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No, it comes down to pump fuel being horribly inconsistent and me not wanting to risk blowing up an engine because of one bad batch of fuel.

It's pretty simple to understand.

Horribly inconsistent.. If anything E85 should be quite consistent considering how it is contained at the servo unlike regular ULP and PULP.

There are others running around with 500rwkw (rb30's) without problems and not popping motors. Or is that an rb25 thing? :banana:

Horribly inconsistent.. If anything E85 should be quite consistent considering how it is contained at the servo unlike regular ULP and PULP.

There are others running around with 500rwkw (rb30's) without problems and not popping motors. Or is that an rb25 thing? :D

There's a reason the market for Ethanol content testers has exploded in the states and it's not because it's the most reliably consistent fuel.

Let me put it another way:

If you tune an engine on the ragged edge, would you prefer to use a fuel with 0% difference between batches or 1% difference?

There's a reason the market for Ethanol content testers has exploded in the states and it's not because it's the most reliably consistent fuel.

Let me put it another way:

If you tune an engine on the ragged edge, would you prefer to use a fuel with 0% difference between batches or 1% difference?

True.. However I think you worry too much given your fairly mild setup. :D

Unless that is you are throwing a GT42 or T51r and aiming for big numbers.

The GT35r 1.06. E85 or race fuel with good cams (265-272dur 10.5mm lift) your looking at ~420rwkw (behind a manual) on 20-22psi or so.

Your biggest problem are the cams when trying to make good power 350rwkw+ on reasonable boost levels.

Regardless you should be able to max out the turbo and able to 'easily' crack MTBT due to the GT35's large hot side on both E85 and race fuel. The tune WONT be ragged edge unless you try that on PUMP.

Any 'slight variation' in RON will not matter as you will be far away from the det threshold.

PULP is a completely different ball game as you won't get anywhere near MTBT so any slight variance in quality will have it knocking.

---

My ONLY concern with E85 is the blend variation between summer and winter.

There's a reason the market for Ethanol content testers has exploded in the states and it's not because it's the most reliably consistent fuel.

Let me put it another way:

If you tune an engine on the ragged edge, would you prefer to use a fuel with 0% difference between batches or 1% difference?

Why would you tune any engine on the ragged edge unless your a fool with lots of money.

True.. However I think you worry too much given your fairly mild setup. :/

Unless that is you are throwing a GT42 or T51r and aiming for big numbers.

Nothing wrong with aiming for big (mph) numbers with a 25 and GT35/1.06 combo. The engine combo was spec'd as an example of what can be achieved with a very, very common setup that people can relate to. Not a GT47-equipped dyno queen.

The GT35r 1.06. E85 or race fuel with good cams (265-272dur 10.5mm lift) your looking at ~420rwkw (behind a manual) on 20-22psi or so.

Your biggest problem are the cams when trying to make good power 350rwkw+ on reasonable boost levels.

Power figures only concern me to the extent that they're reflected by terminal speeds. My 5-speed stocker made 265kW on the bottle and ran 120mph @ 3240lbs race weight. Why could so many other similar cars only manage 114-116mph with 300kW? The point here is that I'd be happy for the dyno to show 150kW if it ran 140mph! :laugh:

Regardless you should be able to max out the turbo and able to 'easily' crack MTBT due to the GT35's large hot side on both E85 and race fuel. The tune WONT be ragged edge unless you try that on PUMP.

Any 'slight variation' in RON will not matter as you will be far away from the det threshold.

PULP is a completely different ball game as you won't get anywhere near MTBT so any slight variance in quality will have it knocking.

I'm not concerned with breaking records on PULP. If I was, I wouldn't have stopped tuning at 19psi and 11.xx:1 AFR's.

---

My ONLY concern with E85 is the blend variation between summer and winter.

I've highlighted the word that best describes my argument.

Regardless.

I'm not talking of comparing dyno figures/ET's or breaking records on pulp. :/

Simply pointing out where you may wish to improve if you want to squeeze every little bit out of that turbo.

Those cams are the down fall of the setup its as simple as that.

GT35r is a push over for E85. There is head room for a little variation due to MTBT (minimum timing best torque). I.e push more ignition in you make less power.

The summer/winter variation isn't too much of a hassle and will no doubt be sorted soon as summer approaches. Well at least on the dyno I run on as various track only cars have been setup for use with E85. I'll be sure to share the findings if the variation is an issue.

Regardless.

I'm not talking of comparing dyno figures/ET's or breaking records on pulp. :/

Simply pointing out where you may wish to improve if you want to squeeze every little bit out of that turbo.

Those cams are the down fall of the setup its as simple as that.

GT35r is a push over for E85. There is head room for a little variation due to MTBT (minimum timing best torque). I.e push more ignition in you make less power.

The summer/winter variation isn't too much of a hassle and will no doubt be sorted soon as summer approaches. Well at least on the dyno I run on as various track only cars have been setup for use with E85. I'll be sure to share the findings if the variation is an issue.

What cams are you referring to? The Poncams in my thing? The dyno seems to show that it's flowing well enough in all the right places. We'll see. The biggest problem I can see is that in my area, there's only one E85 servo and it's not what you might call busy or reputable. lol.

Interested in the fuel variation you see on the dyno.

Thanks for that.

The ragged edge is suicidal....! especialy with normal fuel's

With E85 it loses power before it detonates, so if your running on the edge with e85 you have a tune that is soooo far off from making max torque and power its not funny.

Say i would make max power at 25deg, i could turn it up to 35 and just lose power and torque with no detonation with e85 (this has not been tested but I am guessing for an example) :/

What cams are you referring to? The Poncams in my thing? The dyno seems to show that it's flowing well enough in all the right places. We'll see. The biggest problem I can see is that in my area, there's only one E85 servo and it's not what you might call busy or reputable. lol.

Interested in the fuel variation you see on the dyno.

Yeah the poncams. 256 8.5mm lift.

Obviously you want every little kw out of the setup possible (your ragged tune comment) so bigger lift cams are a way of doing this while improving 'reliability' and reducing the RON requirement of your fuel.

You may then feel happier within yourself running E85 and saving hundreds of $$ per tank as its not so 'highly strung'.

All though E85 is perfectly fine due to the huge amount of head room (MTBT) it provides.

My 5-speed stocker made 265kW on the bottle and ran 120mph @ 3240lbs race weight. Why could so many other similar cars only manage 114-116mph with 300kW? The point here is that I'd be happy for the dyno to show 150kW if it ran 140mph! :)

From what I've seen, 120mph with 260-270rwkw is right on the money. My numbers below were achieved at that power level.

From what I've seen, 120mph with 260-270rwkw is right on the money. My numbers below were achieved at that power level.

Not disputing that for a second. It's just people get so caught up with dyno figures it blows me away.

Found this link while doing some more research. Okay, I'll admit it, you guys planted enough of a seed to start my brain racing. Bastards!!

Aussie Ethanol

They list the Barrack Heights Ethanol service station as selling the stuff too. And the best bit? It's 2 mins drive from my house.

You bastards!

That is all.

You bastards.

Waiting for the final word from my tuner but yes, it's looking that way. I think the thing that sealed the deal was the servo so close to me and the fact that I'll give it a go, decide if it's worth the farting around and then go from there.

Adelaide had a shortage of E85 for a few weeks and i had to use varied blends of premium mixed with E85 and i was suprised how little E85 was needed to prevent knocking!! so i wouldnt stress too much if it's not 100% consistant, only downside i could see was a higher consumption!

Edited by 180or200

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