Yet another E-85 thread.

T. Bix

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I know some of this has been covered but there isn't enough to put it all together. So I have been trying to figure out an easy way to switch my new build over to E-85 without the use of a bunch of dyno time. Lets just say for now I'm starting out with a stock motor with a stock mapped ECU just flashing the limiters higher. Much in the way a FMU works to increase the fuel flow by increasing the fuel pressure through whatever injectors you are using, Can I with the use of an external pump/regulator just jack up the pressure 30% to get it in the ball park? I've never measured stock pump output but for some reason I have it in my head that it should be 42 PSI. This means I can increase the pressure to 54.5 PSI and get 30% increase in fuel flow.... I think.. At least if I have a starting point I can use the WEGO to guide my fine tuning... I Think...

Anybody have any thoughts?
 
I have run E85 in my drag bike now for 3 years 2 of which were with a non flashed ECU. BIke was never cosistant and the fuel tables were extremely high, alot of timing as well as fuel pressure dyno tuned Flashed the ECU to balance the injectors and re tuned the bike on the dyno bigger HP and torque numbers bike is consistant in the mid 8's
 
Higher pressure should push more fuel. But there will eventually be a maximum amount it will flow regardless of pressure. Anything above that just ends up in damage and parts breaking
That said I do not know what the increase of pressure to increase in fuel flow ratio will be.
 
I’ve done one high compresseion 1441, and just last week tuned a stock motor stage 1 gen 2 on e98.

For some reason the 30% rule goes out the window on hayabusas. And just the same as the rumor of poor fuel mileage on e85.

Both bikes run stock fuel pressure. Both bikes also only needed about 12% more fuel added to most the table and 15-18% in the 75% and up parts of the table.

I will also say, both bikes only liked about 5* timing more added to the table BELOW 75% throttle. Adding timing after peak torque netted zero gains. The all motor bike actually picked up more hp with less timing after peak torque.

This is very interesting data as with any car I’ve switched over to ethanol fuel always wanted 7-10* more timing, and usually even more in the 75% and up part of the map.

What this tells me in the assumed well designed combustion chambers and/or cams are actually not as efficient as everyone would like to think. I’ll be doing more testing with these fuels very soon on the shop bike.
 
Interesting. Do you think a port and polish would give it a cleaner burn and better uumph or is it perhaps an over all design issue in the entire intake system
 
Well that is a bit of a surprise to me. With everything else they do for power I would have thought that was automatic. Good to know. Thank you.
 
This is very interesting data as with any car I’ve switched over to ethanol fuel always wanted 7-10* more timing, and usually even more in the 75% and up part of the map.

What this tells me in the assumed well designed combustion chambers and/or cams are actually not as efficient as everyone would like to think. I’ll be doing more testing with these fuels very soon on the shop bike.

I've always thought that the more efficient the chamber/port combination the less timing was required to convert the chemical power in the fuel into mechanical energy... For instance the newer "cathedral port" chevy motors need less timing to make the same power as the old small blocks for a given engine size w/similar mods. This is anecdotal but something that I've seen demonstrated and assumed it was design architecture....

Boosted, can you add some thoughts on this?
 
I've always thought that the more efficient the chamber/port combination the less timing was required to convert the chemical power in the fuel into mechanical energy... For instance the newer "cathedral port" chevy motors need less timing to make the same power as the old small blocks for a given engine size w/similar mods. This is anecdotal but something that I've seen demonstrated and assumed it was design architecture....

Boosted, can you add some thoughts on this?

No, you’re absolutely correct, perhaps my wording wasn’t as clear as it should of.

I’m fluent in the LS platform. The cathedral, ls3, and ls9 stuff is all identical. It doesn’t just apply to cathedral heads.

When you get in to aftermarket heads you’ll hear the term “fast burn”. That means the combustion chambers are way more efficient. You’ll also find that they take significantly less timing the the conventional head that it’s modeled off of.

Had a buddies conventional headed BBC with twin 88’s on my dyno awhile back. 25psi, and over 30* of timing before we started seeing diminishing gains. Try that on an ls engine and you’ll be picking pistons out of the oil pan.

My 4.8 80mm fox.
2DFBF7FF-E3D8-4B59-9A45-C29CA06191C0.jpeg
 
What kind of hp increase did you get on the NA 1441?
My 1340 Gen II made 221 on MR12 but I've bumped the CR up for this latest build and a) think the CR is too high for MR12 b) would like to know if it is worth going to E98 or stick with VP C45 for the tune.
Thanks
 
What kind of hp increase did you get on the NA 1441?
My 1340 Gen II made 221 on MR12 but I've bumped the CR up for this latest build and a) think the CR is too high for MR12 b) would like to know if it is worth going to E98 or stick with VP C45 for the tune.
Thanks

It picked up 15hp going from c16 to ignite e85. Then another 12hp going to vp c85.

We changed a few things in the engine and then tuned it on Sunoco e85. This weekend gonna give it a try on e98 as well.
 
No, you’re absolutely correct, perhaps my wording wasn’t as clear as it should of.

I’m fluent in the LS platform. The cathedral, ls3, and ls9 stuff is all identical. It doesn’t just apply to cathedral heads.

When you get in to aftermarket heads you’ll hear the term “fast burn”. That means the combustion chambers are way more efficient. You’ll also find that they take significantly less timing the the conventional head that it’s modeled off of.

So I guess my real question was that based on experience on the dyno, where do we fall in the combustion/cylinder filling, intake tract efficiency? And if we are lower on the scale so to speak, What can we do to fix it? I was under the impression that our engine architecture was fairly efficient. For a N/A motor this may not be the case. I believed this until I found myself in a conversation with an LS engine builder. I guess the real answer was a shocker to me and can maybe be found in the ignition maps required to find our peaks.... I dunno just some thoughts... Please share if you have some..
 
So I guess my real question was that based on experience on the dyno, where do we fall in the combustion/cylinder filling, intake tract efficiency? And if we are lower on the scale so to speak, What can we do to fix it? I was under the impression that our engine architecture was fairly efficient. For a N/A motor this may not be the case. I believed this until I found myself in a conversation with an LS engine builder. I guess the real answer was a shocker to me and can maybe be found in the ignition maps required to find our peaks.... I dunno just some thoughts... Please share if you have some..

The engine as a whole is very efficient. My comments on combustion chamber efficiency was speculation. Move inline engines take a bunch more timing the v or flat engines purely off their specific design principles.

As far as cylinder filling I’m guessing you’re talking about the harmonics or pulse waves you hear guys in the ls world talk about. That’s also why many intakes have interchangeable runners to get the pulse to hit the intake valves right as they open. I really don’t have any idea how efficient the bikes are in regards to this. They don’t have an actual intake manifold, and I’d imagine ITB’s effect that whole concept differently? I just don’t have an answer for that.

How can we make it better? A completely aftermarket head would be key. But it’s such a nitch market I don’t see anyone spending the time and money to make an aftermarket head.

I’ll leave off with this. I tuned that high compression 1441 on x98. Picked up 11whp over Sunoco e85r.

I also tuned my bone stock 08 Busa on x98. It picked up 6hp and 4tq across the entire rpm range. Not bad. It made the same as pump gas until I put 1 degree of timing in it, that’s where the difference came from across the board. Put one more in and only picked up 2hp after that, so I backed it back down. It still has the stock header with cats. But I’d imagine with an aftermarket header or at least cats removed I’d bet it would like a bit more timing. Fighting back pressure at that point. The bike also needed a 40% increase in fueling on the wot table which is vastly different then the other bikes I talked about in this thread. Interesting stuff.
 
No, you’re absolutely correct, perhaps my wording wasn’t as clear as it should of.

I’m fluent in the LS platform. The cathedral, ls3, and ls9 stuff is all identical. It doesn’t just apply to cathedral heads.

When you get in to aftermarket heads you’ll hear the term “fast burn”. That means the combustion chambers are way more efficient. You’ll also find that they take significantly less timing the the conventional head that it’s modeled off of.

Had a buddies conventional headed BBC with twin 88’s on my dyno awhile back. 25psi, and over 30* of timing before we started seeing diminishing gains. Try that on an ls engine and you’ll be picking pistons out of the oil pan.

My 4.8 80mm fox.
View attachment 1590906
Hi. My friend has a BBC 572 with twin 108s it makes around 3400 HP He just went with a new auto trans set up.
 
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