my old DR front struts brakes etc .

The 460's would be a bonus because they are high impedance which is what suits the Vipec V44 and Link G4 Storm . I'm told you have to buy and wire in the separate peak and hold injector box to run that type of injector .

Anyway I doubt this engine would like much over 200 Hp on a daily basis and 460's could probably do that even with E85 .

I just need to have a few shallow barbs machined into the top sections of these O ring injectors to reliably clamp a high pressure EFI rated hose to .

Actually just on ULP I've been doing a bit of digging on the burning characteristics of the various octane types and I think it's a little known fact that the lower octane ULP is better than the higher octane stuff at everything except suppressing detonation . It could actually be possible to get a better brew blending ethanol with more mundane 91 or 95 ULP so long as you get enough octane to stop the detonation .

It was explained to me that the additives used to make say 98 ULP detonation resistant makes it harder to spark ignite than say 91 ULP and it tends to make it burn slower as well . The person said the low octane stuff burns at a faster rate and slightly higher temperature so from a cylinder pressure perspective alls good - until it detonates .

It would be REAL interesting to see how much extra ethanol it would take to stop 91 ULP from detonating under high loads or whatever .

The price alone of 91 ULP with lets say 25 or 30% ethanol content could be quite friendly . I'm only guessing that 5-10% extra ethanol over the 98 ULP/E20 would give the same detonation resistance but there would be an overall octane equivalency point somewhere .

For the fist time in a lot of years I put what I though was poverty pac fuel (91 ULP) in my daily just to see what would happen , it hasn't pinged yet so while its in a quite soft state of tune and the engine fresh higher octane fuel won't make it run better and maybe slightly worse than it could . Such is life .

Lets know what you think and how things go , cheers Adrian .

I have tried a few brews of Ethanol, mostly when Shell V Power Racing (100 ron) disappeared.

The 60% 98 ron and 40% E85 was interesting, which is actually 60% 98 ron, 5% 92 ron and 35% Ethanol. It makes around 100 ron and it was particularly effective in an R33GTST with the default Power FC tune. No detonation due to the high ron and it leaned out the normally rich Power FC tune due to the Ethanol content ie; around 10% leaner. Normal starting and no high temperature fuel vaporisation problems which I sometimes get with 100% E85.

The other brew I found useful was 40% 98 ron and 60% E85, which is actually 40% 98 ron, 10% 92 ron and 50% Ethanol.. So it’s pretty much 50/50 petrol and ethanol. It makes a very useful 102 ron, but the main gain was lower exhaust gas temps for track days. That’s the extra Ethanol at work there. Again normal starting and cold running but it did need careful tuning. It was a handy mix as no injector upgrade was necessary as there was just enough head room. It picked up a noticeable amount of torque due to the additional ignition advance we could slip into it. Particularly from idle to around 5,000 rpm and you could easily feel the faster throttle response.

Cheers

Gary

A feller here from the classic SAu side is setting up to race a DR30 and is prepared to swap me some RX7 turbo injectors , I think 460 high impedance and 550 low impedance 11mm O ring injectors

The 13B turbo injectors are rated at 550 cc's but actually flow around 570 cc's at 36 psi and they are high impedance (13 ohms). That's what's in SoSK's R33GTST and at 3 bar (45psi) base fuel pressure they are at 65% duty at 266 rwkw.

Cheers

Gary

Hi Gary , I'm no RX7 Turbo expert but a bit of research leads me to believe late 80's ones had primary and secondary injectors - the primaries being 460 and the secondaries 550 + .

Pics I looked at showed the rectangular plug injectors have that locating tang in the middle on low impedance injectors and offset on high impedance ones .

I think an 1800cc engine with small inlet ports and siamesed exhaust ports would be doing well to run 460's to the limit in a road car .

Anyway should have a small army of injectors to play with and if I can get suitably sized high impedance ones and convert them to hose tail type alls good .

Do the RX injectors have good spray patterns ?

Cheers A .

BTW OT but GCG came through with that 52T GT3037/GT3076R and there are pics of it in my "SR20 Tuners Opinions" thread .

Depending on the ratio you could try a lower octane ULP , remember all extra octane in ULP does is make the fuel MORE difficult to ignite and that means for the ignition system too .

All you need octane wise is enough to prevent detonation and that's all , any extra in the ULP is a disadvantage not an advantage .

My sputnik Subaru EA82T engine gets better fuel consumption on 1/3 95 ULP and 2/3 91 ULP than it did on 95 or 98 ULP , it feels better doesn't detonate and costs less too . Bonus ?

If it's not rattled neither am I , A .

BTW Sunday Terrorgraph mentioned that the General is yet again interested in introducing flex fueled Oldens across the range next year - always next year isn't it ?

I'm not out to buy one but there is the potential to push for greater E85 availability and a source of E85 compliant fuel system bits for parts sl*ts - like us . Need an in line water separator I reckon .

Edited by discopotato03
Depending on the ratio you could try a lower octane ULP , remember all extra octane in ULP does is make the fuel MORE difficult to ignite and that means for the ignition system too .

All you need octane wise is enough to prevent detonation and that's all , any extra in the ULP is a disadvantage not an advantage .

My sputnik Subaru EA82T engine gets better fuel consumption on 1/3 95 ULP and 2/3 91 ULP than it did on 95 or 98 ULP , it feels better doesn't detonate and costs less too . Bonus ?

If it's not rattled neither am I , A .

BTW Sunday Terrorgraph mentioned that the General is yet again interested in introducing flex fueled Oldens across the range next year - always next year isn't it ?

I'm not out to buy one but there is the potential to push for greater E85 availability and a source of E85 compliant fuel system bits for parts sl*ts - like us . Need an in line water separator I reckon .

Why not just use a higher petrol mix rather than using lower octane petrol?

standard

doing an oil change asap and will send a sample of the old oil off for a UOA

brads, disco explained why it's actually beneficially to mix with a lower octane rated ULP

standard

To point out I am yet to touch this e85 stuff so have been reading up, dangerous i know.

So don't take below as me telling anyone anything ....

In my reading standard fuel lines are not the best option. E85 will slowly eat out a rubber hose.

Using a synthetic based hose it supposed to be the go.

I have had problems with rubber and braided hoses over time with race fuels. So keen to not have the same issue with e85.

I would expect E85 to be simular ?

So if you were going to upgrade your fuel line material what would you step up to ?

I was using standard lines, all good.

How long for ?

Did you inspect the inside of the lines at any stage(split them open) ?

The telfon coated lines are good but I have had them fail over time under race fuel.

Quite an expensive to be replacing all the time too and really you need to replace them well before they fail.

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