How much timing are you running E85 users??

[JayRolla]

Went out with my brother and helped him tune his e85 16g powered car. Has all supporting mods including 1000cc injectors, 272 cams, fmic, ect... Now the car is running 28psi dropping to about 24psi by 7000rpm's, which we hopefully are fixing with a 38mm WG.

We started adding timing, we are at about 24* by redline and the car just will not knock. No madder what I add we get maybe three spots where 1 count of knock shows up and that is it.

How much timing is safe of cast stock oem internals. If the tune is good and there is no detenation could we add some more or should we leave where its at.

Also let me know what you e85 guys are running. From what Ive researched a lot of people run way more aggressive timing on e85 than even with c16 gas.

 

[JeffGST]

E85 is amazing stuff, isn't it?

Increasing timing does not increase WHP in a linear fashion. I experienced a 9 WHP gain going from 15 to 16 degrees and another 9 WHP from 16 up to 17. The problem is that once you get past 20 degrees the gains diminish.

Anything higher than 23 degrees of advance will not increase VE greatly. It's not worth the 1 or 2 extra WHP gain to increase timing any more than that. All you end up doing is reducing your margin of error to almost nothing when running timing that high.

I have datalogs 1/4mi passes of 33 PSI and 23 degrees of timing with no knock. E85 is so knock resistant that it acts like a race fuel. The problem is that you can introduce extremely high cylinder pressures before the knock sensor hears an issue.

That night I ran 10.7, 10.7 and 10.8, all at 134-136 MPH trap speeds. But on that last 10.8 pass, I cracked the block from the insane timing curve I was running. There was no knock, but the extreme pressures of 33 PSI and 24-25 degrees finished off the block. There were MANY other factors that caused my block to crack (rust cavitation) but the high timing did not help.

33 PSI boost pressure with 25 degrees of timing creates MUCH HIGHER COMBUSTION PRESSURES than 36 PSI boost pressure with only 15 degrees of timing. I currently run E85 and limit my timing to only 20 degrees even though I still have no sign of knock.

The moral of the story is...

MAKE MORE POWER WITH BOOST and not timing. Timing increases VE with an efficient burn but reduces margin of error.

 

[JayRolla]

That makes a lot of sense. Its between 22-24* right now so we will keep it there. The car is making great power but the boost is dropping off way too much, I guess we just need to fix that problem.

 

[slowgsr]

If i were you i would get it on the dyno and tune for your MBT.

 

[JayRolla]

If i were you i would get it on the dyno and tune for your MBT.

Ahh we dont really believe in wasting money on dyno's, if we where going to tune like that we would hit the track, that gives you real numbers.

 

[JeffGST]

Ahh we dont really believe in wasting money on dyno's, if we where going to tune like that we would hit the track, that gives you real numbers.

The Trap Speed Dyno! The only one that counts!

 

[2gGSX]

Unfortunately, you can't really tune for MBT on the track since it's not a controlled environment. The dyno gives you repeatability, where the only thing being changed (conceivably) is timing.

 

[SpeedAddict62]

I'm not sure how timing affects VE (volumetric efficiency) at all (it affects BSFC, not VE), but I do agree with everything else. Nothing is to be gained by going above MBT. If you aren't pushing the limits, running more boost will probably gain you more power than another few degrees of timing.

 

[desolateboosted]

Wow, seems like we've come to the days where running high timing on "pump fuel" is now not an issue. Except if you want to blow a HG or crack a block

 

[slowgsr]

Timing has nothing to do with VE.

Have fun tuning for MBT at the track, with all that money you will be saving without having to pay for dyno time, you can spend it on a new motor when you destroy yours, until you get your trial and ERROR methods worked out.

Running more boost will increase VE obviously, providing your turbo has sufficient airflow, adding timing will not increase VE of an engine. Valve timing drastically effects the VE, not the ignition timing.

I don't want to get into what I know about spark advance, because it is very little, but obviously more then is in the above posts, and i would never tune a car or consider myself anywhere close to having the required skills to tune a car.

However, spark advanced is designed to produce peak torque by burning the mixture at peak cylinder pressures.. more timing provides higher cylinder pressures, and a greater chance for detonation and engine failure to occur... but so many things effect timing values, like engine speed (the faster an engine turns the spark plug must fire at an earlier crank position to allow time for a given air/fuel mixture to ignite and achieve a high burn rate and maximum cylinder pressure by the time the piston is positioned to produce best torque)... and AFR's, the denser (richer) the mixture burns faster.. mixture flame speed is also important which is based on the type of fuel and operating conditions...

I cant begin to understand WHY people ask for timing values on here.. As to say if engine X is the same as engine Y etc.. EVERY engine requires different timing values, because EVERY engine has different VE tables.

However, i would keep your timing under 20, but again.. every setup is different, take my knowledge for what its worth, what its worth is your call. You don't feel a dyno is a essential tuning tool for any setup, then risk your setup tuning trial and error method on the street, which is what you feel comfortable doing.

A general idea about octane value, for every degree of timing past 15deg ATDC, your cylinder pressures will increase to the effect a octane requirement of 0.5 to 0.75 to shy away any signs of detonation, again this is just an estimate.

I don't believe E85 makes can make more power then C16, c16 resists detonation more then E85 due to its higher octane level, so i don't see how people can run more spark advance with E85 than C16, it dosen't fit theory, maybe there just all too cocky, much like yourself.

So in regards to your original post, with no detonation i wouldn't go any higher then 20-21 deg of spark advance, once you go past, start worrying about cylinder pressures alone destroying your engine, at the boost pressures noted anyways.

High cylinder pressures cause detonation, not strictly high timing values, its a combination of boost pressures + spark advance which will increase cylinder pressures and increase the risk of detonation.

Increasing the engines VE is what will make most of the power, what im trying to get you to understand, to make more power, you run more boost, and decrease timing thus giving your normal cylinder pressures, the higher cylinder pressures can increase power if there is no detonation and the engine can handle the stress..

Goodluck.

I still say you need to put this thing on a dyno and have it tuned by a professional if you want it to last, and run to its full potential which with the knowledge you demonstrate are incapable of doing, again.. unless this setup is just strictly trial and error for yourself to get better in tuning. Theory should always come before practice.

 

[JayRolla]

Timing has nothing to do with VE.

Have fun tuning for MBT at the track, with all that money you will be saving without having to pay for dyno time, you can spend it on a new motor when you destroy yours, until you get your trial and ERROR methods worked out.

Running more boost will increase VE obviously, providing your turbo has sufficient airflow, adding timing will not increase VE of an engine. Valve timing drastically effects the VE, not the ignition timing.

I don't want to get into what I know about spark advance, because it is very little, but obviously more then is in the above posts, and i would never tune a car or consider myself anywhere close to having the required skills to tune a car.

However, spark advanced is designed to produce peak torque by burning the mixture at peak cylinder pressures.. more timing provides higher cylinder pressures, and a greater chance for detonation and engine failure to occur... but so many things effect timing values, like engine speed (the faster an engine turns the spark plug must fire at an earlier crank position to allow time for a given air/fuel mixture to ignite and achieve a high burn rate and maximum cylinder pressure by the time the piston is positioned to produce best torque)... and AFR's, the denser (richer) the mixture burns faster.. mixture flame speed is also important which is based on the type of fuel and operating conditions...

I cant begin to understand WHY people ask for timing values on here.. As to say if engine X is the same as engine Y etc.. EVERY engine requires different timing values, because EVERY engine has different VE tables.

However, i would keep your timing under 20, but again.. every setup is different, take my knowledge for what its worth, what its worth is your call. You don't feel a dyno is a essential tuning tool for any setup, then risk your setup tuning trial and error method on the street, which is what you feel comfortable doing.

A general idea about octane value, for every degree of timing past 15deg ATDC, your cylinder pressures will increase to the effect a octane requirement of 0.5 to 0.75 to shy away any signs of detonation, again this is just an estimate.

I don't believe E85 makes can make more power then C16, c16 resists detonation more then E85 due to its higher octane level, so i don't see how people can run more spark advance with E85 than C16, it dosen't fit theory, maybe there just all too cocky, much like yourself.

So in regards to your original post, with no detonation i wouldn't go any higher then 20-21 deg of spark advance, once you go past, start worrying about cylinder pressures alone destroying your engine, at the boost pressures noted anyways.

High cylinder pressures cause detonation, not strictly high timing values, its a combination of boost pressures + spark advance which will increase cylinder pressures and increase the risk of detonation.

Increasing the engines VE is what will make most of the power, what im trying to get you to understand, to make more power, you run more boost, and decrease timing thus giving your normal cylinder pressures, the higher cylinder pressures can increase power if there is no detonation and the engine can handle the stress..

Goodluck.

I still say you need to put this thing on a dyno and have it tuned by a professional if you want it to last, and run to its full potential which with the knowledge you demonstrate are incapable of doing, again.. unless this setup is just strictly trial and error for yourself to get better in tuning. Theory should always come before practice.

Funny that you say I'm cocky when you look to be the cocky one. E85 seems to fight detonation way better than its rating of 100-105 octane. I know people that have made more power on e85 than there c16 tunes and live only by e85 now.

The car is being tuned by a professional. He said to run it around 22-26* which we are at. I wanted to know if a few degrees more would be worth adding instead of paying money to have someone add a little timing or remove some at a shop. The car is at a perfect afr and I dont think any other tuner would even change it so it would be a waste of money in my opinion.

Boost is at the highest level the 16g can handle and car is running great. The motor is the original motor since 1990 and has been tuned at 20+ psi on pump for over 7 years and has never seen a dyno so we know what we are doing. Still has good compression and near 200,000 miles. Dynos are not needed for tuning when you have the right tools. It may net a little more tq, but its not going to do much.

 

[slowgsr]

Funny that you say I'm cocky when you look to be the cocky one. E85 seems to fight detonation way better than its rating of 100-105 octane. I know people that have made more power on e85 than there c16 tunes and live only by e85 now.

The car is being tuned by a professional. He said to run it around 22-26* which we are at. I wanted to know if a few degrees more would be worth adding instead of paying money to have someone add a little timing or remove some at a shop. The car is at a perfect afr and I dont think any other tuner would even change it so it would be a waste of money in my opinion.

Boost is at the highest level the 16g can handle and car is running great. The motor is the original motor since 1990 and has been tuned at 20+ psi on pump for over 7 years and has never seen a dyno so we know what we are doing. Still has good compression and near 200,000 miles. Dynos are not needed for tuning when you have the right tools. It may net a little more tq, but its not going to do much.

Your right, e85 is far superior to c16 and is the new way of the future, your right cars that never see dyno's are often the cars tuned properly to their highest potential. A dyno is not a essential tool for tuning, as long as you have all the right tools, and its a great idea to push a 200k + motor to the cylinder pressures im sure your engine is seeing, great idea which i could do that.

I guess that is what you wanted to hear? Goodluck.

 

[slowgsr]

As far as a professional tuner doing your work and recommending timing values between 22-26 deg.. i find this bogus and ANY tuner.. that will tune a car to any degree without a dyno, i wouldn't consider a professional. Professional tuners tune cars on dyno's, and typically have one in house to use. Not to mention the difference between 22 and 26 degrees, i wouldn't trust this guy with my lawnmower... This is a near exact science, not just rough numbers, anywhere from 11:1 to 13:1 AFR's should be alright i guess?

Street tuning cars doing countless 4th gear pulls is very dangerous, very stupid also. I despite people who do this kind of thing, a professional tuner as you say who tuned your car, would never do any sort of in depth tuning without a dyno. Typically the only street tuning done is to verify a dyno tune.

You need to understand a dyno is vital to get a proper tune on any vehicle. I dont understand HOW you can argue that you can tune a vehicle properly without the use of a dyno? The dyno environment is #1 reason, and the ability to view increase or decrease in power figures, the actual numbers aren't as important.

 

[desolateboosted]

I believe the reason why e85 resists knock so well is because not only is it 105 octane, you also have to throw about 30% more fuel into the combustion chambers thus additional cooling is applied by the fuel allowing the engine to resist knock heavily.

Back with pump gas if you wanted to resist knock, you'd have to add more fuel to richen it up or decrease timing.

Now with e85 ratios @ WOT, e85 ratios scale way lower than any pump gas ratio. The additional cooling from the fuel is there + better octane rating = great gas.

 

[Joesmoke]

To the OP:

Go ahead and ramp up timing on that E85 until the power drops off, or it knocks. Most people never advance timing (or cant) when they switch to high octane SLOW BURN fuels. Race gas, e85 etc. Most dont have the cajones to play with timing and miss a lot of opportunity..

Ive continued to make power with timing above 24 deg and high boost while injecting methanol. Same premise as running on e85 (introducing a slow burn fuel)

Good luck and happy calibrating!

 

[biglady112]

I am with Jeff. High boost low timing. My pump gas maps don't look all that different than E85 maps. It took me a long time, but after Jeff went through his second block last year, he finally started to come around. Now he makes power much easier and the car has been more or less reliable motor wise. Drivetrain is another issue though.

Steven

 

[JayRolla]

Jeff said he got about 10whp just from going 15-16*, thats a huge increase in my eyes. Also what about the tq, doesnt the timing effect tq more than hp. I guess we will keep it at 22* right now. When we hit the track we will add timing and see how it effects the trap speeds.

 

[JayRolla]

As far as a professional tuner doing your work and recommending timing values between 22-26 deg.. i find this bogus and ANY tuner.. that will tune a car to any degree without a dyno, i wouldn't consider a professional. Professional tuners tune cars on dyno's, and typically have one in house to use. Not to mention the difference between 22 and 26 degrees, i wouldn't trust this guy with my lawnmower... This is a near exact science, not just rough numbers, anywhere from 11:1 to 13:1 AFR's should be alright i guess?

Street tuning cars doing countless 4th gear pulls is very dangerous, very stupid also. I despite people who do this kind of thing, a professional tuner as you say who tuned your car, would never do any sort of in depth tuning without a dyno. Typically the only street tuning done is to verify a dyno tune.

You need to understand a dyno is vital to get a proper tune on any vehicle. I dont understand HOW you can argue that you can tune a vehicle properly without the use of a dyno? The dyno environment is #1 reason, and the ability to view increase or decrease in power figures, the actual numbers aren't as important.

Im not trying to be cocky man. We are street tuning and most likely wont hit the dyno. The car feels awesome at this timing. Zero knock and we are only running a 16g that doesnt flow crap, so I was wondering if timing would give us more power.

The car is at an 11.1 afr and has only seen that afr when we where tuning, maybe a little richer but that is safe. We wont tune e85 an leaner than that. The guy that helped us tune is not a pro I guess since he dont have a dyno. But he has tuned mutlible 600whp cars and has tuned all EMS from SAFC, dsmlink, all the way to AEM. He has been tuning these cars for over 10 years.

We may not get MBT but we are staying safe and making good power. Have you tuned with e85, the stuff is amazing. The fuel enters at a much cooler rate. My brothers car is seeing lower temps just from switching to e85. It even takes a lot longer for the car to even warm up, its almost as if it wont reach full temp on real cold days. Ive seen knock on 16g c16 tunes, but with my brothers car we cant even get the thing to detonate no madder what we through at it.

 

[biglady112]

With small turbo you can get away with timing like that. On a big turbo like Jeff is running it would not even be a quaestion. Just remember that. You have to make up for the minimal amount of air going into the motor.

But, YOU CAN make E85 detonate. And it will happen very fast and severly damage things. I should know. I had a perfect tune with my mirage. Put the slicks on and shattered the piston on the third pass. Just because the knock sensor is not registering anything, does not mean bad things are going on in there. Don't get greedy. That extra .1-.3 seconds is not worth an engine.

Steven

 

[Locke]

Also what about the tq, doesnt the timing effect tq more than hp.

TQ and HP are relative to each other, since HP is a function of torque. (HP=(TQ x RPM)/5252)

 

[JayRolla]

With small turbo you can get away with timing like that. On a big turbo like Jeff is running it would not even be a quaestion. Just remember that. You have to make up for the minimal amount of air going into the motor.

But, YOU CAN make E85 detonate. And it will happen very fast and severly damage things. I should know. I had a perfect tune with my mirage. Put the slicks on and shattered the piston on the third pass. Just because the knock sensor is not registering anything, does not mean bad things are going on in there. Don't get greedy. That extra .1-.3 seconds is not worth an engine.

Steven

That is so true. I know that exhaust temps can get too high without seeing knock. I thought maybe we could put a little more timing in since thats pretty much what a 1g runs stock. But it was designed to run that timing with the lower boost. We will keep it around 22* seems to like it there.

 

[Brianawd]

I don't believe E85 makes can make more power then C16, c16 resists detonation more then E85 due to its higher octane level, so i don't see how people can run more spark advance with E85 than C16, it dosen't fit theory, maybe there just all too cocky, much like yourself.

It all depends on your turbo set up. In some setups you can make more power on e85 than you can on c16. The same is true for the reverse. Take my setup. fp3052 with all supporting mods. I could run 32psi all day with timing in the 20-21deg range and the car would never knock. So for me there was no reason to use c16. My feeling on the whole thing is any thing bigger that a gt37r (t04z) you are going to want to run c16. But then again there are people running bigger turbos than a t04z on e85 and are loving it.

 

[JeffGST]

I thought maybe we could put a little more timing in since thats pretty much what a 1g runs stock. But it was designed to run that timing with the lower boost. We will keep it around 22* seems to like it there.

Remember that not only was that stock 1G 22 degree designed for lower boost, but also a 7.8 to 1 compression motor. 22 degrees is plenty if not too much already.

I could run 32psi all day with timing in the 20-21deg range and the car would never knock. So for me there was no reason to use c16. My feeling on the whole thing is any thing bigger that a gt37r (t04z) you are going to want to run c16. But then again there are people running bigger turbos than a t04z on e85 and are loving it.

Just like Matt's Talon. I tuned it with E85 and a GT4202 and it made over 700+ WHP, but we just ran out of fuel. 1600's were at well over 100% and we could not raise fuel pressure any higher unless we added a 3rd fuel pump. By the way, we kept timing at 17 degrees. E85 is magic at the pump.

 

[slowgsr]

I must agree that E85 available at the pump is much more practical then running c16, however E85 isn't offered here at the pump, neither is c16. So until they are, my only practical options are 94 with meth injection, which is what i am using.

 

[Black_Bullet]

Interesting thread, you guys are misunderstanding each other a bit between a few posts but keep the good information coming... I need to soak all this in because the second i see e85 at any pump local to me the pump gas it getting burned out and the e85 will be taking its place and my timing and boost will go up while i drive off with a grin !!!

And jayrolla, this may not help in any way since timing needs are way different from car to car
but my car on race gas had most power at 25-26 degs by redline ( evo3, and stock compression)
Anything more than that i think is past MBT in most cases...
I think you and your brothers cars need to both see a dyno like the other guy suggested,
you already know the boost you want to run, so even 4 or 5 pulls on a dyno just playing with timing and AFR
could give you the info you need to know were the car makes the best numbers.