Tuning with E85

[Chicken Patty]

So a little update on my tuning.

I kept getting some knock from about 4.5k to redline. It's hard to knock on E85 and my car hasn't shown any sign of deterioration or hasn't blown or anything. So I'm pretty sure it was not real knock.


So I finally fixed all boost leaks, and got ready to fiddle with it. So I go and again the same thing, WTF.

Well, I came across a sick deal on a C.O.P. Setup and now my knock is gone. WTF? Does this sound right? Perhaps bad spark causing improper burn or something? This would mean it's not false knock then? Any ideas?

 

[forcefed86]

So a little update on my tuning.

I kept getting some knock from about 4.5k to redline. It's hard to knock on E85 and my car hasn't shown any sign of deterioration or hasn't blown or anything. So I'm pretty sure it was not real knock.


So I finally fixed all boost leaks, and got ready to fiddle with it. So I go and again the same thing, WTF.

Well, I came across a sick deal on a C.O.P. Setup and now my knock is gone. WTF? Does this sound right? Perhaps bad spark causing improper burn or something? This would mean it's not false knock then? Any ideas?

Shouldn't be related. It all goes back to reading the plugs. If they have speckles on them, it wasnt PK. If they look great is was PK. What were the plugs gapped at? You should be able to open up the plugs a ton with a good COP setup.

 

[Chicken Patty]

Shouldn't be related. It all goes back to reading the plugs. If they have speckles on them, it wasnt PK. If they look great is was PK. What were the plugs gapped at? You should be able to open up the plugs a ton with a good COP setup.

I am running BR8ES at .020" now, should I open it up?

This knock issue persisted with BR7's and even the BR8's at .025". But I closed them to see if it made any difference as I was just about ready to try anything.

Also, the plugs look like new, very clean burn, no speckles.

 

[forcefed86]

May get a tiny bit more power opening them up. I'd keep opening them up until you get a miss, then back down a hair. I've see pople run 40+ gaps with COP setups on boosted ls1's. Bigger gap = bigger spark and better flame front. Just depends how much output the coils provide.

 

[Chicken Patty]

May get a tiny bit more power opening them up. I'd keep opening them up until you get a miss, then back down a hair. I've see pople run 40+ gaps with COP setups on boosted ls1's. Bigger gap = bigger spark and better flame front. Just depends how much output the coils provide.

I'm running the 300M coils, heard they are pretty good. Gonna try and run them back at .025" which is what I see most people run. Then go from there. Thanks for the info.

 

[eclipsegst1990]

So a little update on my tuning.

I kept getting some knock from about 4.5k to redline. It's hard to knock on E85 and my car hasn't shown any sign of deterioration or hasn't blown or anything. So I'm pretty sure it was not real knock.


So I finally fixed all boost leaks, and got ready to fiddle with it. So I go and again the same thing, WTF.

Well, I came across a sick deal on a C.O.P. Setup and now my knock is gone. WTF? Does this sound right? Perhaps bad spark causing improper burn or something? This would mean it's not false knock then? Any ideas?

Please make sure your knock sensor is torqued properly. Mine was too tight and picking up everything as knock in the 3.5 to 4.5 range. 17 to 20 ft/lbs. i believe. I was battling this phantom knock for years and always having timing pulled by the computer until this simple fix cured it.

 

[Chicken Patty]

Please make sure your knock sensor is torqued properly. Mine was too tight and picking up everything as knock in the 3.5 to 4.5 range. 17 to 20 ft/lbs. i believe. I was battling this phantom knock for years and always having timing pulled by the computer until this simple fix cured it.

I don't check because what torque wrench can you fit back there? Any in particular that you used?

 

[forcefed86]

I don't check because what torque wrench can you fit back there? Any in particular that you used?

Put a dab of med locktite on it and hand tighten, then go 1/4 turn.

 

[Calan]

And make sure it is in the correct location. There are two holes that are pretty close to each other that it will screw into.

 

[Chicken Patty]

I'll try to check tomorrow and let you know. Thanks guys.

 

[eclipsegst1990]

A crows foot works nicely and if you're one of those rocket scientists that likes the perfect torque, then this is what I've done in the past. It is a PITA.

Torque Wrench Adapter Calculator - CNCexpo.com

 

[gofer]

Here's a bit more info on torquing the knock sensor with a crows foot. Knock Sensor Torque With A Crows Foot

 

[Chicken Patty]

Thanks for the info guys, I'll have to check local stores, see if they have anything like it.

 

[Chicken Patty]

Question guys. When you tune for MBT, where are you supposed to The gain in power? Peak power only or everywhere you added timing?

Also, each degree should be about 7-10whp, right?

 

[Chicken Patty]

Anybody wanna chime in on the above question? Also, is there a particular way you dial in your peak torque timing?

 

[Calan]

The only really accurate way to do it is on a load dyno, where you can sweep the timing at every breakpoint in the RPM and load maps under steady state conditions (research "spark-hook test"). For any given operating condition, you'll get to a point where torque will no longer increase linearly with an increase in ignition timing. At that point, you are within a couple of degrees of MBT which is ideal.

The exceptions to that are points at higher loads where you become knock-limited, and at idle/low load conditions where you want to run less than MBT to maintain a torque reserve for sudden changes in engine demand (power steering, a/c, etc).

 

[Chicken Patty]

The only really accurate way to do it is on a load dyno, where you can sweep the timing at every breakpoint in the RPM and load maps under steady state conditions (research "spark-hook test"). For any given operating condition, you'll get to a point where torque will no longer increase linearly with an increase in ignition timing. At that point, you are within a couple of degrees of MBT which is ideal.

The exceptions to that are points at higher loads where you become knock-limited, and at idle/low load conditions where you want to run less than MBT to maintain a torque reserve for sudden changes in engine demand (power steering, a/c, etc).

You lost me there. Since I don't know of any load dyno's in the area, how would it work on just a regular dynojet per say?

I know poeple say to run low timing before peak torque I just don't know how low of timing I need to run . It's the only part of E85 tuning I am not clear off.

 

[project_skyline]

You ALWAYS ALWAYS ALWAYS run a colder plug on E85 then what you were with 91-93 octane or else you'll get pre-ignition. Stock DSM's typically run a BRP6ES plugs gapped to .026", modified on pump I recommend NGK BRP7ES plugs gapped to .028", and on E85 I recommend NGK BR8ES (No "P" in the part number) plugs gapped to .025".

E85 is highly resistant to knock but susceptible to whats called fuel pre-ignition, this is why you see tuners running E85 and melting pistons, valves, and spark plugs without ever seeing 1* of knock when it happens.

Quoted from NGK:

I'll second that! The only reason to run a warmer plug is if you are fouling your current plug. Hot plugs are for petrol cars. I'm also partial to not running a projected plug in turbo cars. (many have no problems doing so)

I run a br9es and I have NO plug fouling. There is no reason to run a hot plug on a turbo/e85 car. I also ran my plugs right out of the box. Gapped at .030 (maybe .028 didn't check). This is on top of water/meth injection (washer fluid). Even with the added water in the combustion mixture I have no spark "blow out" at 35+ psi. Factory IGN parts, cheapo autozone wires.

That's interesting because I've found in all instances that colder plugs on e85 do absolutely nothing. More big name tuners then I know also see the same thing.

I would advise the completely opposite. Colder plugs for pump gas/some race fuels and stock heat range or hotter plugs (depending on application) for e85. Fouling plugs can have absolutely nothing to do with what heat range your using.

Ethanol burns cooler then gasoline therefore no reason to run plugs as such. Cooler for cooler and hotter for hotter.

But if that's what you guys want to think everyone is entitled to their opinion.

 

[98GSXtacy]

That's interesting because I've found in all instances that colder plugs on e85 do absolutely nothing. More big name tuners then I know also see the same thing.

I would advise the completely opposite. Colder plugs for pump gas/some race fuels and stock heat range or hotter plugs (depending on application) for e85. Fouling plugs can have absolutely nothing to do with what heat range your using.

Ethanol burns cooler then gasoline therefore no reason to run plugs as such. Cooler for cooler and hotter for hotter.

But if that's what you guys want to think everyone is entitled to their opinion.

Hey Will, it's Jeff from RCM, I think one of the main things with the heat range of plugs is location. After reading this entire thread, I have noticed that most users that are using colder plugs live in areas that are normally high heat and/or high humidity, not to mention, air that is much more dense. I think that with our location being thinner, cooler, and often dryer air, we may experience the opposite sort of affect when it comes to plug heat ranges, especially with e85.

Not sure if I am right here but it makes sense to me as a logical explanation. Nice to see you on tuners by the way.

 

[donniekak]

That's interesting because I've found in all instances that colder plugs on e85 do absolutely nothing. More big name tuners then I know also see the same thing.

I would advise the completely opposite. Colder plugs for pump gas/some race fuels and stock heat range or hotter plugs (depending on application) for e85. Fouling plugs can have absolutely nothing to do with what heat range your using.

Ethanol burns cooler then gasoline therefore no reason to run plugs as such. Cooler for cooler and hotter for hotter.

But if that's what you guys want to think everyone is entitled to their opinion.

Although ethanol is less detonation prone than gasoline, it is more prone to preignition. A colder, non projected plug helps prevent this.