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Discussion Starter #1
Sup guys, new to the forum. I'm in the process of putting my setup back together after it broke a rod and I was considering using e85 since it's so plentiful in my area but I didn't know if I was wasting my time since I'm using a stock bottom end. Here's the rundown:

D16z6, engine rebuilt with all OEM Honda parts
ARP head studs
Blox cam, upgraded valve springs and retainers
Blox intake manifold
Custom ramhorn tubular manifold
T3/t04e 50 trim
Full 3 inch exhaust
RC 750s with Walbro 255
Hondata

Obviously I would upgrade the fuel components but with the bottom end being stock I didn't know if I should even waste my time. Let me know what you thonk
 

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e85 actually might be better since you have a stock bottom end. e85 will resit dentition a lot better and is cooler burning. Those RC's might not like it though
 

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Discussion Starter #5
e85 actually might be better since you have a stock bottom end. e85 will resit dentition a lot better and is cooler burning. Those RC's might not like it though
The only thing I was worried about was the extra torque I would make and the increased cylinder pressure killing the stock rods. I plan on building a motor once I get this one running but I'd still like to have some fun first lol
 

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Ran RC 440's for four years daily on E85 running 14-20PSI on a GReddy kit.

Stock D15Z1 block / D16Z6 head. Just ARP headstuds.

You'll be fine.
 

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I don't think I understand. Bottom end will handle no more than 220 hp before a rod is bent/broken. E85 is to resist detonation as said above to run more boost/timing. I see absolutely NO reason to convert because your stock block will crap out way before you will put that e85 to use. Just keep it 93 until you decide to build your block.
 

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I don't think I understand. Bottom end will handle no more than 220 hp before a rod is bent/broken. E85 is to resist detonation as said above to run more boost/timing. I see absolutely NO reason to convert because your stock block will crap out way before you will put that e85 to use. Just keep it 93 until you decide to build your block.
You are Wrong.
 

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TheToaster please explain to me why e85 would be useful at his power level? I'm honestly just curious as I always thought the only use was because of detonation resistance to make more power
 

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TheToaster please explain to me why e85 would be useful at his power level? I'm honestly just curious as I always thought the only use was because of detonation resistance to make more power
I'll explain it to you. The reason a motor bends or breaks a rod is due to detonation. If you eliminate it with a quality fuel your motor will handle more power.
 

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I'll explain it to you. The reason a motor bends or breaks a rod is due to detonation. If you eliminate it with a quality fuel your motor will handle more power.
If detonation is the issue, then why not just properly tune the engine for 93? (this is a rhetorical question)

E85 has it's benefits, but they could be a double edged sword. E85 has a faster flame front than gasoline, and is more resistant to detonation. So what would happen if you advanced ignition timing and increased cylinder pressure, even if you weren't seeing detonation? Think you might bend a rod? The stock rods can only take so much stress, using a different fuel isn't going to change that.

Though applying the stress differently might allow for some leeway.
 

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I just thought that where our stock rods are toothpicks that it doesnt matter what fuel you use, you will still max out at the low 200s before a rod bends. Yes I know that heat is what kills engines, but damn those rods are already the weak link in our motors. I just can't comprehend why 250 whp on e85 is any more reliable than 250 on 93..
 

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Because the fuel is more efficient. You will make more power with less boost, therefore creating less stress on the internals. For example. I watched power block TV where they built a 350 engine and Dyno tuned it on 93 pump. They then only changed the jets on the carb and made a run and gained over 50 hp without changing anything else. After some tuning, they netted 89 hp over the 93 fuel. I have read threads of people switching with d series and made more power on less boost pressure. So if you can make 250 whp on 12 lbs with 91, you may make 250 whp on 10 lbs on e85, thus creating less stress on the internals of the engine. How efficient the fuel is to make the power has everything to do with how hard it is on your engine.
 

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Sup guys, new to the forum. I'm in the process of putting my setup back together after it broke a rod and I was considering using e85 since it's so plentiful in my area but I didn't know if I was wasting my time since I'm using a stock bottom end. Here's the rundown:

D16z6, engine rebuilt with all OEM Honda parts
ARP head studs
Blox cam, upgraded valve springs and retainers NO
Blox intake manifold NO
Custom ramhorn tubular manifold
T3/t04e 50 trim
Full 3 inch exhaust
RC 750s with Walbro 255 Hiprofile injectors are better and from this century no lasts
Hondata

Obviously I would upgrade the fuel components but with the bottom end being stock I didn't know if I should even waste my time. Let me know what you thonk
Ring lands will break before the rods bend. Open up the rings to .018 top, .019 second, and leave the oil control rings un touched.

FYI epic tuning had a oem z6 making north of 400hp for over a year before it bent all 4 rods. The kept the revs low and open up the rings.
 

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Why not just wait until you find an additional $500 to build the bottom end correctly so you won't have to worry about it?
 

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I'll explain it to you. The reason a motor bends or breaks a rod is due to detonation. If you eliminate it with a quality fuel your motor will handle more power.
This. E85 has more tolerance for error. If you have 2 identical stock engines running the exact same setup and making the same power, the e85 will be safer to daily than the 92-93 octane one.

In addition faster flame travel means you can get the same combustion peak pressure in less time, which means you can give it less timing to peak the combustion event at the same point in engine rotation. This means there is less pressure building over the time the rod/crank is at a poor angle before/right after TDC and less stress on things like the rod and ring lands.

In the end, if you are ok with the cost and e85 is easily available, I would definitely run it over 93 octane any day of the week in a FI car.
 

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Because the fuel is more efficient.
E85 is not more efficient than gasoline. If it were, then you wouldn't need to use more of it to make the same power as would with gasoline. Perhaps "efficient" wasn't the word you were looking for.

E85 has more tolerance for error.
This is true, and the cooler burn doesn't hurt either.

If you have 2 identical stock engines running the exact same setup and making the same power, the e85 will be safer to daily than the 92-93 octane one.
The connecting rod has a specific tensile strength, exceed it and bad things happen. Though how and when this pressure is applied make a difference.

In addition faster flame travel means you can get the same combustion peak pressure in less time, which means you can give it less timing to peak the combustion event at the same point in engine rotation.
This sounds good in theory, but all the E85 cars I have worked on needed wanted more timing to make power. So does the it really change when that pressure is applied?

You are going to need to do a lot of math to figure this out.

Take a look at this.
http://dspace.mit.edu/bitstream/handle/1721.1/59952/676953430.pdf
There is a section that talks about cylinder pressure. The graph for gasoline and e85 are very similar, but E85 needed to be fired at 18* BTDC to make the same force as gasoline at 10.5*.


This means there is less pressure building over the time the rod/crank is at a poor angle before/right after TDC and less stress on things like the rod and ring lands.
I can see where this would be true, but in real world tuning on the dyno I have found E85 likes more advance. See above.

turboprelude95 is correct. It's a combination of the parts and the tune. You can make more power than most think you can on a stock bottom end (with either fuel), but it comes at a cost. Fatigue, and over time that will come back to bite you in the ass.
 

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Discussion Starter #20
Why not just wait until you find an additional $500 to build the bottom end correctly so you won't have to worry about it?
In a bit of a rush to put the car together and I don't have time to wait on getting the engine built. Just gonna get it tuned on the setup I have now using e85 and then build a motor and add ID1000 and a Walbro e85 pump in the next few months.

I'll post results when I get it together. The car is getting painted and parts are getting powder coated right now so should be within the next 2 weeks
 
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